Google Git
Sign in
aomedia / libavif / 63f10971186e3dd270b90676da46211367dc8498 / . / src / read.c
blob: 989622e75eae145abae78947c8c662a16667b3be [file] [log] [blame]
// Copyright 2019 Joe Drago. All rights reserved.
// SPDX-License-Identifier: BSD-2-Clause
#include "avif/internal.h"
#include <assert.h>
#include <ctype.h>
#include <inttypes.h>
#include <limits.h>
#include <math.h>
#include <stdio.h>
#include <string.h>
#define AUXTYPE_SIZE 64
#define CONTENTTYPE_SIZE 64
// class VisualSampleEntry(codingname) extends SampleEntry(codingname) {
// unsigned int(16) pre_defined = 0;
// const unsigned int(16) reserved = 0;
// unsigned int(32)[3] pre_defined = 0;
// unsigned int(16) width;
// unsigned int(16) height;
// template unsigned int(32) horizresolution = 0x00480000; // 72 dpi
// template unsigned int(32) vertresolution = 0x00480000; // 72 dpi
// const unsigned int(32) reserved = 0;
// template unsigned int(16) frame_count = 1;
// string[32] compressorname;
// template unsigned int(16) depth = 0x0018;
// int(16) pre_defined = -1;
// // other boxes from derived specifications
// CleanApertureBox clap; // optional
// PixelAspectRatioBox pasp; // optional
// }
static const size_t VISUALSAMPLEENTRY_SIZE = 78;
// The only supported ipma box values for both version and flags are [0,1], so there technically
// can't be more than 4 unique tuples right now.
#define MAX_IPMA_VERSION_AND_FLAGS_SEEN 4
// ---------------------------------------------------------------------------
// AVIF codec type (AV1 or AV2)
static avifCodecType avifGetCodecType(const uint8_t * fourcc)
{
if (!memcmp(fourcc, "av01", 4)) {
return AVIF_CODEC_TYPE_AV1;
}
#if defined(AVIF_CODEC_AVM)
if (!memcmp(fourcc, "av02", 4)) {
return AVIF_CODEC_TYPE_AV2;
}
#endif
return AVIF_CODEC_TYPE_UNKNOWN;
}
static const char * avifGetConfigurationPropertyName(avifCodecType codecType)
{
switch (codecType) {
case AVIF_CODEC_TYPE_AV1:
return "av1C";
#if defined(AVIF_CODEC_AVM)
case AVIF_CODEC_TYPE_AV2:
return "av2C";
#endif
default:
assert(AVIF_FALSE);
return NULL;
}
}
// ---------------------------------------------------------------------------
// Box data structures
// ftyp
typedef struct avifFileType
{
uint8_t majorBrand[4];
uint32_t minorVersion;
// If not null, points to a memory block of 4 * compatibleBrandsCount bytes.
const uint8_t * compatibleBrands;
int compatibleBrandsCount;
} avifFileType;
// ispe
typedef struct avifImageSpatialExtents
{
uint32_t width;
uint32_t height;
} avifImageSpatialExtents;
// auxC
typedef struct avifAuxiliaryType
{
char auxType[AUXTYPE_SIZE];
} avifAuxiliaryType;
// infe mime content_type
typedef struct avifContentType
{
char contentType[CONTENTTYPE_SIZE];
} avifContentType;
// colr
typedef struct avifColourInformationBox
{
avifBool hasICC;
uint64_t iccOffset;
size_t iccSize;
avifBool hasNCLX;
avifColorPrimaries colorPrimaries;
avifTransferCharacteristics transferCharacteristics;
avifMatrixCoefficients matrixCoefficients;
avifRange range;
} avifColourInformationBox;
#define MAX_PIXI_PLANE_DEPTHS 4
typedef struct avifPixelInformationProperty
{
uint8_t planeDepths[MAX_PIXI_PLANE_DEPTHS];
uint8_t planeCount;
} avifPixelInformationProperty;
typedef struct avifOperatingPointSelectorProperty
{
uint8_t opIndex;
} avifOperatingPointSelectorProperty;
typedef struct avifLayerSelectorProperty
{
uint16_t layerID;
} avifLayerSelectorProperty;
typedef struct avifAV1LayeredImageIndexingProperty
{
uint32_t layerSize[3];
} avifAV1LayeredImageIndexingProperty;
// ---------------------------------------------------------------------------
// Top-level structures
struct avifMeta;
// Temporary storage for ipco/stsd contents until they can be associated and memcpy'd to an avifDecoderItem
typedef struct avifProperty
{
uint8_t type[4];
union
{
avifImageSpatialExtents ispe;
avifAuxiliaryType auxC;
avifColourInformationBox colr;
avifCodecConfigurationBox av1C; // TODO(yguyon): Rename or add av2C
avifPixelAspectRatioBox pasp;
avifCleanApertureBox clap;
avifImageRotation irot;
avifImageMirror imir;
avifPixelInformationProperty pixi;
avifOperatingPointSelectorProperty a1op;
avifLayerSelectorProperty lsel;
avifAV1LayeredImageIndexingProperty a1lx;
avifContentLightLevelInformationBox clli;
} u;
} avifProperty;
AVIF_ARRAY_DECLARE(avifPropertyArray, avifProperty, prop);
// Finds the first property of a given type.
static const avifProperty * avifPropertyArrayFind(const avifPropertyArray * properties, const char * type)
{
for (uint32_t propertyIndex = 0; propertyIndex < properties->count; ++propertyIndex) {
const avifProperty * prop = &properties->prop[propertyIndex];
if (!memcmp(prop->type, type, 4)) {
return prop;
}
}
return NULL;
}
AVIF_ARRAY_DECLARE(avifExtentArray, avifExtent, extent);
// one "item" worth for decoding (all iref, iloc, iprp, etc refer to one of these)
typedef struct avifDecoderItem
{
uint32_t id;
struct avifMeta * meta; // Unowned; A back-pointer for convenience
uint8_t type[4];
size_t size;
avifBool idatStored; // If true, offset is relative to the associated meta box's idat box (iloc construction_method==1)
uint32_t width; // Set from this item's ispe property, if present
uint32_t height; // Set from this item's ispe property, if present
avifContentType contentType;
avifPropertyArray properties;
avifExtentArray extents; // All extent offsets/sizes
avifRWData mergedExtents; // if set, is a single contiguous block of this item's extents (unused when extents.count == 1)
avifBool ownsMergedExtents; // if true, mergedExtents must be freed when this item is destroyed
avifBool partialMergedExtents; // If true, mergedExtents doesn't have all of the item data yet
uint32_t thumbnailForID; // if non-zero, this item is a thumbnail for Item #{thumbnailForID}
uint32_t auxForID; // if non-zero, this item is an auxC plane for Item #{auxForID}
uint32_t descForID; // if non-zero, this item is a content description for Item #{descForID}
uint32_t dimgForID; // if non-zero, this item is an input of derived Item #{dimgForID}
// If dimgForId is non-zero, this is the zero-based index of this item in the list of Item #{dimgForID}'s dimg
// Note that if the same item appears multiple times in the dimg box, this is the last index for this item.
uint32_t dimgIdx;
avifBool hasDimgFrom; // whether there is a 'dimg' box with this item's id as 'fromID'
uint32_t premByID; // if non-zero, this item is premultiplied by Item #{premByID}
avifBool hasUnsupportedEssentialProperty; // If true, this item cites a property flagged as 'essential' that libavif doesn't support (yet). Ignore the item, if so.
avifBool ipmaSeen; // if true, this item already received a property association
avifBool progressive; // if true, this item has progressive layers (a1lx), but does not select a specific layer (the layer_id value in lsel is set to 0xFFFF)
#if defined(AVIF_ENABLE_EXPERIMENTAL_METAV1)
avifPixelFormat metaV1PixelFormat; // Set from the MetaBox with version 1, if present (AVIF_PIXEL_FORMAT_NONE otherwise)
avifChromaSamplePosition metaV1ChromaSamplePosition; // Set from the MetaBox with version 1, if present (AVIF_CHROMA_SAMPLE_POSITION_UNKNOWN otherwise)
#endif
} avifDecoderItem;
AVIF_ARRAY_DECLARE(avifDecoderItemArray, avifDecoderItem *, item);
// grid storage
typedef struct avifImageGrid
{
uint32_t rows; // Legal range: [1-256]
uint32_t columns; // Legal range: [1-256]
uint32_t outputWidth;
uint32_t outputHeight;
} avifImageGrid;
// ---------------------------------------------------------------------------
// avifTrack
typedef struct avifSampleTableChunk
{
uint64_t offset;
} avifSampleTableChunk;
AVIF_ARRAY_DECLARE(avifSampleTableChunkArray, avifSampleTableChunk, chunk);
typedef struct avifSampleTableSampleToChunk
{
uint32_t firstChunk;
uint32_t samplesPerChunk;
uint32_t sampleDescriptionIndex;
} avifSampleTableSampleToChunk;
AVIF_ARRAY_DECLARE(avifSampleTableSampleToChunkArray, avifSampleTableSampleToChunk, sampleToChunk);
typedef struct avifSampleTableSampleSize
{
uint32_t size;
} avifSampleTableSampleSize;
AVIF_ARRAY_DECLARE(avifSampleTableSampleSizeArray, avifSampleTableSampleSize, sampleSize);
typedef struct avifSampleTableTimeToSample
{
uint32_t sampleCount;
uint32_t sampleDelta;
} avifSampleTableTimeToSample;
AVIF_ARRAY_DECLARE(avifSampleTableTimeToSampleArray, avifSampleTableTimeToSample, timeToSample);
typedef struct avifSyncSample
{
uint32_t sampleNumber;
} avifSyncSample;
AVIF_ARRAY_DECLARE(avifSyncSampleArray, avifSyncSample, syncSample);
typedef struct avifSampleDescription
{
uint8_t format[4];
avifPropertyArray properties;
} avifSampleDescription;
AVIF_ARRAY_DECLARE(avifSampleDescriptionArray, avifSampleDescription, description);
typedef struct avifSampleTable
{
avifSampleTableChunkArray chunks;
avifSampleDescriptionArray sampleDescriptions;
avifSampleTableSampleToChunkArray sampleToChunks;
avifSampleTableSampleSizeArray sampleSizes;
avifSampleTableTimeToSampleArray timeToSamples;
avifSyncSampleArray syncSamples;
uint32_t allSamplesSize; // If this is non-zero, sampleSizes will be empty and all samples will be this size
} avifSampleTable;
static void avifSampleTableDestroy(avifSampleTable * sampleTable);
static avifSampleTable * avifSampleTableCreate()
{
avifSampleTable * sampleTable = (avifSampleTable *)avifAlloc(sizeof(avifSampleTable));
if (sampleTable == NULL) {
return NULL;
}
memset(sampleTable, 0, sizeof(avifSampleTable));
if (!avifArrayCreate(&sampleTable->chunks, sizeof(avifSampleTableChunk), 16) ||
!avifArrayCreate(&sampleTable->sampleDescriptions, sizeof(avifSampleDescription), 2) ||
!avifArrayCreate(&sampleTable->sampleToChunks, sizeof(avifSampleTableSampleToChunk), 16) ||
!avifArrayCreate(&sampleTable->sampleSizes, sizeof(avifSampleTableSampleSize), 16) ||
!avifArrayCreate(&sampleTable->timeToSamples, sizeof(avifSampleTableTimeToSample), 16) ||
!avifArrayCreate(&sampleTable->syncSamples, sizeof(avifSyncSample), 16)) {
avifSampleTableDestroy(sampleTable);
return NULL;
}
return sampleTable;
}
static void avifSampleTableDestroy(avifSampleTable * sampleTable)
{
avifArrayDestroy(&sampleTable->chunks);
for (uint32_t i = 0; i < sampleTable->sampleDescriptions.count; ++i) {
avifSampleDescription * description = &sampleTable->sampleDescriptions.description[i];
avifArrayDestroy(&description->properties);
}
avifArrayDestroy(&sampleTable->sampleDescriptions);
avifArrayDestroy(&sampleTable->sampleToChunks);
avifArrayDestroy(&sampleTable->sampleSizes);
avifArrayDestroy(&sampleTable->timeToSamples);
avifArrayDestroy(&sampleTable->syncSamples);
avifFree(sampleTable);
}
static uint32_t avifSampleTableGetImageDelta(const avifSampleTable * sampleTable, int imageIndex)
{
int maxSampleIndex = 0;
for (uint32_t i = 0; i < sampleTable->timeToSamples.count; ++i) {
const avifSampleTableTimeToSample * timeToSample = &sampleTable->timeToSamples.timeToSample[i];
maxSampleIndex += timeToSample->sampleCount;
if ((imageIndex < maxSampleIndex) || (i == (sampleTable->timeToSamples.count - 1))) {
return timeToSample->sampleDelta;
}
}
// TODO: fail here?
return 1;
}
static avifCodecType avifSampleTableGetCodecType(const avifSampleTable * sampleTable)
{
for (uint32_t i = 0; i < sampleTable->sampleDescriptions.count; ++i) {
const avifCodecType codecType = avifGetCodecType(sampleTable->sampleDescriptions.description[i].format);
if (codecType != AVIF_CODEC_TYPE_UNKNOWN) {
return codecType;
}
}
return AVIF_CODEC_TYPE_UNKNOWN;
}
static uint32_t avifCodecConfigurationBoxGetDepth(const avifCodecConfigurationBox * av1C)
{
if (av1C->twelveBit) {
return 12;
} else if (av1C->highBitdepth) {
return 10;
}
return 8;
}
// This is used as a hint to validating the clap box in avifDecoderItemValidateProperties.
static avifPixelFormat avifCodecConfigurationBoxGetFormat(const avifCodecConfigurationBox * av1C)
{
if (av1C->monochrome) {
return AVIF_PIXEL_FORMAT_YUV400;
} else if (av1C->chromaSubsamplingY == 1) {
return AVIF_PIXEL_FORMAT_YUV420;
} else if (av1C->chromaSubsamplingX == 1) {
return AVIF_PIXEL_FORMAT_YUV422;
}
return AVIF_PIXEL_FORMAT_YUV444;
}
static const avifPropertyArray * avifSampleTableGetProperties(const avifSampleTable * sampleTable, avifCodecType codecType)
{
for (uint32_t i = 0; i < sampleTable->sampleDescriptions.count; ++i) {
const avifSampleDescription * description = &sampleTable->sampleDescriptions.description[i];
if (avifGetCodecType(description->format) == codecType) {
return &description->properties;
}
}
return NULL;
}
// one video track ("trak" contents)
typedef struct avifTrack
{
uint32_t id;
uint32_t auxForID; // if non-zero, this track is an auxC plane for Track #{auxForID}
uint32_t premByID; // if non-zero, this track is premultiplied by Track #{premByID}
uint32_t mediaTimescale;
uint64_t mediaDuration;
uint64_t trackDuration;
uint64_t segmentDuration;
avifBool isRepeating;
int repetitionCount;
uint32_t width;
uint32_t height;
avifSampleTable * sampleTable;
struct avifMeta * meta;
} avifTrack;
AVIF_ARRAY_DECLARE(avifTrackArray, avifTrack, track);
// ---------------------------------------------------------------------------
// avifCodecDecodeInput
avifCodecDecodeInput * avifCodecDecodeInputCreate(void)
{
avifCodecDecodeInput * decodeInput = (avifCodecDecodeInput *)avifAlloc(sizeof(avifCodecDecodeInput));
if (decodeInput == NULL) {
return NULL;
}
memset(decodeInput, 0, sizeof(avifCodecDecodeInput));
if (!avifArrayCreate(&decodeInput->samples, sizeof(avifDecodeSample), 1)) {
avifFree(decodeInput);
return NULL;
}
return decodeInput;
}
void avifCodecDecodeInputDestroy(avifCodecDecodeInput * decodeInput)
{
for (uint32_t sampleIndex = 0; sampleIndex < decodeInput->samples.count; ++sampleIndex) {
avifDecodeSample * sample = &decodeInput->samples.sample[sampleIndex];
if (sample->ownsData) {
avifRWDataFree((avifRWData *)&sample->data);
}
}
avifArrayDestroy(&decodeInput->samples);
avifFree(decodeInput);
}
// Returns how many samples are in the chunk.
static uint32_t avifGetSampleCountOfChunk(const avifSampleTableSampleToChunkArray * sampleToChunks, uint32_t chunkIndex)
{
uint32_t sampleCount = 0;
for (int sampleToChunkIndex = sampleToChunks->count - 1; sampleToChunkIndex >= 0; --sampleToChunkIndex) {
const avifSampleTableSampleToChunk * sampleToChunk = &sampleToChunks->sampleToChunk[sampleToChunkIndex];
if (sampleToChunk->firstChunk <= (chunkIndex + 1)) {
sampleCount = sampleToChunk->samplesPerChunk;
break;
}
}
return sampleCount;
}
static avifResult avifCodecDecodeInputFillFromSampleTable(avifCodecDecodeInput * decodeInput,
avifSampleTable * sampleTable,
const uint32_t imageCountLimit,
const uint64_t sizeHint,
avifDiagnostics * diag)
{
if (imageCountLimit) {
// Verify that the we're not about to exceed the frame count limit.
uint32_t imageCountLeft = imageCountLimit;
for (uint32_t chunkIndex = 0; chunkIndex < sampleTable->chunks.count; ++chunkIndex) {
// First, figure out how many samples are in this chunk
uint32_t sampleCount = avifGetSampleCountOfChunk(&sampleTable->sampleToChunks, chunkIndex);
if (sampleCount == 0) {
// chunks with 0 samples are invalid
avifDiagnosticsPrintf(diag, "Sample table contains a chunk with 0 samples");
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
if (sampleCount > imageCountLeft) {
// This file exceeds the imageCountLimit, bail out
avifDiagnosticsPrintf(diag, "Exceeded avifDecoder's imageCountLimit");
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
imageCountLeft -= sampleCount;
}
}
uint32_t sampleSizeIndex = 0;
for (uint32_t chunkIndex = 0; chunkIndex < sampleTable->chunks.count; ++chunkIndex) {
avifSampleTableChunk * chunk = &sampleTable->chunks.chunk[chunkIndex];
// First, figure out how many samples are in this chunk
uint32_t sampleCount = avifGetSampleCountOfChunk(&sampleTable->sampleToChunks, chunkIndex);
if (sampleCount == 0) {
// chunks with 0 samples are invalid
avifDiagnosticsPrintf(diag, "Sample table contains a chunk with 0 samples");
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
uint64_t sampleOffset = chunk->offset;
for (uint32_t sampleIndex = 0; sampleIndex < sampleCount; ++sampleIndex) {
uint32_t sampleSize = sampleTable->allSamplesSize;
if (sampleSize == 0) {
if (sampleSizeIndex >= sampleTable->sampleSizes.count) {
// We've run out of samples to sum
avifDiagnosticsPrintf(diag, "Truncated sample table");
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
avifSampleTableSampleSize * sampleSizePtr = &sampleTable->sampleSizes.sampleSize[sampleSizeIndex];
sampleSize = sampleSizePtr->size;
}
avifDecodeSample * sample = (avifDecodeSample *)avifArrayPush(&decodeInput->samples);
AVIF_CHECKERR(sample != NULL, AVIF_RESULT_OUT_OF_MEMORY);
sample->offset = sampleOffset;
sample->size = sampleSize;
sample->spatialID = AVIF_SPATIAL_ID_UNSET; // Not filtering by spatial_id
sample->sync = AVIF_FALSE; // to potentially be set to true following the outer loop
if (sampleSize > UINT64_MAX - sampleOffset) {
avifDiagnosticsPrintf(diag,
"Sample table contains an offset/size pair which overflows: [%" PRIu64 " / %u]",
sampleOffset,
sampleSize);
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
if (sizeHint && ((sampleOffset + sampleSize) > sizeHint)) {
avifDiagnosticsPrintf(diag, "Exceeded avifIO's sizeHint, possibly truncated data");
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
sampleOffset += sampleSize;
++sampleSizeIndex;
}
}
// Mark appropriate samples as sync
for (uint32_t syncSampleIndex = 0; syncSampleIndex < sampleTable->syncSamples.count; ++syncSampleIndex) {
uint32_t frameIndex = sampleTable->syncSamples.syncSample[syncSampleIndex].sampleNumber - 1; // sampleNumber is 1-based
if (frameIndex < decodeInput->samples.count) {
decodeInput->samples.sample[frameIndex].sync = AVIF_TRUE;
}
}
// Assume frame 0 is sync, just in case the stss box is absent in the BMFF. (Unnecessary?)
if (decodeInput->samples.count > 0) {
decodeInput->samples.sample[0].sync = AVIF_TRUE;
}
return AVIF_RESULT_OK;
}
static avifResult avifCodecDecodeInputFillFromDecoderItem(avifCodecDecodeInput * decodeInput,
avifDecoderItem * item,
avifBool allowProgressive,
const uint32_t imageCountLimit,
const uint64_t sizeHint,
avifDiagnostics * diag)
{
if (sizeHint && (item->size > sizeHint)) {
avifDiagnosticsPrintf(diag, "Exceeded avifIO's sizeHint, possibly truncated data");
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
uint8_t layerCount = 0;
size_t layerSizes[4] = { 0 };
const avifProperty * a1lxProp = avifPropertyArrayFind(&item->properties, "a1lx");
if (a1lxProp) {
// Calculate layer count and all layer sizes from the a1lx box, and then validate
size_t remainingSize = item->size;
for (int i = 0; i < 3; ++i) {
++layerCount;
const size_t layerSize = (size_t)a1lxProp->u.a1lx.layerSize[i];
if (layerSize) {
if (layerSize >= remainingSize) { // >= instead of > because there must be room for the last layer
avifDiagnosticsPrintf(diag, "a1lx layer index [%d] does not fit in item size", i);
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
layerSizes[i] = layerSize;
remainingSize -= layerSize;
} else {
layerSizes[i] = remainingSize;
remainingSize = 0;
break;
}
}
if (remainingSize > 0) {
AVIF_ASSERT_OR_RETURN(layerCount == 3);
++layerCount;
layerSizes[3] = remainingSize;
}
}
const avifProperty * lselProp = avifPropertyArrayFind(&item->properties, "lsel");
// Progressive images offer layers via the a1lxProp, but don't specify a layer selection with lsel.
//
// For backward compatibility with earlier drafts of AVIF spec v1.1.0, treat an absent lsel as
// equivalent to layer_id == 0xFFFF during the transitional period. Remove !lselProp when the test
// images have been updated to the v1.1.0 spec.
item->progressive = (a1lxProp && (!lselProp || (lselProp->u.lsel.layerID == 0xFFFF)));
if (lselProp && (lselProp->u.lsel.layerID != 0xFFFF)) {
// Layer selection. This requires that the underlying AV1 codec decodes all layers,
// and then only returns the requested layer as a single frame. To the user of libavif,
// this appears to be a single frame.
decodeInput->allLayers = AVIF_TRUE;
size_t sampleSize = 0;
if (layerCount > 0) {
// Optimization: If we're selecting a layer that doesn't require the entire image's payload (hinted via the a1lx box)
if (lselProp->u.lsel.layerID >= layerCount) {
avifDiagnosticsPrintf(diag,
"lsel property requests layer index [%u] which isn't present in a1lx property ([%u] layers)",
lselProp->u.lsel.layerID,
layerCount);
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
for (uint8_t i = 0; i <= lselProp->u.lsel.layerID; ++i) {
sampleSize += layerSizes[i];
}
} else {
// This layer's payload subsection is unknown, just use the whole payload
sampleSize = item->size;
}
avifDecodeSample * sample = (avifDecodeSample *)avifArrayPush(&decodeInput->samples);
AVIF_CHECKERR(sample != NULL, AVIF_RESULT_OUT_OF_MEMORY);
sample->itemID = item->id;
sample->offset = 0;
sample->size = sampleSize;
AVIF_ASSERT_OR_RETURN(lselProp->u.lsel.layerID < AVIF_MAX_AV1_LAYER_COUNT);
sample->spatialID = (uint8_t)lselProp->u.lsel.layerID;
sample->sync = AVIF_TRUE;
} else if (allowProgressive && item->progressive) {
// Progressive image. Decode all layers and expose them all to the user.
if (imageCountLimit && (layerCount > imageCountLimit)) {
avifDiagnosticsPrintf(diag, "Exceeded avifDecoder's imageCountLimit (progressive)");
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
decodeInput->allLayers = AVIF_TRUE;
size_t offset = 0;
for (int i = 0; i < layerCount; ++i) {
avifDecodeSample * sample = (avifDecodeSample *)avifArrayPush(&decodeInput->samples);
AVIF_CHECKERR(sample != NULL, AVIF_RESULT_OUT_OF_MEMORY);
sample->itemID = item->id;
sample->offset = offset;
sample->size = layerSizes[i];
sample->spatialID = AVIF_SPATIAL_ID_UNSET;
sample->sync = (i == 0); // Assume all layers depend on the first layer
offset += layerSizes[i];
}
} else {
// Typical case: Use the entire item's payload for a single frame output
avifDecodeSample * sample = (avifDecodeSample *)avifArrayPush(&decodeInput->samples);
AVIF_CHECKERR(sample != NULL, AVIF_RESULT_OUT_OF_MEMORY);
sample->itemID = item->id;
sample->offset = 0;
sample->size = item->size;
sample->spatialID = AVIF_SPATIAL_ID_UNSET;
sample->sync = AVIF_TRUE;
}
return AVIF_RESULT_OK;
}
// ---------------------------------------------------------------------------
// Helper macros / functions
#define BEGIN_STREAM(VARNAME, PTR, SIZE, DIAG, CONTEXT) \
avifROStream VARNAME; \
avifROData VARNAME##_roData; \
VARNAME##_roData.data = PTR; \
VARNAME##_roData.size = SIZE; \
avifROStreamStart(&VARNAME, &VARNAME##_roData, DIAG, CONTEXT)
// Use this to keep track of whether or not a child box that must be unique (0 or 1 present) has
// been seen yet, when parsing a parent box. If the "seen" bit is already set for a given box when
// it is encountered during parse, an error is thrown. Which bit corresponds to which box is
// dictated entirely by the calling function.
static avifBool uniqueBoxSeen(uint32_t * uniqueBoxFlags, uint32_t whichFlag, const char * parentBoxType, const char * boxType, avifDiagnostics * diagnostics)
{
const uint32_t flag = 1 << whichFlag;
if (*uniqueBoxFlags & flag) {
// This box has already been seen. Error!
avifDiagnosticsPrintf(diagnostics, "Box[%s] contains a duplicate unique box of type '%s'", parentBoxType, boxType);
return AVIF_FALSE;
}
// Mark this box as seen.
*uniqueBoxFlags |= flag;
return AVIF_TRUE;
}
// ---------------------------------------------------------------------------
// avifDecoderData
typedef struct avifTile
{
avifCodecDecodeInput * input;
avifCodecType codecType;
// This may point to a codec that it owns or point to a shared codec that it does not own. In the shared case, this will
// point to one of the avifCodec instances in avifDecoderData.
struct avifCodec * codec;
avifImage * image;
uint32_t width; // Either avifTrack.width or avifDecoderItem.width
uint32_t height; // Either avifTrack.height or avifDecoderItem.height
uint8_t operatingPoint;
} avifTile;
AVIF_ARRAY_DECLARE(avifTileArray, avifTile, tile);
// This holds one "meta" box (from the BMFF and HEIF standards) worth of relevant-to-AVIF information.
// * If a meta box is parsed from the root level of the BMFF, it can contain the information about
// "items" which might be color planes, alpha planes, or EXIF or XMP metadata.
// * If a meta box is parsed from inside of a track ("trak") box, any metadata (EXIF/XMP) items inside
// of that box are implicitly associated with that track.
typedef struct avifMeta
{
// Items (from HEIF) are the generic storage for any data that does not require timed processing
// (single image color planes, alpha planes, EXIF, XMP, etc). Each item has a unique integer ID >1,
// and is defined by a series of child boxes in a meta box:
// * iloc - location: byte offset to item data, item size in bytes
// * iinf - information: type of item (color planes, alpha plane, EXIF, XMP)
// * ipco - properties: dimensions, aspect ratio, image transformations, references to other items
// * ipma - associations: Attaches an item in the properties list to a given item
//
// Items are lazily created in this array when any of the above boxes refer to one by a new (unseen) ID,
// and are then further modified/updated as new information for an item's ID is parsed.
avifDecoderItemArray items;
// Any ipco boxes explained above are populated into this array as a staging area, which are
// then duplicated into the appropriate items upon encountering an item property association
// (ipma) box.
avifPropertyArray properties;
// Filled with the contents of this meta box's "idat" box, which is raw data that an item can
// directly refer to in its item location box (iloc) instead of just giving an offset into the
// overall file. If all items' iloc boxes simply point at an offset/length in the file itself,
// this buffer will likely be empty.
avifRWData idat;
// Ever-incrementing ID for uniquely identifying which 'meta' box contains an idat (when
// multiple meta boxes exist as BMFF siblings). Each time avifParseMetaBox() is called on an
// avifMeta struct, this value is incremented. Any time an additional meta box is detected at
// the same "level" (root level, trak level, etc), this ID helps distinguish which meta box's
// "idat" is which, as items implicitly reference idat boxes that exist in the same meta
// box.
uint32_t idatID;
// Contents of a pitm box, which signal which of the items in this file is the main image. For
// AVIF, this should point at an image item containing color planes, and all other items
// are ignored unless they refer to this item in some way (alpha plane, EXIF/XMP metadata).
uint32_t primaryItemID;
#if defined(AVIF_ENABLE_EXPERIMENTAL_METAV1)
// If true, the fields above were extracted from a MetaBox with version 1.
avifBool fromMetaV1;
#endif
#if defined(AVIF_ENABLE_EXPERIMENTAL_SAMPLE_TRANSFORM)
// Parsed from Sample Transform metadata if present, otherwise empty.
avifSampleTransformExpression sampleTransformExpression;
// Bit depth extracted from the pixi property of the Sample Transform derived image item, if any.
uint32_t sampleTransformDepth;
#endif
} avifMeta;
static void avifMetaDestroy(avifMeta * meta);
static avifMeta * avifMetaCreate()
{
avifMeta * meta = (avifMeta *)avifAlloc(sizeof(avifMeta));
if (meta == NULL) {
return NULL;
}
memset(meta, 0, sizeof(avifMeta));
if (!avifArrayCreate(&meta->items, sizeof(avifDecoderItem *), 8) || !avifArrayCreate(&meta->properties, sizeof(avifProperty), 16)) {
avifMetaDestroy(meta);
return NULL;
}
return meta;
}
static void avifMetaDestroy(avifMeta * meta)
{
for (uint32_t i = 0; i < meta->items.count; ++i) {
avifDecoderItem * item = meta->items.item[i];
avifArrayDestroy(&item->properties);
avifArrayDestroy(&item->extents);
if (item->ownsMergedExtents) {
avifRWDataFree(&item->mergedExtents);
}
avifFree(item);
}
avifArrayDestroy(&meta->items);
avifArrayDestroy(&meta->properties);
avifRWDataFree(&meta->idat);
#if defined(AVIF_ENABLE_EXPERIMENTAL_SAMPLE_TRANSFORM)
avifArrayDestroy(&meta->sampleTransformExpression);
#endif
avifFree(meta);
}
static avifResult avifCheckItemID(const char * boxFourcc, uint32_t itemID, avifDiagnostics * diag)
{
if (itemID == 0) {
avifDiagnosticsPrintf(diag, "Box[%.4s] has an invalid item ID [%u]", boxFourcc, itemID);
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
return AVIF_RESULT_OK;
}
static avifResult avifMetaFindOrCreateItem(avifMeta * meta, uint32_t itemID, avifDecoderItem ** item)
{
*item = NULL;
AVIF_ASSERT_OR_RETURN(itemID != 0);
for (uint32_t i = 0; i < meta->items.count; ++i) {
if (meta->items.item[i]->id == itemID) {
*item = meta->items.item[i];
return AVIF_RESULT_OK;
}
}
avifDecoderItem ** itemPtr = (avifDecoderItem **)avifArrayPush(&meta->items);
AVIF_CHECKERR(itemPtr != NULL, AVIF_RESULT_OUT_OF_MEMORY);
*item = (avifDecoderItem *)avifAlloc(sizeof(avifDecoderItem));
if (*item == NULL) {
avifArrayPop(&meta->items);
return AVIF_RESULT_OUT_OF_MEMORY;
}
memset(*item, 0, sizeof(avifDecoderItem));
*itemPtr = *item;
if (!avifArrayCreate(&(*item)->properties, sizeof(avifProperty), 16)) {
avifFree(*item);
*item = NULL;
avifArrayPop(&meta->items);
return AVIF_RESULT_OUT_OF_MEMORY;
}
if (!avifArrayCreate(&(*item)->extents, sizeof(avifExtent), 1)) {
avifArrayDestroy(&(*item)->properties);
avifFree(*item);
*item = NULL;
avifArrayPop(&meta->items);
return AVIF_RESULT_OUT_OF_MEMORY;
}
(*item)->id = itemID;
(*item)->meta = meta;
return AVIF_RESULT_OK;
}
// A group of AVIF tiles in an image item, such as a single tile or a grid of multiple tiles.
typedef struct avifTileInfo
{
unsigned int tileCount;
unsigned int decodedTileCount;
unsigned int firstTileIndex; // Within avifDecoderData.tiles.
avifImageGrid grid;
} avifTileInfo;
typedef struct avifDecoderData
{
avifMeta * meta; // The root-level meta box
avifTrackArray tracks;
avifTileArray tiles;
avifTileInfo tileInfos[AVIF_ITEM_CATEGORY_COUNT];
avifDecoderSource source;
// When decoding AVIF images with grid, use a single decoder instance for all the tiles instead of creating a decoder instance
// for each tile. If that is the case, |codec| will be used by all the tiles.
//
// There are some edge cases where we will still need multiple decoder instances:
// * For animated AVIF with alpha, we will need two instances (one for the color planes and one for the alpha plane since they are both
// encoded as separate video sequences). In this case, |codec| will be used for the color planes and |codecAlpha| will be
// used for the alpha plane.
// * For grid images with multiple layers. In this case, each tile will need its own decoder instance since there would be
// multiple layers in each tile. In this case, |codec| and |codecAlpha| are not used and each tile will have its own
// decoder instance.
// * For grid images where the operating points of all the tiles are not the same. In this case, each tile needs its own
// decoder instance (same as above).
avifCodec * codec;
avifCodec * codecAlpha;
uint8_t majorBrand[4]; // From the file's ftyp, used by AVIF_DECODER_SOURCE_AUTO
avifDiagnostics * diag; // Shallow copy; owned by avifDecoder
const avifSampleTable * sourceSampleTable; // NULL unless (source == AVIF_DECODER_SOURCE_TRACKS), owned by an avifTrack
avifBool cicpSet; // True if avifDecoder's image has had its CICP set correctly yet.
// This allows nclx colr boxes to override AV1 CICP, as specified in the MIAF
// standard (ISO/IEC 23000-22:2019), section 7.3.6.4:
// The colour information property takes precedence over any colour information
// in the image bitstream, i.e. if the property is present, colour information in
// the bitstream shall be ignored.
#if defined(AVIF_ENABLE_EXPERIMENTAL_SAMPLE_TRANSFORM)
// Remember the dimg association order to the Sample Transform derived image item.
// Colour items only. The alpha items are implicit.
uint8_t sampleTransformNumInputImageItems; // At most AVIF_SAMPLE_TRANSFORM_MAX_NUM_INPUT_IMAGE_ITEMS.
avifItemCategory sampleTransformInputImageItems[AVIF_SAMPLE_TRANSFORM_MAX_NUM_INPUT_IMAGE_ITEMS];
#endif
} avifDecoderData;
static void avifDecoderDataDestroy(avifDecoderData * data);
static avifDecoderData * avifDecoderDataCreate()
{
avifDecoderData * data = (avifDecoderData *)avifAlloc(sizeof(avifDecoderData));
if (data == NULL) {
return NULL;
}
memset(data, 0, sizeof(avifDecoderData));
data->meta = avifMetaCreate();
if (data->meta == NULL || !avifArrayCreate(&data->tracks, sizeof(avifTrack), 2) ||
!avifArrayCreate(&data->tiles, sizeof(avifTile), 8)) {
avifDecoderDataDestroy(data);
return NULL;
}
return data;
}
static void avifDecoderDataResetCodec(avifDecoderData * data)
{
for (unsigned int i = 0; i < data->tiles.count; ++i) {
avifTile * tile = &data->tiles.tile[i];
if (tile->image) {
avifImageFreePlanes(tile->image, AVIF_PLANES_ALL); // forget any pointers into codec image buffers
}
if (tile->codec) {
// Check if tile->codec was created separately and destroy it in that case.
if (tile->codec != data->codec && tile->codec != data->codecAlpha) {
avifCodecDestroy(tile->codec);
}
tile->codec = NULL;
}
}
for (int c = 0; c < AVIF_ITEM_CATEGORY_COUNT; ++c) {
data->tileInfos[c].decodedTileCount = 0;
}
if (data->codec) {
avifCodecDestroy(data->codec);
data->codec = NULL;
}
if (data->codecAlpha) {
avifCodecDestroy(data->codecAlpha);
data->codecAlpha = NULL;
}
}
static avifTile * avifDecoderDataCreateTile(avifDecoderData * data, avifCodecType codecType, uint32_t width, uint32_t height, uint8_t operatingPoint)
{
avifTile * tile = (avifTile *)avifArrayPush(&data->tiles);
if (tile == NULL) {
return NULL;
}
tile->codecType = codecType;
tile->image = avifImageCreateEmpty();
if (!tile->image) {
goto error;
}
tile->input = avifCodecDecodeInputCreate();
if (!tile->input) {
goto error;
}
tile->width = width;
tile->height = height;
tile->operatingPoint = operatingPoint;
return tile;
error:
if (tile->input) {
avifCodecDecodeInputDestroy(tile->input);
}
if (tile->image) {
avifImageDestroy(tile->image);
}
avifArrayPop(&data->tiles);
return NULL;
}
static avifTrack * avifDecoderDataCreateTrack(avifDecoderData * data)
{
avifTrack * track = (avifTrack *)avifArrayPush(&data->tracks);
if (track == NULL) {
return NULL;
}
track->meta = avifMetaCreate();
if (track->meta == NULL) {
avifArrayPop(&data->tracks);
return NULL;
}
return track;
}
static void avifDecoderDataClearTiles(avifDecoderData * data)
{
for (unsigned int i = 0; i < data->tiles.count; ++i) {
avifTile * tile = &data->tiles.tile[i];
if (tile->input) {
avifCodecDecodeInputDestroy(tile->input);
tile->input = NULL;
}
if (tile->codec) {
// Check if tile->codec was created separately and destroy it in that case.
if (tile->codec != data->codec && tile->codec != data->codecAlpha) {
avifCodecDestroy(tile->codec);
}
tile->codec = NULL;
}
if (tile->image) {
avifImageDestroy(tile->image);
tile->image = NULL;
}
}
data->tiles.count = 0;
for (int c = 0; c < AVIF_ITEM_CATEGORY_COUNT; ++c) {
data->tileInfos[c].tileCount = 0;
data->tileInfos[c].decodedTileCount = 0;
}
if (data->codec) {
avifCodecDestroy(data->codec);
data->codec = NULL;
}
if (data->codecAlpha) {
avifCodecDestroy(data->codecAlpha);
data->codecAlpha = NULL;
}
}
static void avifDecoderDataDestroy(avifDecoderData * data)
{
if (data->meta) {
avifMetaDestroy(data->meta);
}
for (uint32_t i = 0; i < data->tracks.count; ++i) {
avifTrack * track = &data->tracks.track[i];
if (track->sampleTable) {
avifSampleTableDestroy(track->sampleTable);
}
if (track->meta) {
avifMetaDestroy(track->meta);
}
}
avifArrayDestroy(&data->tracks);
avifDecoderDataClearTiles(data);
avifArrayDestroy(&data->tiles);
avifFree(data);
}
// This returns the max extent that has to be read in order to decode this item. If
// the item is stored in an idat, the data has already been read during Parse() and
// this function will return AVIF_RESULT_OK with a 0-byte extent.
static avifResult avifDecoderItemMaxExtent(const avifDecoderItem * item, const avifDecodeSample * sample, avifExtent * outExtent)
{
if (item->extents.count == 0) {
return AVIF_RESULT_TRUNCATED_DATA;
}
if (item->idatStored) {
// construction_method: idat(1)
if (item->meta->idat.size > 0) {
// Already read from a meta box during Parse()
memset(outExtent, 0, sizeof(avifExtent));
return AVIF_RESULT_OK;
}
// no associated idat box was found in the meta box, bail out
return AVIF_RESULT_NO_CONTENT;
}
// construction_method: file(0)
if (sample->size == 0) {
return AVIF_RESULT_TRUNCATED_DATA;
}
uint64_t remainingOffset = sample->offset;
size_t remainingBytes = sample->size; // This may be smaller than item->size if the item is progressive
// Assert that the for loop below will execute at least one iteration.
AVIF_ASSERT_OR_RETURN(item->extents.count != 0);
uint64_t minOffset = UINT64_MAX;
uint64_t maxOffset = 0;
for (uint32_t extentIter = 0; extentIter < item->extents.count; ++extentIter) {
avifExtent * extent = &item->extents.extent[extentIter];
// Make local copies of extent->offset and extent->size as they might need to be adjusted
// due to the sample's offset.
uint64_t startOffset = extent->offset;
size_t extentSize = extent->size;
if (remainingOffset) {
if (remainingOffset >= extentSize) {
remainingOffset -= extentSize;
continue;
} else {
if (remainingOffset > UINT64_MAX - startOffset) {
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
startOffset += remainingOffset;
extentSize -= (size_t)remainingOffset;
remainingOffset = 0;
}
}
const size_t usedExtentSize = (extentSize < remainingBytes) ? extentSize : remainingBytes;
if (usedExtentSize > UINT64_MAX - startOffset) {
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
const uint64_t endOffset = startOffset + usedExtentSize;
if (minOffset > startOffset) {
minOffset = startOffset;
}
if (maxOffset < endOffset) {
maxOffset = endOffset;
}
remainingBytes -= usedExtentSize;
if (remainingBytes == 0) {
// We've got enough bytes for this sample.
break;
}
}
if (remainingBytes != 0) {
return AVIF_RESULT_TRUNCATED_DATA;
}
outExtent->offset = minOffset;
const uint64_t extentLength = maxOffset - minOffset;
if (extentLength > SIZE_MAX) {
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
outExtent->size = (size_t)extentLength;
return AVIF_RESULT_OK;
}
static uint8_t avifDecoderItemOperatingPoint(const avifDecoderItem * item)
{
const avifProperty * a1opProp = avifPropertyArrayFind(&item->properties, "a1op");
if (a1opProp) {
return a1opProp->u.a1op.opIndex;
}
return 0; // default
}
static avifResult avifDecoderItemValidateProperties(const avifDecoderItem * item,
const char * configPropName,
avifDiagnostics * diag,
const avifStrictFlags strictFlags)
{
const avifProperty * const configProp = avifPropertyArrayFind(&item->properties, configPropName);
if (!configProp) {
// An item configuration property box is mandatory in all valid AVIF configurations. Bail out.
avifDiagnosticsPrintf(diag, "Item ID %u of type '%.4s' is missing mandatory %s property", item->id, (const char *)item->type, configPropName);
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
if (!memcmp(item->type, "grid", 4)) {
for (uint32_t i = 0; i < item->meta->items.count; ++i) {
avifDecoderItem * tile = item->meta->items.item[i];
if (tile->dimgForID != item->id) {
continue;
}
// Tile item types were checked in avifDecoderGenerateImageTiles(), no need to do it here.
// MIAF (ISO 23000-22:2019), Section 7.3.11.4.1:
// All input images of a grid image item shall use the same [...] chroma sampling format,
// and the same decoder configuration (see 7.3.6.2).
// The chroma sampling format is part of the decoder configuration.
const avifProperty * tileConfigProp = avifPropertyArrayFind(&tile->properties, configPropName);
if (!tileConfigProp) {
avifDiagnosticsPrintf(diag,
"Tile item ID %u of type '%.4s' is missing mandatory %s property",
tile->id,
(const char *)tile->type,
configPropName);
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
// configProp was copied from a tile item to the grid item. Comparing tileConfigProp with it
// is equivalent to comparing tileConfigProp with the configPropName from the first tile.
if ((tileConfigProp->u.av1C.seqProfile != configProp->u.av1C.seqProfile) ||
(tileConfigProp->u.av1C.seqLevelIdx0 != configProp->u.av1C.seqLevelIdx0) ||
(tileConfigProp->u.av1C.seqTier0 != configProp->u.av1C.seqTier0) ||
(tileConfigProp->u.av1C.highBitdepth != configProp->u.av1C.highBitdepth) ||
(tileConfigProp->u.av1C.twelveBit != configProp->u.av1C.twelveBit) ||
(tileConfigProp->u.av1C.monochrome != configProp->u.av1C.monochrome) ||
(tileConfigProp->u.av1C.chromaSubsamplingX != configProp->u.av1C.chromaSubsamplingX) ||
(tileConfigProp->u.av1C.chromaSubsamplingY != configProp->u.av1C.chromaSubsamplingY) ||
(tileConfigProp->u.av1C.chromaSamplePosition != configProp->u.av1C.chromaSamplePosition)) {
avifDiagnosticsPrintf(diag,
"The fields of the %s property of tile item ID %u of type '%.4s' differs from other tiles",
configPropName,
tile->id,
(const char *)tile->type);
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
}
}
const avifProperty * pixiProp = avifPropertyArrayFind(&item->properties, "pixi");
if (!pixiProp && (strictFlags & AVIF_STRICT_PIXI_REQUIRED)) {
// A pixi box is mandatory in all valid AVIF configurations. Bail out.
avifDiagnosticsPrintf(diag,
"[Strict] Item ID %u of type '%.4s' is missing mandatory pixi property",
item->id,
(const char *)item->type);
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
if (pixiProp) {
const uint32_t configDepth = avifCodecConfigurationBoxGetDepth(&configProp->u.av1C);
for (uint8_t i = 0; i < pixiProp->u.pixi.planeCount; ++i) {
if (pixiProp->u.pixi.planeDepths[i] != configDepth) {
// pixi depth must match configuration property depth
avifDiagnosticsPrintf(diag,
"Item ID %u depth specified by pixi property [%u] does not match %s property depth [%u]",
item->id,
pixiProp->u.pixi.planeDepths[i],
configPropName,
configDepth);
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
}
}
#if defined(AVIF_ENABLE_EXPERIMENTAL_METAV1)
if (item->metaV1PixelFormat != AVIF_PIXEL_FORMAT_NONE) {
// This is a 'meta' box with version 1.
if (item->metaV1PixelFormat != avifCodecConfigurationBoxGetFormat(&configProp->u.av1C)) {
avifDiagnosticsPrintf(diag,
"Item ID %u format [%s] specified by meta box with version 1 does not match %s property format [%s]",
item->id,
avifPixelFormatToString(item->metaV1PixelFormat),
configPropName,
avifPixelFormatToString(avifCodecConfigurationBoxGetFormat(&configProp->u.av1C)));
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
if (configProp->u.av1C.chromaSamplePosition == /*CSP_UNKNOWN=*/0) {
// Section 6.4.2. Color config semantics of AV1 specification says:
// CSP_UNKNOWN - the source video transfer function must be signaled outside the AV1 bitstream
// See https://aomediacodec.github.io/av1-spec/#color-config-semantics
// So item->metaV1ChromaSamplePosition can differ and will override the AV1 value.
} else if ((uint8_t)item->metaV1ChromaSamplePosition != configProp->u.av1C.chromaSamplePosition) {
avifDiagnosticsPrintf(diag,
"Item ID %u chroma sample position [%u] specified by meta box with version 1 does not match %s property chroma sample position [%u]",
item->id,
(uint32_t)item->metaV1ChromaSamplePosition,
configPropName,
configProp->u.av1C.chromaSamplePosition);
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
}
#endif // AVIF_ENABLE_EXPERIMENTAL_METAV1
if (strictFlags & AVIF_STRICT_CLAP_VALID) {
const avifProperty * clapProp = avifPropertyArrayFind(&item->properties, "clap");
if (clapProp) {
const avifProperty * ispeProp = avifPropertyArrayFind(&item->properties, "ispe");
if (!ispeProp) {
avifDiagnosticsPrintf(diag,
"[Strict] Item ID %u is missing an ispe property, so its clap property cannot be validated",
item->id);
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
avifCropRect cropRect;
const uint32_t imageW = ispeProp->u.ispe.width;
const uint32_t imageH = ispeProp->u.ispe.height;
const avifPixelFormat configFormat = avifCodecConfigurationBoxGetFormat(&configProp->u.av1C);
avifBool validClap = avifCropRectConvertCleanApertureBox(&cropRect, &clapProp->u.clap, imageW, imageH, configFormat, diag);
if (!validClap) {
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
}
}
return AVIF_RESULT_OK;
}
static avifResult avifDecoderItemRead(avifDecoderItem * item,
avifIO * io,
avifROData * outData,
size_t offset,
size_t partialByteCount,
avifDiagnostics * diag)
{
if (item->mergedExtents.data && !item->partialMergedExtents) {
// Multiple extents have already been concatenated for this item, just return it
if (offset >= item->mergedExtents.size) {
avifDiagnosticsPrintf(diag, "Item ID %u read has overflowing offset", item->id);
return AVIF_RESULT_TRUNCATED_DATA;
}
outData->data = item->mergedExtents.data + offset;
outData->size = item->mergedExtents.size - offset;
return AVIF_RESULT_OK;
}
if (item->extents.count == 0) {
avifDiagnosticsPrintf(diag, "Item ID %u has zero extents", item->id);
return AVIF_RESULT_TRUNCATED_DATA;
}
// Find this item's source of all extents' data, based on the construction method
const avifRWData * idatBuffer = NULL;
if (item->idatStored) {
// construction_method: idat(1)
if (item->meta->idat.size > 0) {
idatBuffer = &item->meta->idat;
} else {
// no associated idat box was found in the meta box, bail out
avifDiagnosticsPrintf(diag, "Item ID %u is stored in an idat, but no associated idat box was found", item->id);
return AVIF_RESULT_NO_CONTENT;
}
}
// Merge extents into a single contiguous buffer
if ((io->sizeHint > 0) && (item->size > io->sizeHint)) {
// Sanity check: somehow the sum of extents exceeds the entire file or idat size!
avifDiagnosticsPrintf(diag, "Item ID %u reported size failed size hint sanity check. Truncated data?", item->id);
return AVIF_RESULT_TRUNCATED_DATA;
}
if (offset >= item->size) {
avifDiagnosticsPrintf(diag, "Item ID %u read has overflowing offset", item->id);
return AVIF_RESULT_TRUNCATED_DATA;
}
const size_t maxOutputSize = item->size - offset;
const size_t readOutputSize = (partialByteCount && (partialByteCount < maxOutputSize)) ? partialByteCount : maxOutputSize;
const size_t totalBytesToRead = offset + readOutputSize;
// If there is a single extent for this item and the source of the read buffer is going to be
// persistent for the lifetime of the avifDecoder (whether it comes from its own internal
// idatBuffer or from a known-persistent IO), we can avoid buffer duplication and just use the
// preexisting buffer.
avifBool singlePersistentBuffer = ((item->extents.count == 1) && (idatBuffer || io->persistent));
if (!singlePersistentBuffer) {
// Always allocate the item's full size here, as progressive image decodes will do partial
// reads into this buffer and begin feeding the buffer to the underlying AV1 decoder, but
// will then write more into this buffer without flushing the AV1 decoder (which is still
// holding the address of the previous allocation of this buffer). This strategy avoids
// use-after-free issues in the AV1 decoder and unnecessary reallocs as a typical
// progressive decode use case will eventually decode the final layer anyway.
AVIF_CHECKRES(avifRWDataRealloc(&item->mergedExtents, item->size));
item->ownsMergedExtents = AVIF_TRUE;
}
// Set this until we manage to fill the entire mergedExtents buffer
item->partialMergedExtents = AVIF_TRUE;
uint8_t * front = item->mergedExtents.data;
size_t remainingBytes = totalBytesToRead;
for (uint32_t extentIter = 0; extentIter < item->extents.count; ++extentIter) {
avifExtent * extent = &item->extents.extent[extentIter];
size_t bytesToRead = extent->size;
if (bytesToRead > remainingBytes) {
bytesToRead = remainingBytes;
}
avifROData offsetBuffer;
if (idatBuffer) {
if (extent->offset > idatBuffer->size) {
avifDiagnosticsPrintf(diag, "Item ID %u has impossible extent offset in idat buffer", item->id);
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
// Since extent->offset (a uint64_t) is not bigger than idatBuffer->size (a size_t),
// it is safe to cast extent->offset to size_t.
const size_t extentOffset = (size_t)extent->offset;
if (extent->size > idatBuffer->size - extentOffset) {
avifDiagnosticsPrintf(diag, "Item ID %u has impossible extent size in idat buffer", item->id);
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
offsetBuffer.data = idatBuffer->data + extentOffset;
offsetBuffer.size = idatBuffer->size - extentOffset;
} else {
// construction_method: file(0)
if ((io->sizeHint > 0) && (extent->offset > io->sizeHint)) {
avifDiagnosticsPrintf(diag, "Item ID %u extent offset failed size hint sanity check. Truncated data?", item->id);
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
avifResult readResult = io->read(io, 0, extent->offset, bytesToRead, &offsetBuffer);
if (readResult != AVIF_RESULT_OK) {
return readResult;
}
if (bytesToRead != offsetBuffer.size) {
avifDiagnosticsPrintf(diag,
"Item ID %u tried to read %zu bytes, but only received %zu bytes",
item->id,
bytesToRead,
offsetBuffer.size);
return AVIF_RESULT_TRUNCATED_DATA;
}
}
if (singlePersistentBuffer) {
memcpy(&item->mergedExtents, &offsetBuffer, sizeof(avifRWData));
item->mergedExtents.size = bytesToRead;
} else {
AVIF_ASSERT_OR_RETURN(item->ownsMergedExtents);
AVIF_ASSERT_OR_RETURN(front);
memcpy(front, offsetBuffer.data, bytesToRead);
front += bytesToRead;
}
remainingBytes -= bytesToRead;
if (remainingBytes == 0) {
// This happens when partialByteCount is set
break;
}
}
if (remainingBytes != 0) {
// This should be impossible?
avifDiagnosticsPrintf(diag, "Item ID %u has %zu unexpected trailing bytes", item->id, remainingBytes);
return AVIF_RESULT_TRUNCATED_DATA;
}
outData->data = item->mergedExtents.data + offset;
outData->size = readOutputSize;
item->partialMergedExtents = (item->size != totalBytesToRead);
return AVIF_RESULT_OK;
}
// Returns the avifCodecType of the first tile of the gridItem.
static avifCodecType avifDecoderItemGetGridCodecType(const avifDecoderItem * gridItem)
{
for (uint32_t i = 0; i < gridItem->meta->items.count; ++i) {
avifDecoderItem * item = gridItem->meta->items.item[i];
const avifCodecType tileCodecType = avifGetCodecType(item->type);
if ((item->dimgForID == gridItem->id) && (tileCodecType != AVIF_CODEC_TYPE_UNKNOWN)) {
return tileCodecType;
}
}
return AVIF_CODEC_TYPE_UNKNOWN;
}
static avifResult avifDecoderGenerateImageGridTiles(avifDecoder * decoder, avifImageGrid * grid, avifDecoderItem * gridItem, avifItemCategory itemCategory)
{
// Count number of dimg for this item, bail out if it doesn't match perfectly
unsigned int tilesAvailable = 0;
avifDecoderItem * firstTileItem = NULL;
avifBool progressive = AVIF_TRUE;
for (uint32_t i = 0; i < gridItem->meta->items.count; ++i) {
avifDecoderItem * item = gridItem->meta->items.item[i];
if (item->dimgForID != gridItem->id) {
continue;
}
// According to HEIF (ISO 14496-12), Section 6.6.2.3.1, the SingleItemTypeReferenceBox of type 'dimg'
// identifies the input images of the derived image item of type 'grid'. Since the reference_count
// shall be equal to rows*columns, unknown tile item types cannot be skipped but must be considered
// as errors.
const avifCodecType tileCodecType = avifGetCodecType(item->type);
if (tileCodecType == AVIF_CODEC_TYPE_UNKNOWN) {
char type[4];
for (int j = 0; j < 4; j++) {
if (isprint((unsigned char)item->type[j])) {
type[j] = item->type[j];
} else {
type[j] = '.';
}
}
avifDiagnosticsPrintf(&decoder->diag,
"Tile item ID %u has an unknown item type '%.4s' (%02x%02x%02x%02x)",
item->id,
type,
item->type[0],
item->type[1],
item->type[2],
item->type[3]);
return AVIF_RESULT_INVALID_IMAGE_GRID;
}
if (item->hasUnsupportedEssentialProperty) {
// An essential property isn't supported by libavif; can't
// decode a grid image if any tile in the grid isn't supported.
avifDiagnosticsPrintf(&decoder->diag, "Grid image contains tile with an unsupported property marked as essential");
return AVIF_RESULT_INVALID_IMAGE_GRID;
}
const avifTile * tile =
avifDecoderDataCreateTile(decoder->data, tileCodecType, item->width, item->height, avifDecoderItemOperatingPoint(item));
AVIF_CHECKERR(tile != NULL, AVIF_RESULT_OUT_OF_MEMORY);
AVIF_CHECKRES(avifCodecDecodeInputFillFromDecoderItem(tile->input,
item,
decoder->allowProgressive,
decoder->imageCountLimit,
decoder->io->sizeHint,
&decoder->diag));
tile->input->itemCategory = itemCategory;
if (firstTileItem == NULL) {
firstTileItem = item;
// Adopt the configuration property of the first image item tile, so that it can be queried from
// the top-level color/alpha item during avifDecoderReset().
const avifCodecType codecType = avifGetCodecType(item->type);
const char * configPropName = avifGetConfigurationPropertyName(codecType);
const avifProperty * srcProp = avifPropertyArrayFind(&item->properties, configPropName);
if (!srcProp) {
avifDiagnosticsPrintf(&decoder->diag, "Grid image's first tile is missing an %s property", configPropName);
return AVIF_RESULT_INVALID_IMAGE_GRID;
}
avifProperty * dstProp = (avifProperty *)avifArrayPush(&gridItem->properties);
AVIF_CHECKERR(dstProp != NULL, AVIF_RESULT_OUT_OF_MEMORY);
*dstProp = *srcProp;
} else if (memcmp(item->type, firstTileItem->type, 4)) {
// MIAF (ISO 23000-22:2019), Section 7.3.11.4.1:
// All input images of a grid image item shall use the same coding format [...]
// The coding format is defined by the item type.
avifDiagnosticsPrintf(&decoder->diag,
"Tile item ID %u of type '%.4s' differs from other tile type '%.4s'",
item->id,
(const char *)item->type,
(const char *)firstTileItem->type);
return AVIF_RESULT_INVALID_IMAGE_GRID;
}
if (!item->progressive) {
progressive = AVIF_FALSE;
}
++tilesAvailable;
}
if (itemCategory == AVIF_ITEM_COLOR && progressive) {
// If all the items that make up the grid are progressive, then propagate that status to the top-level grid item.
gridItem->progressive = AVIF_TRUE;
}
if (tilesAvailable != grid->rows * grid->columns) {
avifDiagnosticsPrintf(&decoder->diag,
"Grid image of dimensions %ux%u requires %u tiles, but %u were found",
grid->columns,
grid->rows,
grid->rows * grid->columns,
tilesAvailable);
return AVIF_RESULT_INVALID_IMAGE_GRID;
}
return AVIF_RESULT_OK;
}
// Allocates the dstImage. Also verifies some spec compliance rules for grids, if relevant.
static avifResult avifDecoderDataAllocateImagePlanes(avifDecoderData * data, const avifTileInfo * info, avifImage * dstImage)
{
const avifTile * tile = &data->tiles.tile[info->firstTileIndex];
uint32_t dstWidth;
uint32_t dstHeight;
if (info->grid.rows > 0 && info->grid.columns > 0) {
const avifImageGrid * grid = &info->grid;
// Validate grid image size and tile size.
//
// HEIF (ISO/IEC 23008-12:2017), Section 6.6.2.3.1:
// The tiled input images shall completely "cover" the reconstructed image grid canvas, ...
if (((tile->image->width * grid->columns) < grid->outputWidth) || ((tile->image->height * grid->rows) < grid->outputHeight)) {
avifDiagnosticsPrintf(data->diag,
"Grid image tiles do not completely cover the image (HEIF (ISO/IEC 23008-12:2017), Section 6.6.2.3.1)");
return AVIF_RESULT_INVALID_IMAGE_GRID;
}
// Tiles in the rightmost column and bottommost row must overlap the reconstructed image grid canvas. See MIAF (ISO/IEC 23000-22:2019), Section 7.3.11.4.2, Figure 2.
if (((tile->image->width * (grid->columns - 1)) >= grid->outputWidth) ||
((tile->image->height * (grid->rows - 1)) >= grid->outputHeight)) {
avifDiagnosticsPrintf(data->diag,
"Grid image tiles in the rightmost column and bottommost row do not overlap the reconstructed image grid canvas. See MIAF (ISO/IEC 23000-22:2019), Section 7.3.11.4.2, Figure 2");
return AVIF_RESULT_INVALID_IMAGE_GRID;
}
if (!avifAreGridDimensionsValid(tile->image->yuvFormat,
grid->outputWidth,
grid->outputHeight,
tile->image->width,
tile->image->height,
data->diag)) {
return AVIF_RESULT_INVALID_IMAGE_GRID;
}
dstWidth = grid->outputWidth;
dstHeight = grid->outputHeight;
} else {
// Only one tile. Width and height are inherited from the 'ispe' property of the corresponding avifDecoderItem.
dstWidth = tile->width;
dstHeight = tile->height;
}
const avifBool alpha = avifIsAlpha(tile->input->itemCategory);
if (alpha) {
// An alpha tile does not contain any YUV pixels.
AVIF_ASSERT_OR_RETURN(tile->image->yuvFormat == AVIF_PIXEL_FORMAT_NONE);
}
const uint32_t dstDepth = tile->image->depth;
// Lazily populate dstImage with the new frame's properties.
const avifBool dimsOrDepthIsDifferent = (dstImage->width != dstWidth) || (dstImage->height != dstHeight) ||
(dstImage->depth != dstDepth);
const avifBool yuvFormatIsDifferent = !alpha && (dstImage->yuvFormat != tile->image->yuvFormat);
if (dimsOrDepthIsDifferent || yuvFormatIsDifferent) {
if (alpha) {
// Alpha doesn't match size, just bail out
avifDiagnosticsPrintf(data->diag, "Alpha plane dimensions do not match color plane dimensions");
return AVIF_RESULT_INVALID_IMAGE_GRID;
}
if (dimsOrDepthIsDifferent) {
avifImageFreePlanes(dstImage, AVIF_PLANES_ALL);
dstImage->width = dstWidth;
dstImage->height = dstHeight;
dstImage->depth = dstDepth;
}
if (yuvFormatIsDifferent) {
avifImageFreePlanes(dstImage, AVIF_PLANES_YUV);
dstImage->yuvFormat = tile->image->yuvFormat;
}
// Keep dstImage->yuvRange which is already set to its correct value
// (extracted from the 'colr' box if parsed or from a Sequence Header OBU otherwise).
if (!data->cicpSet) {
data->cicpSet = AVIF_TRUE;
dstImage->colorPrimaries = tile->image->colorPrimaries;
dstImage->transferCharacteristics = tile->image->transferCharacteristics;
dstImage->matrixCoefficients = tile->image->matrixCoefficients;
}
}
if (avifImageAllocatePlanes(dstImage, alpha ? AVIF_PLANES_A : AVIF_PLANES_YUV) != AVIF_RESULT_OK) {
avifDiagnosticsPrintf(data->diag, "Image allocation failure");
return AVIF_RESULT_OUT_OF_MEMORY;
}
return AVIF_RESULT_OK;
}
// Copies over the pixels from the tile into dstImage.
// Verifies that the relevant properties of the tile match those of the first tile in case of a grid.
static avifResult avifDecoderDataCopyTileToImage(avifDecoderData * data,
const avifTileInfo * info,
avifImage * dstImage,
const avifTile * tile,
unsigned int tileIndex)
{
const avifTile * firstTile = &data->tiles.tile[info->firstTileIndex];
if (tile != firstTile) {
// Check for tile consistency. All tiles in a grid image should match the first tile in the properties checked below.
if ((tile->image->width != firstTile->image->width) || (tile->image->height != firstTile->image->height) ||
(tile->image->depth != firstTile->image->depth) || (tile->image->yuvFormat != firstTile->image->yuvFormat) ||
(tile->image->yuvRange != firstTile->image->yuvRange) || (tile->image->colorPrimaries != firstTile->image->colorPrimaries) ||
(tile->image->transferCharacteristics != firstTile->image->transferCharacteristics) ||
(tile->image->matrixCoefficients != firstTile->image->matrixCoefficients)) {
avifDiagnosticsPrintf(data->diag, "Grid image contains mismatched tiles");
return AVIF_RESULT_INVALID_IMAGE_GRID;
}
}
avifImage srcView;
avifImageSetDefaults(&srcView);
avifImage dstView;
avifImageSetDefaults(&dstView);
avifCropRect dstViewRect = { 0, 0, firstTile->image->width, firstTile->image->height };
if (info->grid.rows > 0 && info->grid.columns > 0) {
unsigned int rowIndex = tileIndex / info->grid.columns;
unsigned int colIndex = tileIndex % info->grid.columns;
dstViewRect.x = firstTile->image->width * colIndex;
dstViewRect.y = firstTile->image->height * rowIndex;
if (dstViewRect.x + dstViewRect.width > info->grid.outputWidth) {
dstViewRect.width = info->grid.outputWidth - dstViewRect.x;
}
if (dstViewRect.y + dstViewRect.height > info->grid.outputHeight) {
dstViewRect.height = info->grid.outputHeight - dstViewRect.y;
}
}
const avifCropRect srcViewRect = { 0, 0, dstViewRect.width, dstViewRect.height };
AVIF_ASSERT_OR_RETURN(avifImageSetViewRect(&dstView, dstImage, &dstViewRect) == AVIF_RESULT_OK &&
avifImageSetViewRect(&srcView, tile->image, &srcViewRect) == AVIF_RESULT_OK);
avifImageCopySamples(&dstView, &srcView, avifIsAlpha(tile->input->itemCategory) ? AVIF_PLANES_A : AVIF_PLANES_YUV);
return AVIF_RESULT_OK;
}
// If colorId == 0 (a sentinel value as item IDs must be nonzero), accept any found EXIF/XMP metadata. Passing in 0
// is used when finding metadata in a meta box embedded in a trak box, as any items inside of a meta box that is
// inside of a trak box are implicitly associated to the track.
static avifResult avifDecoderFindMetadata(avifDecoder * decoder, avifMeta * meta, avifImage * image, uint32_t colorId)
{
if (decoder->ignoreExif && decoder->ignoreXMP) {
// Nothing to do!
return AVIF_RESULT_OK;
}
for (uint32_t itemIndex = 0; itemIndex < meta->items.count; ++itemIndex) {
avifDecoderItem * item = meta->items.item[itemIndex];
if (!item->size) {
continue;
}
if (item->hasUnsupportedEssentialProperty) {
// An essential property isn't supported by libavif; ignore the item.
continue;
}
if ((colorId > 0) && (item->descForID != colorId)) {
// Not a content description (metadata) for the colorOBU, skip it
continue;
}
if (!decoder->ignoreExif && !memcmp(item->type, "Exif", 4)) {
avifROData exifContents;
avifResult readResult = avifDecoderItemRead(item, decoder->io, &exifContents, 0, 0, &decoder->diag);
if (readResult != AVIF_RESULT_OK) {
return readResult;
}
// Advance past Annex A.2.1's header
BEGIN_STREAM(exifBoxStream, exifContents.data, exifContents.size, &decoder->diag, "Exif header");
#if defined(AVIF_ENABLE_EXPERIMENTAL_METAV1)
// The MetaBox with version 1 does not signal the exifTiffHeaderOffset.
if (!meta->fromMetaV1)
#endif
{
uint32_t exifTiffHeaderOffset;
AVIF_CHECKERR(avifROStreamReadU32(&exifBoxStream, &exifTiffHeaderOffset),
AVIF_RESULT_INVALID_EXIF_PAYLOAD); // unsigned int(32) exif_tiff_header_offset;
size_t expectedExifTiffHeaderOffset;
AVIF_CHECKRES(avifGetExifTiffHeaderOffset(avifROStreamCurrent(&exifBoxStream),
avifROStreamRemainingBytes(&exifBoxStream),
&expectedExifTiffHeaderOffset));
AVIF_CHECKERR(exifTiffHeaderOffset == expectedExifTiffHeaderOffset, AVIF_RESULT_INVALID_EXIF_PAYLOAD);
}
AVIF_CHECKRES(avifRWDataSet(&image->exif, avifROStreamCurrent(&exifBoxStream), avifROStreamRemainingBytes(&exifBoxStream)));
} else if (!decoder->ignoreXMP && !memcmp(item->type, "mime", 4) &&
!strcmp(item->contentType.contentType, AVIF_CONTENT_TYPE_XMP)) {
avifROData xmpContents;
avifResult readResult = avifDecoderItemRead(item, decoder->io, &xmpContents, 0, 0, &decoder->diag);
if (readResult != AVIF_RESULT_OK) {
return readResult;
}
AVIF_CHECKRES(avifImageSetMetadataXMP(image, xmpContents.data, xmpContents.size));
}
}
return AVIF_RESULT_OK;
}
// ---------------------------------------------------------------------------
// URN
static avifBool isAlphaURN(const char * urn)
{
return !strcmp(urn, AVIF_URN_ALPHA0) || !strcmp(urn, AVIF_URN_ALPHA1);
}
// ---------------------------------------------------------------------------
// BMFF Parsing
static avifBool avifParseHandlerBox(const uint8_t * raw, size_t rawLen, avifDiagnostics * diag)
{
BEGIN_STREAM(s, raw, rawLen, diag, "Box[hdlr]");
AVIF_CHECK(avifROStreamReadAndEnforceVersion(&s, 0));
uint32_t predefined;
AVIF_CHECK(avifROStreamReadU32(&s, &predefined)); // unsigned int(32) pre_defined = 0;
if (predefined != 0) {
avifDiagnosticsPrintf(diag, "Box[hdlr] contains a pre_defined value that is nonzero");
return AVIF_FALSE;
}
uint8_t handlerType[4];
AVIF_CHECK(avifROStreamRead(&s, handlerType, 4)); // unsigned int(32) handler_type;
if (memcmp(handlerType, "pict", 4) != 0) {
avifDiagnosticsPrintf(diag, "Box[hdlr] handler_type is not 'pict'");
return AVIF_FALSE;
}
for (int i = 0; i < 3; ++i) {
uint32_t reserved;
AVIF_CHECK(avifROStreamReadU32(&s, &reserved)); // const unsigned int(32)[3] reserved = 0;
}
// Verify that a valid string is here, but don't bother to store it
AVIF_CHECK(avifROStreamReadString(&s, NULL, 0)); // string name;
return AVIF_TRUE;
}
static avifResult avifParseItemLocationBox(avifMeta * meta, const uint8_t * raw, size_t rawLen, avifDiagnostics * diag)
{
BEGIN_STREAM(s, raw, rawLen, diag, "Box[iloc]");
// Section 8.11.3.2 of ISO/IEC 14496-12.
uint8_t version;
AVIF_CHECKERR(avifROStreamReadVersionAndFlags(&s, &version, NULL), AVIF_RESULT_BMFF_PARSE_FAILED);
if (version > 2) {
avifDiagnosticsPrintf(diag, "Box[iloc] has an unsupported version [%u]", version);
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
uint8_t offsetSize, lengthSize, baseOffsetSize, indexSize = 0;
uint32_t reserved;
AVIF_CHECKERR(avifROStreamReadBits8(&s, &offsetSize, /*bitCount=*/4), AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(4) offset_size;
AVIF_CHECKERR(avifROStreamReadBits8(&s, &lengthSize, /*bitCount=*/4), AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(4) length_size;
AVIF_CHECKERR(avifROStreamReadBits8(&s, &baseOffsetSize, /*bitCount=*/4), AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(4) base_offset_size;
if (version == 1 || version == 2) {
AVIF_CHECKERR(avifROStreamReadBits8(&s, &indexSize, /*bitCount=*/4), AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(4) index_size;
} else {
AVIF_CHECKERR(avifROStreamReadBits(&s, &reserved, /*bitCount=*/4), AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(4) reserved;
}
// Section 8.11.3.3 of ISO/IEC 14496-12.
if ((offsetSize != 0 && offsetSize != 4 && offsetSize != 8) || (lengthSize != 0 && lengthSize != 4 && lengthSize != 8) ||
(baseOffsetSize != 0 && baseOffsetSize != 4 && baseOffsetSize != 8) || (indexSize != 0 && indexSize != 4 && indexSize != 8)) {
avifDiagnosticsPrintf(diag, "Box[iloc] has an invalid size");
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
uint16_t tmp16;
uint32_t itemCount;
if (version < 2) {
AVIF_CHECKERR(avifROStreamReadU16(&s, &tmp16), AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(16) item_count;
itemCount = tmp16;
} else {
AVIF_CHECKERR(avifROStreamReadU32(&s, &itemCount), AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(32) item_count;
}
for (uint32_t i = 0; i < itemCount; ++i) {
uint32_t itemID;
if (version < 2) {
AVIF_CHECKERR(avifROStreamReadU16(&s, &tmp16), AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(16) item_ID;
itemID = tmp16;
} else {
AVIF_CHECKERR(avifROStreamReadU32(&s, &itemID), AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(32) item_ID;
}
AVIF_CHECKRES(avifCheckItemID("iloc", itemID, diag));
avifDecoderItem * item;
AVIF_CHECKRES(avifMetaFindOrCreateItem(meta, itemID, &item));
if (item->extents.count > 0) {
// This item has already been given extents via this iloc box. This is invalid.
avifDiagnosticsPrintf(diag, "Item ID [%u] contains duplicate sets of extents", itemID);
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
if (version == 1 || version == 2) {
AVIF_CHECKERR(avifROStreamReadBits(&s, &reserved, /*bitCount=*/12), AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(12) reserved = 0;
if (reserved) {
avifDiagnosticsPrintf(diag, "Box[iloc] has a non null reserved field [%u]", reserved);
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
uint8_t constructionMethod;
AVIF_CHECKERR(avifROStreamReadBits8(&s, &constructionMethod, /*bitCount=*/4),
AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(4) construction_method;
if (constructionMethod != 0 /* file offset */ && constructionMethod != 1 /* idat offset */) {
// construction method 2 (item offset) unsupported
avifDiagnosticsPrintf(diag, "Box[iloc] has an unsupported construction method [%u]", constructionMethod);
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
if (constructionMethod == 1) {
item->idatStored = AVIF_TRUE;
}
}
uint16_t dataReferenceIndex;
AVIF_CHECKERR(avifROStreamReadU16(&s, &dataReferenceIndex), AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(16) data_reference_index;
uint64_t baseOffset;
AVIF_CHECKERR(avifROStreamReadUX8(&s, &baseOffset, baseOffsetSize), AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(base_offset_size*8) base_offset;
uint16_t extentCount;
AVIF_CHECKERR(avifROStreamReadU16(&s, &extentCount), AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(16) extent_count;
for (int extentIter = 0; extentIter < extentCount; ++extentIter) {
if ((version == 1 || version == 2) && indexSize > 0) {
// Section 8.11.3.1 of ISO/IEC 14496-12:
// The item_reference_index is only used for the method item_offset; it indicates the 1-based index
// of the item reference with referenceType 'iloc' linked from this item. If index_size is 0, then
// the value 1 is implied; the value 0 is reserved.
uint64_t itemReferenceIndex; // Ignored unless construction_method=2 which is unsupported, but still read it.
AVIF_CHECKERR(avifROStreamReadUX8(&s, &itemReferenceIndex, indexSize),
AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(index_size*8) item_reference_index;
}
uint64_t extentOffset;
AVIF_CHECKERR(avifROStreamReadUX8(&s, &extentOffset, offsetSize), AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(offset_size*8) extent_offset;
uint64_t extentLength;
AVIF_CHECKERR(avifROStreamReadUX8(&s, &extentLength, lengthSize), AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(length_size*8) extent_length;
avifExtent * extent = (avifExtent *)avifArrayPush(&item->extents);
AVIF_CHECKERR(extent != NULL, AVIF_RESULT_OUT_OF_MEMORY);
if (extentOffset > UINT64_MAX - baseOffset) {
avifDiagnosticsPrintf(diag,
"Item ID [%u] contains an extent offset which overflows: [base: %" PRIu64 " offset:%" PRIu64 "]",
itemID,
baseOffset,
extentOffset);
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
uint64_t offset = baseOffset + extentOffset;
extent->offset = offset;
if (extentLength > SIZE_MAX) {
avifDiagnosticsPrintf(diag, "Item ID [%u] contains an extent length which overflows: [%" PRIu64 "]", itemID, extentLength);
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
extent->size = (size_t)extentLength;
if (extent->size > SIZE_MAX - item->size) {
avifDiagnosticsPrintf(diag,
"Item ID [%u] contains an extent length which overflows the item size: [%zu, %zu]",
itemID,
extent->size,
item->size);
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
item->size += extent->size;
}
}
return AVIF_RESULT_OK;
}
static avifBool avifParseImageGridBox(avifImageGrid * grid,
const uint8_t * raw,
size_t rawLen,
uint32_t imageSizeLimit,
uint32_t imageDimensionLimit,
avifDiagnostics * diag)
{
BEGIN_STREAM(s, raw, rawLen, diag, "Box[grid]");
uint8_t version, flags;
AVIF_CHECK(avifROStreamRead(&s, &version, 1)); // unsigned int(8) version = 0;
if (version != 0) {
avifDiagnosticsPrintf(diag, "Box[grid] has unsupported version [%u]", version);
return AVIF_FALSE;
}
uint8_t rowsMinusOne, columnsMinusOne;
AVIF_CHECK(avifROStreamRead(&s, &flags, 1)); // unsigned int(8) flags;
AVIF_CHECK(avifROStreamRead(&s, &rowsMinusOne, 1)); // unsigned int(8) rows_minus_one;
AVIF_CHECK(avifROStreamRead(&s, &columnsMinusOne, 1)); // unsigned int(8) columns_minus_one;
grid->rows = (uint32_t)rowsMinusOne + 1;
grid->columns = (uint32_t)columnsMinusOne + 1;
uint32_t fieldLength = ((flags & 1) + 1) * 16;
if (fieldLength == 16) {
uint16_t outputWidth16, outputHeight16;
AVIF_CHECK(avifROStreamReadU16(&s, &outputWidth16)); // unsigned int(FieldLength) output_width;
AVIF_CHECK(avifROStreamReadU16(&s, &outputHeight16)); // unsigned int(FieldLength) output_height;
grid->outputWidth = outputWidth16;
grid->outputHeight = outputHeight16;
} else {
if (fieldLength != 32) {
// This should be impossible
avifDiagnosticsPrintf(diag, "Grid box contains illegal field length: [%u]", fieldLength);
return AVIF_FALSE;
}
AVIF_CHECK(avifROStreamReadU32(&s, &grid->outputWidth)); // unsigned int(FieldLength) output_width;
AVIF_CHECK(avifROStreamReadU32(&s, &grid->outputHeight)); // unsigned int(FieldLength) output_height;
}
if ((grid->outputWidth == 0) || (grid->outputHeight == 0)) {
avifDiagnosticsPrintf(diag, "Grid box contains illegal dimensions: [%u x %u]", grid->outputWidth, grid->outputHeight);
return AVIF_FALSE;
}
if (avifDimensionsTooLarge(grid->outputWidth, grid->outputHeight, imageSizeLimit, imageDimensionLimit)) {
avifDiagnosticsPrintf(diag, "Grid box dimensions are too large: [%u x %u]", grid->outputWidth, grid->outputHeight);
return AVIF_FALSE;
}
return avifROStreamRemainingBytes(&s) == 0;
}
#if defined(AVIF_ENABLE_EXPERIMENTAL_GAIN_MAP)
static avifBool avifParseToneMappedImageBox(avifGainMapMetadata * metadata, const uint8_t * raw, size_t rawLen, avifDiagnostics * diag)
{
BEGIN_STREAM(s, raw, rawLen, diag, "Box[tmap]");
uint8_t version;
AVIF_CHECK(avifROStreamRead(&s, &version, 1)); // unsigned int(8) version = 0;
if (version != 0) {
avifDiagnosticsPrintf(diag, "Box[tmap] has unsupported version [%u]", version);
return AVIF_FALSE;
}
uint8_t flags;
AVIF_CHECK(avifROStreamRead(&s, &flags, 1)); // unsigned int(8) flags;
uint8_t channelCount = (flags & 1) * 2 + 1;
AVIF_ASSERT_OR_RETURN(channelCount == 1 || channelCount == 3);
metadata->useBaseColorSpace = (flags & 2) != 0;
const avifBool useCommonDenominator = (flags & 8) != 0;
if (useCommonDenominator) {
uint32_t commonDenominator;
AVIF_CHECK(avifROStreamReadU32(&s, &commonDenominator));
AVIF_CHECK(avifROStreamReadU32(&s, &metadata->baseHdrHeadroomN));
metadata->baseHdrHeadroomD = commonDenominator;
AVIF_CHECK(avifROStreamReadU32(&s, &metadata->alternateHdrHeadroomN));
metadata->alternateHdrHeadroomD = commonDenominator;
for (int c = 0; c < channelCount; ++c) {
AVIF_CHECK(avifROStreamReadU32(&s, (uint32_t *)&metadata->gainMapMinN[c]));
metadata->gainMapMinD[c] = commonDenominator;
AVIF_CHECK(avifROStreamReadU32(&s, (uint32_t *)&metadata->gainMapMaxN[c]));
metadata->gainMapMaxD[c] = commonDenominator;
AVIF_CHECK(avifROStreamReadU32(&s, &metadata->gainMapGammaN[c]));
metadata->gainMapGammaD[c] = commonDenominator;
AVIF_CHECK(avifROStreamReadU32(&s, (uint32_t *)&metadata->baseOffsetN[c]));
metadata->baseOffsetD[c] = commonDenominator;
AVIF_CHECK(avifROStreamReadU32(&s, (uint32_t *)&metadata->alternateOffsetN[c]));
metadata->alternateOffsetD[c] = commonDenominator;
}
} else {
AVIF_CHECK(avifROStreamReadU32(&s, &metadata->baseHdrHeadroomN));
AVIF_CHECK(avifROStreamReadU32(&s, &metadata->baseHdrHeadroomD));
AVIF_CHECK(avifROStreamReadU32(&s, &metadata->alternateHdrHeadroomN));
AVIF_CHECK(avifROStreamReadU32(&s, &metadata->alternateHdrHeadroomD));
for (int c = 0; c < channelCount; ++c) {
AVIF_CHECK(avifROStreamReadU32(&s, (uint32_t *)&metadata->gainMapMinN[c]));
AVIF_CHECK(avifROStreamReadU32(&s, &metadata->gainMapMinD[c]));
AVIF_CHECK(avifROStreamReadU32(&s, (uint32_t *)&metadata->gainMapMaxN[c]));
AVIF_CHECK(avifROStreamReadU32(&s, &metadata->gainMapMaxD[c]));
AVIF_CHECK(avifROStreamReadU32(&s, &metadata->gainMapGammaN[c]));
AVIF_CHECK(avifROStreamReadU32(&s, &metadata->gainMapGammaD[c]));
AVIF_CHECK(avifROStreamReadU32(&s, (uint32_t *)&metadata->baseOffsetN[c]));
AVIF_CHECK(avifROStreamReadU32(&s, &metadata->baseOffsetD[c]));
AVIF_CHECK(avifROStreamReadU32(&s, (uint32_t *)&metadata->alternateOffsetN[c]));
AVIF_CHECK(avifROStreamReadU32(&s, &metadata->alternateOffsetD[c]));
}
}
// Fill the remaining values by copying those from the first channel.
for (int c = channelCount; c < 3; ++c) {
metadata->gainMapMinN[c] = metadata->gainMapMinN[0];
metadata->gainMapMinD[c] = metadata->gainMapMinD[0];
metadata->gainMapMaxN[c] = metadata->gainMapMaxN[0];
metadata->gainMapMaxD[c] = metadata->gainMapMaxD[0];
metadata->gainMapGammaN[c] = metadata->gainMapGammaN[0];
metadata->gainMapGammaD[c] = metadata->gainMapGammaD[0];
metadata->baseOffsetN[c] = metadata->baseOffsetN[0];
metadata->baseOffsetD[c] = metadata->baseOffsetD[0];
metadata->alternateOffsetN[c] = metadata->alternateOffsetN[0];
metadata->alternateOffsetD[c] = metadata->alternateOffsetD[0];
}
return avifROStreamRemainingBytes(&s) == 0;
}
#endif // AVIF_ENABLE_EXPERIMENTAL_GAIN_MAP
#if defined(AVIF_ENABLE_EXPERIMENTAL_SAMPLE_TRANSFORM)
// bit_depth is assumed to be 2 (32-bit).
static avifResult avifParseSampleTransformTokens(avifROStream * s, avifSampleTransformExpression * expression)
{
uint8_t tokenCount;
AVIF_CHECK(avifROStreamRead(s, &tokenCount, /*size=*/1)); // unsigned int(8) token_count;
AVIF_CHECKERR(tokenCount != 0, AVIF_RESULT_BMFF_PARSE_FAILED);
AVIF_CHECKERR(avifArrayCreate(expression, sizeof(expression->tokens[0]), tokenCount), AVIF_RESULT_OUT_OF_MEMORY);
for (uint32_t t = 0; t < tokenCount; ++t) {
avifSampleTransformToken * token = (avifSampleTransformToken *)avifArrayPush(expression);
AVIF_CHECKERR(token != NULL, AVIF_RESULT_OUT_OF_MEMORY);
AVIF_CHECK(avifROStreamRead(s, &token->type, /*size=*/1)); // unsigned int(8) token;
if (token->type == AVIF_SAMPLE_TRANSFORM_CONSTANT) {
// Two's complement representation is assumed here.
uint32_t constant;
AVIF_CHECK(avifROStreamReadU32(s, &constant)); // signed int(1<<(bit_depth+3)) constant;
token->constant = *(int32_t *)&constant; // maybe =(int32_t)constant; is enough
} else if (token->type == AVIF_SAMPLE_TRANSFORM_INPUT_IMAGE_ITEM_INDEX) {
AVIF_CHECK(avifROStreamRead(s, &token->inputImageItemIndex, 1)); // unsigned int(8) input_image_item_index;
}
}
AVIF_CHECKERR(avifROStreamRemainingBytes(s) == 0, AVIF_RESULT_BMFF_PARSE_FAILED);
return AVIF_RESULT_OK;
}
// Parses the raw bitstream of the 'sato' Sample Transform derived image item and extracts the expression.
static avifResult avifParseSampleTransformImageBox(const uint8_t * raw,
size_t rawLen,
uint32_t numInputImageItems,
avifSampleTransformExpression * expression,
avifDiagnostics * diag)
{
BEGIN_STREAM(s, raw, rawLen, diag, "Box[sato]");
uint8_t version, bitDepth;
AVIF_CHECK(avifROStreamReadBits8(&s, &version, /*bitCount=*/6)); // unsigned int(6) version = 0;
AVIF_CHECK(avifROStreamReadBits8(&s, &bitDepth, /*bitCount=*/2)); // unsigned int(2) bit_depth;
AVIF_CHECKERR(version == 0, AVIF_RESULT_NOT_IMPLEMENTED);
AVIF_CHECKERR(bitDepth == AVIF_SAMPLE_TRANSFORM_BIT_DEPTH_32, AVIF_RESULT_NOT_IMPLEMENTED);
const avifResult result = avifParseSampleTransformTokens(&s, expression);
if (result != AVIF_RESULT_OK) {
avifArrayDestroy(expression);
return result;
}
if (!avifSampleTransformExpressionIsValid(expression, numInputImageItems)) {
avifArrayDestroy(expression);
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
return AVIF_RESULT_OK;
}
static avifResult avifDecoderSampleTransformItemValidateProperties(const avifDecoderItem * item, avifDiagnostics * diag)
{
const avifProperty * pixiProp = avifPropertyArrayFind(&item->properties, "pixi");
if (!pixiProp) {
avifDiagnosticsPrintf(diag, "Item ID %u of type '%.4s' is missing mandatory pixi property", item->id, (const char *)item->type);
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
for (uint8_t i = 0; i < pixiProp->u.pixi.planeCount; ++i) {
if (pixiProp->u.pixi.planeDepths[i] != pixiProp->u.pixi.planeDepths[0]) {
avifDiagnosticsPrintf(diag,
"Item ID %u of type '%.4s' has different depths specified by pixi property [%u, %u], this is not supported",
item->id,
(const char *)item->type,
pixiProp->u.pixi.planeDepths[0],
pixiProp->u.pixi.planeDepths[i]);
return AVIF_RESULT_NOT_IMPLEMENTED;
}
}
const avifProperty * ispeProp = avifPropertyArrayFind(&item->properties, "ispe");
if (!ispeProp) {
avifDiagnosticsPrintf(diag, "Item ID %u of type '%.4s' is missing mandatory ispe property", item->id, (const char *)item->type);
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
for (uint32_t i = 0; i < item->meta->items.count; ++i) {
avifDecoderItem * inputImageItem = item->meta->items.item[i];
if (inputImageItem->dimgForID != item->id) {
continue;
}
// Even if inputImageItem is a grid, the ispe property from its first tile should have been copied to the grid item.
const avifProperty * inputImageItemIspeProp = avifPropertyArrayFind(&inputImageItem->properties, "ispe");
AVIF_ASSERT_OR_RETURN(inputImageItemIspeProp != NULL);
if (inputImageItemIspeProp->u.ispe.width != ispeProp->u.ispe.width ||
inputImageItemIspeProp->u.ispe.height != ispeProp->u.ispe.height) {
avifDiagnosticsPrintf(diag,
"The fields of the ispe property of item ID %u of type '%.4s' differs from item ID %u",
inputImageItem->id,
(const char *)inputImageItem->type,
item->id);
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
// TODO(yguyon): Check that all input image items share the same codec config (except for the bit depth value).
}
AVIF_CHECKERR(avifPropertyArrayFind(&item->properties, "clap") == NULL, AVIF_RESULT_NOT_IMPLEMENTED);
return AVIF_RESULT_OK;
}
#endif // AVIF_ENABLE_EXPERIMENTAL_SAMPLE_TRANSFORM
// Extracts the codecType from the item type or from its children.
// Also parses and outputs grid information if the item is a grid.
// isItemInInput must be false if the item is a made-up structure
// (and thus not part of the parseable input bitstream).
static avifResult avifDecoderItemReadAndParse(const avifDecoder * decoder,
avifDecoderItem * item,
avifBool isItemInInput,
avifImageGrid * grid,
avifCodecType * codecType)
{
if (!memcmp(item->type, "grid", 4)) {
if (isItemInInput) {
avifROData readData;
AVIF_CHECKRES(avifDecoderItemRead(item, decoder->io, &readData, 0, 0, decoder->data->diag));
AVIF_CHECKERR(avifParseImageGridBox(grid,
readData.data,
readData.size,
decoder->imageSizeLimit,
decoder->imageDimensionLimit,
decoder->data->diag),
AVIF_RESULT_INVALID_IMAGE_GRID);
// Validate that there are exactly the same number of dimg items to form the grid.
uint32_t dimgItemCount = 0;
for (uint32_t i = 0; i < item->meta->items.count; ++i) {
if (item->meta->items.item[i]->dimgForID == item->id) {
++dimgItemCount;
}
}
if (dimgItemCount != grid->rows * grid->columns) {
return AVIF_RESULT_INVALID_IMAGE_GRID;
}
} else {
// item was generated for convenience and is not part of the bitstream.
// grid information should already be set.
AVIF_ASSERT_OR_RETURN(grid->rows > 0 && grid->columns > 0);
}
*codecType = avifDecoderItemGetGridCodecType(item);
AVIF_CHECKERR(*codecType != AVIF_CODEC_TYPE_UNKNOWN, AVIF_RESULT_INVALID_IMAGE_GRID);
} else {
*codecType = avifGetCodecType(item->type);
AVIF_ASSERT_OR_RETURN(*codecType != AVIF_CODEC_TYPE_UNKNOWN);
}
// TODO(yguyon): If AVIF_ENABLE_EXPERIMENTAL_SAMPLE_TRANSFORM is defined, backward-incompatible
// files with a primary 'sato' Sample Transform derived image item could be
// handled here (compared to backward-compatible files with a 'sato' item in the
// same 'altr' group as the primary regular color item which are handled in
// avifDecoderDataFindSampleTransformImageItem() below).
return AVIF_RESULT_OK;
}
static avifBool avifParseImageSpatialExtentsProperty(avifProperty * prop, const uint8_t * raw, size_t rawLen, avifDiagnostics * diag)
{
BEGIN_STREAM(s, raw, rawLen, diag, "Box[ispe]");
AVIF_CHECK(avifROStreamReadAndEnforceVersion(&s, 0));
avifImageSpatialExtents * ispe = &prop->u.ispe;
AVIF_CHECK(avifROStreamReadU32(&s, &ispe->width));
AVIF_CHECK(avifROStreamReadU32(&s, &ispe->height));
return AVIF_TRUE;
}
static avifBool avifParseAuxiliaryTypeProperty(avifProperty * prop, const uint8_t * raw, size_t rawLen, avifDiagnostics * diag)
{
BEGIN_STREAM(s, raw, rawLen, diag, "Box[auxC]");
AVIF_CHECK(avifROStreamReadAndEnforceVersion(&s, 0));
AVIF_CHECK(avifROStreamReadString(&s, prop->u.auxC.auxType, AUXTYPE_SIZE));
return AVIF_TRUE;
}
static avifBool avifParseColourInformationBox(avifProperty * prop, uint64_t rawOffset, const uint8_t * raw, size_t rawLen, avifDiagnostics * diag)
{
BEGIN_STREAM(s, raw, rawLen, diag, "Box[colr]");
avifColourInformationBox * colr = &prop->u.colr;
colr->hasICC = AVIF_FALSE;
colr->hasNCLX = AVIF_FALSE;
uint8_t colorType[4]; // unsigned int(32) colour_type;
AVIF_CHECK(avifROStreamRead(&s, colorType, 4));
if (!memcmp(colorType, "rICC", 4) || !memcmp(colorType, "prof", 4)) {
colr->hasICC = AVIF_TRUE;
// Remember the offset of the ICC payload relative to the beginning of the stream. A direct pointer cannot be stored
// because decoder->io->persistent could have been AVIF_FALSE when obtaining raw through decoder->io->read().
// The bytes could be copied now instead of remembering the offset, but it is as invasive as passing rawOffset everywhere.
colr->iccOffset = rawOffset + avifROStreamOffset(&s);
colr->iccSize = avifROStreamRemainingBytes(&s);
} else if (!memcmp(colorType, "nclx", 4)) {
AVIF_CHECK(avifROStreamReadU16(&s, &colr->colorPrimaries)); // unsigned int(16) colour_primaries;
AVIF_CHECK(avifROStreamReadU16(&s, &colr->transferCharacteristics)); // unsigned int(16) transfer_characteristics;
AVIF_CHECK(avifROStreamReadU16(&s, &colr->matrixCoefficients)); // unsigned int(16) matrix_coefficients;
uint8_t full_range_flag;
AVIF_CHECK(avifROStreamReadBits8(&s, &full_range_flag, /*bitCount=*/1)); // unsigned int(1) full_range_flag;
colr->range = full_range_flag ? AVIF_RANGE_FULL : AVIF_RANGE_LIMITED;
uint8_t reserved;
AVIF_CHECK(avifROStreamReadBits8(&s, &reserved, /*bitCount=*/7)); // unsigned int(7) reserved = 0;
if (reserved) {
avifDiagnosticsPrintf(diag, "Box[colr] contains nonzero reserved bits [%u]", reserved);
return AVIF_FALSE;
}
colr->hasNCLX = AVIF_TRUE;
}
return AVIF_TRUE;
}
static avifBool avifParseContentLightLevelInformationBox(avifProperty * prop, const uint8_t * raw, size_t rawLen, avifDiagnostics * diag)
{
BEGIN_STREAM(s, raw, rawLen, diag, "Box[clli]");
avifContentLightLevelInformationBox * clli = &prop->u.clli;
AVIF_CHECK(avifROStreamReadU16(&s, &clli->maxCLL)); // unsigned int(16) max_content_light_level
AVIF_CHECK(avifROStreamReadU16(&s, &clli->maxPALL)); // unsigned int(16) max_pic_average_light_level
return AVIF_TRUE;
}
// Implementation of section 2.3.3 of AV1 Codec ISO Media File Format Binding specification v1.2.0.
// See https://aomediacodec.github.io/av1-isobmff/v1.2.0.html#av1codecconfigurationbox-syntax.
static avifBool avifParseCodecConfiguration(avifROStream * s, avifCodecConfigurationBox * config, const char * configPropName, avifDiagnostics * diag)
{
uint32_t marker, version;
AVIF_CHECK(avifROStreamReadBits(s, &marker, /*bitCount=*/1)); // unsigned int (1) marker = 1;
if (!marker) {
avifDiagnosticsPrintf(diag, "%.4s contains illegal marker: [%u]", configPropName, marker);
return AVIF_FALSE;
}
AVIF_CHECK(avifROStreamReadBits(s, &version, /*bitCount=*/7)); // unsigned int (7) version = 1;
if (version != 1) {
avifDiagnosticsPrintf(diag, "%.4s contains illegal version: [%u]", configPropName, version);
return AVIF_FALSE;
}
AVIF_CHECK(avifROStreamReadBits8(s, &config->seqProfile, /*bitCount=*/3)); // unsigned int (3) seq_profile;
AVIF_CHECK(avifROStreamReadBits8(s, &config->seqLevelIdx0, /*bitCount=*/5)); // unsigned int (5) seq_level_idx_0;
AVIF_CHECK(avifROStreamReadBits8(s, &config->seqTier0, /*bitCount=*/1)); // unsigned int (1) seq_tier_0;
AVIF_CHECK(avifROStreamReadBits8(s, &config->highBitdepth, /*bitCount=*/1)); // unsigned int (1) high_bitdepth;
AVIF_CHECK(avifROStreamReadBits8(s, &config->twelveBit, /*bitCount=*/1)); // unsigned int (1) twelve_bit;
AVIF_CHECK(avifROStreamReadBits8(s, &config->monochrome, /*bitCount=*/1)); // unsigned int (1) monochrome;
AVIF_CHECK(avifROStreamReadBits8(s, &config->chromaSubsamplingX, /*bitCount=*/1)); // unsigned int (1) chroma_subsampling_x;
AVIF_CHECK(avifROStreamReadBits8(s, &config->chromaSubsamplingY, /*bitCount=*/1)); // unsigned int (1) chroma_subsampling_y;
AVIF_CHECK(avifROStreamReadBits8(s, &config->chromaSamplePosition, /*bitCount=*/2)); // unsigned int (2) chroma_sample_position;
// unsigned int (3) reserved = 0;
// unsigned int (1) initial_presentation_delay_present;
// if (initial_presentation_delay_present) {
// unsigned int (4) initial_presentation_delay_minus_one;
// } else {
// unsigned int (4) reserved = 0;
// }
AVIF_CHECK(avifROStreamSkip(s, /*byteCount=*/1));
// According to section 2.2.1 of AV1 Image File Format specification v1.1.0:
// - Sequence Header OBUs should not be present in the AV1CodecConfigurationBox.
// - If a Sequence Header OBU is present in the AV1CodecConfigurationBox,
// it shall match the Sequence Header OBU in the AV1 Image Item Data.
// - Metadata OBUs, if present, shall match the values given in other item properties,
// such as the PixelInformationProperty or ColourInformationBox.
// See https://aomediacodec.github.io/av1-avif/v1.1.0.html#av1-configuration-item-property.
// For simplicity, the constraints above are not enforced.
// The following is skipped by avifParseItemPropertyContainerBox().
// unsigned int (8) configOBUs[];
return AVIF_TRUE;
}
static avifBool avifParseCodecConfigurationBoxProperty(avifProperty * prop,
const uint8_t * raw,
size_t rawLen,
const char * configPropName,
avifDiagnostics * diag)
{
char diagContext[10];
snprintf(diagContext, sizeof(diagContext), "Box[%.4s]", configPropName); // "Box[av1C]" or "Box[av2C]"
BEGIN_STREAM(s, raw, rawLen, diag, diagContext);
return avifParseCodecConfiguration(&s, &prop->u.av1C, configPropName, diag);
}
static avifBool avifParsePixelAspectRatioBoxProperty(avifProperty * prop, const uint8_t * raw, size_t rawLen, avifDiagnostics * diag)
{
BEGIN_STREAM(s, raw, rawLen, diag, "Box[pasp]");
avifPixelAspectRatioBox * pasp = &prop->u.pasp;
AVIF_CHECK(avifROStreamReadU32(&s, &pasp->hSpacing)); // unsigned int(32) hSpacing;
AVIF_CHECK(avifROStreamReadU32(&s, &pasp->vSpacing)); // unsigned int(32) vSpacing;
return AVIF_TRUE;
}
static avifBool avifParseCleanApertureBoxProperty(avifProperty * prop, const uint8_t * raw, size_t rawLen, avifDiagnostics * diag)
{
BEGIN_STREAM(s, raw, rawLen, diag, "Box[clap]");
avifCleanApertureBox * clap = &prop->u.clap;
AVIF_CHECK(avifROStreamReadU32(&s, &clap->widthN)); // unsigned int(32) cleanApertureWidthN;
AVIF_CHECK(avifROStreamReadU32(&s, &clap->widthD)); // unsigned int(32) cleanApertureWidthD;
AVIF_CHECK(avifROStreamReadU32(&s, &clap->heightN)); // unsigned int(32) cleanApertureHeightN;
AVIF_CHECK(avifROStreamReadU32(&s, &clap->heightD)); // unsigned int(32) cleanApertureHeightD;
AVIF_CHECK(avifROStreamReadU32(&s, &clap->horizOffN)); // unsigned int(32) horizOffN;
AVIF_CHECK(avifROStreamReadU32(&s, &clap->horizOffD)); // unsigned int(32) horizOffD;
AVIF_CHECK(avifROStreamReadU32(&s, &clap->vertOffN)); // unsigned int(32) vertOffN;
AVIF_CHECK(avifROStreamReadU32(&s, &clap->vertOffD)); // unsigned int(32) vertOffD;
return AVIF_TRUE;
}
static avifBool avifParseImageRotationProperty(avifProperty * prop, const uint8_t * raw, size_t rawLen, avifDiagnostics * diag)
{
BEGIN_STREAM(s, raw, rawLen, diag, "Box[irot]");
avifImageRotation * irot = &prop->u.irot;
uint8_t reserved;
AVIF_CHECK(avifROStreamReadBits8(&s, &reserved, /*bitCount=*/6)); // unsigned int (6) reserved = 0;
if (reserved) {
avifDiagnosticsPrintf(diag, "Box[irot] contains nonzero reserved bits [%u]", reserved);
return AVIF_FALSE;
}
AVIF_CHECK(avifROStreamReadBits8(&s, &irot->angle, /*bitCount=*/2)); // unsigned int (2) angle;
return AVIF_TRUE;
}
static avifBool avifParseImageMirrorProperty(avifProperty * prop, const uint8_t * raw, size_t rawLen, avifDiagnostics * diag)
{
BEGIN_STREAM(s, raw, rawLen, diag, "Box[imir]");
avifImageMirror * imir = &prop->u.imir;
uint8_t reserved;
AVIF_CHECK(avifROStreamReadBits8(&s, &reserved, /*bitCount=*/7)); // unsigned int(7) reserved = 0;
if (reserved) {
avifDiagnosticsPrintf(diag, "Box[imir] contains nonzero reserved bits [%u]", reserved);
return AVIF_FALSE;
}
AVIF_CHECK(avifROStreamReadBits8(&s, &imir->axis, /*bitCount=*/1)); // unsigned int(1) axis;
return AVIF_TRUE;
}
static avifBool avifParsePixelInformationProperty(avifProperty * prop, const uint8_t * raw, size_t rawLen, avifDiagnostics * diag)
{
BEGIN_STREAM(s, raw, rawLen, diag, "Box[pixi]");
AVIF_CHECK(avifROStreamReadAndEnforceVersion(&s, 0));
avifPixelInformationProperty * pixi = &prop->u.pixi;
AVIF_CHECK(avifROStreamRead(&s, &pixi->planeCount, 1)); // unsigned int (8) num_channels;
if (pixi->planeCount < 1 || pixi->planeCount > MAX_PIXI_PLANE_DEPTHS) {
avifDiagnosticsPrintf(diag, "Box[pixi] contains unsupported plane count [%u]", pixi->planeCount);
return AVIF_FALSE;
}
for (uint8_t i = 0; i < pixi->planeCount; ++i) {
AVIF_CHECK(avifROStreamRead(&s, &pixi->planeDepths[i], 1)); // unsigned int (8) bits_per_channel;
if (pixi->planeDepths[i] != pixi->planeDepths[0]) {
avifDiagnosticsPrintf(diag,
"Box[pixi] contains unsupported mismatched plane depths [%u != %u]",
pixi->planeDepths[i],
pixi->planeDepths[0]);
return AVIF_FALSE;
}
}
return AVIF_TRUE;
}
static avifBool avifParseOperatingPointSelectorProperty(avifProperty * prop, const uint8_t * raw, size_t rawLen, avifDiagnostics * diag)
{
BEGIN_STREAM(s, raw, rawLen, diag, "Box[a1op]");
avifOperatingPointSelectorProperty * a1op = &prop->u.a1op;
AVIF_CHECK(avifROStreamRead(&s, &a1op->opIndex, 1));
if (a1op->opIndex > 31) { // 31 is AV1's max operating point value
avifDiagnosticsPrintf(diag, "Box[a1op] contains an unsupported operating point [%u]", a1op->opIndex);
return AVIF_FALSE;
}
return AVIF_TRUE;
}
static avifBool avifParseLayerSelectorProperty(avifProperty * prop, const uint8_t * raw, size_t rawLen, avifDiagnostics * diag)
{
BEGIN_STREAM(s, raw, rawLen, diag, "Box[lsel]");
avifLayerSelectorProperty * lsel = &prop->u.lsel;
AVIF_CHECK(avifROStreamReadU16(&s, &lsel->layerID));
if ((lsel->layerID != 0xFFFF) && (lsel->layerID >= AVIF_MAX_AV1_LAYER_COUNT)) {
avifDiagnosticsPrintf(diag, "Box[lsel] contains an unsupported layer [%u]", lsel->layerID);
return AVIF_FALSE;
}
return AVIF_TRUE;
}
static avifBool avifParseAV1LayeredImageIndexingProperty(avifProperty * prop, const uint8_t * raw, size_t rawLen, avifDiagnostics * diag)
{
BEGIN_STREAM(s, raw, rawLen, diag, "Box[a1lx]");
avifAV1LayeredImageIndexingProperty * a1lx = &prop->u.a1lx;
uint8_t largeSize = 0;
AVIF_CHECK(avifROStreamRead(&s, &largeSize, 1));
if (largeSize & 0xFE) {
avifDiagnosticsPrintf(diag, "Box[a1lx] has bits set in the reserved section [%u]", largeSize);
return AVIF_FALSE;
}
for (int i = 0; i < 3; ++i) {
if (largeSize) {
AVIF_CHECK(avifROStreamReadU32(&s, &a1lx->layerSize[i]));
} else {
uint16_t layerSize16;
AVIF_CHECK(avifROStreamReadU16(&s, &layerSize16));
a1lx->layerSize[i] = (uint32_t)layerSize16;
}
}
// Layer sizes will be validated later (when the item's size is known)
return AVIF_TRUE;
}
static avifResult avifParseItemPropertyContainerBox(avifPropertyArray * properties,
uint64_t rawOffset,
const uint8_t * raw,
size_t rawLen,
avifDiagnostics * diag)
{
BEGIN_STREAM(s, raw, rawLen, diag, "Box[ipco]");
while (avifROStreamHasBytesLeft(&s, 1)) {
avifBoxHeader header;
AVIF_CHECKERR(avifROStreamReadBoxHeader(&s, &header), AVIF_RESULT_BMFF_PARSE_FAILED);
avifProperty * prop = (avifProperty *)avifArrayPush(properties);
AVIF_CHECKERR(prop != NULL, AVIF_RESULT_OUT_OF_MEMORY);
memcpy(prop->type, header.type, 4);
if (!memcmp(header.type, "ispe", 4)) {
AVIF_CHECKERR(avifParseImageSpatialExtentsProperty(prop, avifROStreamCurrent(&s), header.size, diag),
AVIF_RESULT_BMFF_PARSE_FAILED);
} else if (!memcmp(header.type, "auxC", 4)) {
AVIF_CHECKERR(avifParseAuxiliaryTypeProperty(prop, avifROStreamCurrent(&s), header.size, diag), AVIF_RESULT_BMFF_PARSE_FAILED);
} else if (!memcmp(header.type, "colr", 4)) {
AVIF_CHECKERR(avifParseColourInformationBox(prop, rawOffset + avifROStreamOffset(&s), avifROStreamCurrent(&s), header.size, diag),
AVIF_RESULT_BMFF_PARSE_FAILED);
} else if (!memcmp(header.type, "av1C", 4)) {
AVIF_CHECKERR(avifParseCodecConfigurationBoxProperty(prop, avifROStreamCurrent(&s), header.size, "av1C", diag),
AVIF_RESULT_BMFF_PARSE_FAILED);
#if defined(AVIF_CODEC_AVM)
} else if (!memcmp(header.type, "av2C", 4)) {
AVIF_CHECKERR(avifParseCodecConfigurationBoxProperty(prop, avifROStreamCurrent(&s), header.size, "av2C", diag),
AVIF_RESULT_BMFF_PARSE_FAILED);
#endif
} else if (!memcmp(header.type, "pasp", 4)) {
AVIF_CHECKERR(avifParsePixelAspectRatioBoxProperty(prop, avifROStreamCurrent(&s), header.size, diag),
AVIF_RESULT_BMFF_PARSE_FAILED);
} else if (!memcmp(header.type, "clap", 4)) {
AVIF_CHECKERR(avifParseCleanApertureBoxProperty(prop, avifROStreamCurrent(&s), header.size, diag),
AVIF_RESULT_BMFF_PARSE_FAILED);
} else if (!memcmp(header.type, "irot", 4)) {
AVIF_CHECKERR(avifParseImageRotationProperty(prop, avifROStreamCurrent(&s), header.size, diag), AVIF_RESULT_BMFF_PARSE_FAILED);
} else if (!memcmp(header.type, "imir", 4)) {
AVIF_CHECKERR(avifParseImageMirrorProperty(prop, avifROStreamCurrent(&s), header.size, diag), AVIF_RESULT_BMFF_PARSE_FAILED);
} else if (!memcmp(header.type, "pixi", 4)) {
AVIF_CHECKERR(avifParsePixelInformationProperty(prop, avifROStreamCurrent(&s), header.size, diag),
AVIF_RESULT_BMFF_PARSE_FAILED);
} else if (!memcmp(header.type, "a1op", 4)) {
AVIF_CHECKERR(avifParseOperatingPointSelectorProperty(prop, avifROStreamCurrent(&s), header.size, diag),
AVIF_RESULT_BMFF_PARSE_FAILED);
} else if (!memcmp(header.type, "lsel", 4)) {
AVIF_CHECKERR(avifParseLayerSelectorProperty(prop, avifROStreamCurrent(&s), header.size, diag), AVIF_RESULT_BMFF_PARSE_FAILED);
} else if (!memcmp(header.type, "a1lx", 4)) {
AVIF_CHECKERR(avifParseAV1LayeredImageIndexingProperty(prop, avifROStreamCurrent(&s), header.size, diag),
AVIF_RESULT_BMFF_PARSE_FAILED);
} else if (!memcmp(header.type, "clli", 4)) {
AVIF_CHECKERR(avifParseContentLightLevelInformationBox(prop, avifROStreamCurrent(&s), header.size, diag),
AVIF_RESULT_BMFF_PARSE_FAILED);
}
AVIF_CHECKERR(avifROStreamSkip(&s, header.size), AVIF_RESULT_BMFF_PARSE_FAILED);
}
return AVIF_RESULT_OK;
}
static avifResult avifParseItemPropertyAssociation(avifMeta * meta, const uint8_t * raw, size_t rawLen, avifDiagnostics * diag, uint32_t * outVersionAndFlags)
{
// NOTE: If this function ever adds support for versions other than [0,1] or flags other than
// [0,1], please increase the value of MAX_IPMA_VERSION_AND_FLAGS_SEEN accordingly.
BEGIN_STREAM(s, raw, rawLen, diag, "Box[ipma]");
uint8_t version;
uint32_t flags;
AVIF_CHECKERR(avifROStreamReadVersionAndFlags(&s, &version, &flags), AVIF_RESULT_BMFF_PARSE_FAILED);
avifBool propertyIndexIsU15 = ((flags & 0x1) != 0);
*outVersionAndFlags = ((uint32_t)version << 24) | flags;
uint32_t entryCount;
AVIF_CHECKERR(avifROStreamReadU32(&s, &entryCount), AVIF_RESULT_BMFF_PARSE_FAILED);
unsigned int prevItemID = 0;
for (uint32_t entryIndex = 0; entryIndex < entryCount; ++entryIndex) {
// ISO/IEC 14496-12, Seventh edition, 2022-01, Section 8.11.14.1:
// Each ItemPropertyAssociationBox shall be ordered by increasing item_ID, and there shall
// be at most one occurrence of a given item_ID, in the set of ItemPropertyAssociationBox
// boxes.
unsigned int itemID;
if (version < 1) {
uint16_t tmp;
AVIF_CHECKERR(avifROStreamReadU16(&s, &tmp), AVIF_RESULT_BMFF_PARSE_FAILED);
itemID = tmp;
} else {
AVIF_CHECKERR(avifROStreamReadU32(&s, &itemID), AVIF_RESULT_BMFF_PARSE_FAILED);
}
AVIF_CHECKRES(avifCheckItemID("ipma", itemID, diag));
if (itemID <= prevItemID) {
avifDiagnosticsPrintf(diag, "Box[ipma] item IDs are not ordered by increasing ID");
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
prevItemID = itemID;
avifDecoderItem * item;
AVIF_CHECKRES(avifMetaFindOrCreateItem(meta, itemID, &item));
if (item->ipmaSeen) {
avifDiagnosticsPrintf(diag, "Duplicate Box[ipma] for item ID [%u]", itemID);
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
item->ipmaSeen = AVIF_TRUE;
uint8_t associationCount;
AVIF_CHECKERR(avifROStreamRead(&s, &associationCount, 1), AVIF_RESULT_BMFF_PARSE_FAILED);
for (uint8_t associationIndex = 0; associationIndex < associationCount; ++associationIndex) {
uint8_t essential;
AVIF_CHECKERR(avifROStreamReadBits8(&s, &essential, /*bitCount=*/1), AVIF_RESULT_BMFF_PARSE_FAILED); // bit(1) essential;
uint32_t propertyIndex;
AVIF_CHECKERR(avifROStreamReadBits(&s, &propertyIndex, /*bitCount=*/propertyIndexIsU15 ? 15 : 7),
AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(7/15) property_index;
if (propertyIndex == 0) {
// Not associated with any item
continue;
}
--propertyIndex; // 1-indexed
if (propertyIndex >= meta->properties.count) {
avifDiagnosticsPrintf(diag,
"Box[ipma] for item ID [%u] contains an illegal property index [%u] (out of [%u] properties)",
itemID,
propertyIndex,
meta->properties.count);
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
// Copy property to item
const avifProperty * srcProp = &meta->properties.prop[propertyIndex];
static const char * supportedTypes[] = {
"ispe",
"auxC",
"colr",
"av1C",
#if defined(AVIF_CODEC_AVM)
"av2C",
#endif
"pasp",
"clap",
"irot",
"imir",
"pixi",
"a1op",
"lsel",
"a1lx",
"clli"
};
size_t supportedTypesCount = sizeof(supportedTypes) / sizeof(supportedTypes[0]);
avifBool supportedType = AVIF_FALSE;
for (size_t i = 0; i < supportedTypesCount; ++i) {
if (!memcmp(srcProp->type, supportedTypes[i], 4)) {
supportedType = AVIF_TRUE;
break;
}
}
if (supportedType) {
if (essential) {
// Verify that it is legal for this property to be flagged as essential. Any
// types in this list are *required* in the spec to not be flagged as essential
// when associated with an item.
static const char * const nonessentialTypes[] = {
// AVIF: Section 2.3.2.3.2: "If associated, it shall not be marked as essential."
"a1lx"
};
size_t nonessentialTypesCount = sizeof(nonessentialTypes) / sizeof(nonessentialTypes[0]);
for (size_t i = 0; i < nonessentialTypesCount; ++i) {
if (!memcmp(srcProp->type, nonessentialTypes[i], 4)) {
avifDiagnosticsPrintf(diag,
"Item ID [%u] has a %s property association which must not be marked essential, but is",
itemID,
nonessentialTypes[i]);
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
}
} else {
// Verify that it is legal for this property to not be flagged as essential. Any
// types in this list are *required* in the spec to be flagged as essential when
// associated with an item.
static const char * const essentialTypes[] = {
// AVIF: Section 2.3.2.1.1: "If associated, it shall be marked as essential."
"a1op",
// HEIF: Section 6.5.11.1: "essential shall be equal to 1 for an 'lsel' item property."
"lsel"
};
size_t essentialTypesCount = sizeof(essentialTypes) / sizeof(essentialTypes[0]);
for (size_t i = 0; i < essentialTypesCount; ++i) {
if (!memcmp(srcProp->type, essentialTypes[i], 4)) {
avifDiagnosticsPrintf(diag,
"Item ID [%u] has a %s property association which must be marked essential, but is not",
itemID,
essentialTypes[i]);
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
}
}
// Supported and valid; associate it with this item.
avifProperty * dstProp = (avifProperty *)avifArrayPush(&item->properties);
AVIF_CHECKERR(dstProp != NULL, AVIF_RESULT_OUT_OF_MEMORY);
*dstProp = *srcProp;
} else {
if (essential) {
// Discovered an essential item property that libavif doesn't support!
// Make a note to ignore this item later.
item->hasUnsupportedEssentialProperty = AVIF_TRUE;
}
}
}
}
return AVIF_RESULT_OK;
}
static avifBool avifParsePrimaryItemBox(avifMeta * meta, const uint8_t * raw, size_t rawLen, avifDiagnostics * diag)
{
if (meta->primaryItemID > 0) {
// Illegal to have multiple pitm boxes, bail out
avifDiagnosticsPrintf(diag, "Multiple boxes of unique Box[pitm] found");
return AVIF_FALSE;
}
BEGIN_STREAM(s, raw, rawLen, diag, "Box[pitm]");
uint8_t version;
AVIF_CHECK(avifROStreamReadVersionAndFlags(&s, &version, NULL));
if (version == 0) {
uint16_t tmp16;
AVIF_CHECK(avifROStreamReadU16(&s, &tmp16)); // unsigned int(16) item_ID;
meta->primaryItemID = tmp16;
} else {
AVIF_CHECK(avifROStreamReadU32(&s, &meta->primaryItemID)); // unsigned int(32) item_ID;
}
return AVIF_TRUE;
}
static avifBool avifParseItemDataBox(avifMeta * meta, const uint8_t * raw, size_t rawLen, avifDiagnostics * diag)
{
// Check to see if we've already seen an idat box for this meta box. If so, bail out
if (meta->idat.size > 0) {
avifDiagnosticsPrintf(diag, "Meta box contains multiple idat boxes");
return AVIF_FALSE;
}
if (rawLen == 0) {
avifDiagnosticsPrintf(diag, "idat box has a length of 0");
return AVIF_FALSE;
}
if (avifRWDataSet(&meta->idat, raw, rawLen) != AVIF_RESULT_OK) {
return AVIF_FALSE;
}
return AVIF_TRUE;
}
static avifResult avifParseItemPropertiesBox(avifMeta * meta, uint64_t rawOffset, const uint8_t * raw, size_t rawLen, avifDiagnostics * diag)
{
BEGIN_STREAM(s, raw, rawLen, diag, "Box[iprp]");
avifBoxHeader ipcoHeader;
AVIF_CHECKERR(avifROStreamReadBoxHeader(&s, &ipcoHeader), AVIF_RESULT_BMFF_PARSE_FAILED);
if (memcmp(ipcoHeader.type, "ipco", 4)) {
avifDiagnosticsPrintf(diag, "Failed to find Box[ipco] as the first box in Box[iprp]");
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
// Read all item properties inside of ItemPropertyContainerBox
AVIF_CHECKRES(avifParseItemPropertyContainerBox(&meta->properties,
rawOffset + avifROStreamOffset(&s),
avifROStreamCurrent(&s),
ipcoHeader.size,
diag));
AVIF_CHECKERR(avifROStreamSkip(&s, ipcoHeader.size), AVIF_RESULT_BMFF_PARSE_FAILED);
uint32_t versionAndFlagsSeen[MAX_IPMA_VERSION_AND_FLAGS_SEEN];
uint32_t versionAndFlagsSeenCount = 0;
// Now read all ItemPropertyAssociation until the end of the box, and make associations
while (avifROStreamHasBytesLeft(&s, 1)) {
avifBoxHeader ipmaHeader;
AVIF_CHECKERR(avifROStreamReadBoxHeader(&s, &ipmaHeader), AVIF_RESULT_BMFF_PARSE_FAILED);
if (!memcmp(ipmaHeader.type, "ipma", 4)) {
uint32_t versionAndFlags;
AVIF_CHECKRES(avifParseItemPropertyAssociation(meta, avifROStreamCurrent(&s), ipmaHeader.size, diag, &versionAndFlags));
for (uint32_t i = 0; i < versionAndFlagsSeenCount; ++i) {
if (versionAndFlagsSeen[i] == versionAndFlags) {
// BMFF (ISO/IEC 14496-12:2022) 8.11.14.1 - There shall be at most one
// ItemPropertyAssociationBox with a given pair of values of version and
// flags.
avifDiagnosticsPrintf(diag, "Multiple Box[ipma] with a given pair of values of version and flags. See BMFF (ISO/IEC 14496-12:2022) 8.11.14.1");
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
}
if (versionAndFlagsSeenCount == MAX_IPMA_VERSION_AND_FLAGS_SEEN) {
avifDiagnosticsPrintf(diag, "Exceeded possible count of unique ipma version and flags tuples");
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
versionAndFlagsSeen[versionAndFlagsSeenCount] = versionAndFlags;
++versionAndFlagsSeenCount;
} else {
// These must all be type ipma
avifDiagnosticsPrintf(diag, "Box[iprp] contains a box that isn't type 'ipma'");
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
AVIF_CHECKERR(avifROStreamSkip(&s, ipmaHeader.size), AVIF_RESULT_BMFF_PARSE_FAILED);
}
return AVIF_RESULT_OK;
}
static avifResult avifParseItemInfoEntry(avifMeta * meta, const uint8_t * raw, size_t rawLen, avifDiagnostics * diag)
{
// Section 8.11.6.2 of ISO/IEC 14496-12.
BEGIN_STREAM(s, raw, rawLen, diag, "Box[infe]");
uint8_t version;
uint32_t flags;
AVIF_CHECKERR(avifROStreamReadVersionAndFlags(&s, &version, &flags), AVIF_RESULT_BMFF_PARSE_FAILED);
// Version 2+ is required for item_type
if (version != 2 && version != 3) {
avifDiagnosticsPrintf(s.diag, "%s: Expecting box version 2 or 3, got version %u", s.diagContext, version);
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
// TODO: check flags. ISO/IEC 23008-12:2017, Section 9.2 says:
// The flags field of ItemInfoEntry with version greater than or equal to 2 is specified as
// follows:
//
// (flags & 1) equal to 1 indicates that the item is not intended to be a part of the
// presentation. For example, when (flags & 1) is equal to 1 for an image item, the image
// item should not be displayed.
// (flags & 1) equal to 0 indicates that the item is intended to be a part of the
// presentation.
//
// See also Section 6.4.2.
uint32_t itemID;
if (version == 2) {
uint16_t tmp;
AVIF_CHECKERR(avifROStreamReadU16(&s, &tmp), AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(16) item_ID;
itemID = tmp;
} else {
AVIF_ASSERT_OR_RETURN(version == 3);
AVIF_CHECKERR(avifROStreamReadU32(&s, &itemID), AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(32) item_ID;
}
AVIF_CHECKRES(avifCheckItemID("infe", itemID, diag));
uint16_t itemProtectionIndex;
AVIF_CHECKERR(avifROStreamReadU16(&s, &itemProtectionIndex), AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(16) item_protection_index;
uint8_t itemType[4];
AVIF_CHECKERR(avifROStreamRead(&s, itemType, 4), AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(32) item_type;
AVIF_CHECKERR(avifROStreamReadString(&s, NULL, 0), AVIF_RESULT_BMFF_PARSE_FAILED); // utf8string item_name; (skipped)
avifContentType contentType;
if (!memcmp(itemType, "mime", 4)) {
AVIF_CHECKERR(avifROStreamReadString(&s, contentType.contentType, CONTENTTYPE_SIZE), AVIF_RESULT_BMFF_PARSE_FAILED); // utf8string content_type;
// utf8string content_encoding; //optional
} else {
// if (item_type == 'uri ') {
// utf8string item_uri_type;
// }
memset(&contentType, 0, sizeof(contentType));
}
avifDecoderItem * item;
AVIF_CHECKRES(avifMetaFindOrCreateItem(meta, itemID, &item));
memcpy(item->type, itemType, sizeof(itemType));
item->contentType = contentType;
return AVIF_RESULT_OK;
}
static avifResult avifParseItemInfoBox(avifMeta * meta, const uint8_t * raw, size_t rawLen, avifDiagnostics * diag)
{
BEGIN_STREAM(s, raw, rawLen, diag, "Box[iinf]");
uint8_t version;
AVIF_CHECKERR(avifROStreamReadVersionAndFlags(&s, &version, NULL), AVIF_RESULT_BMFF_PARSE_FAILED);
uint32_t entryCount;
if (version == 0) {
uint16_t tmp;
AVIF_CHECKERR(avifROStreamReadU16(&s, &tmp), AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(16) entry_count;
entryCount = tmp;
} else if (version == 1) {
AVIF_CHECKERR(avifROStreamReadU32(&s, &entryCount), AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(32) entry_count;
} else {
avifDiagnosticsPrintf(diag, "Box[iinf] has an unsupported version %u", version);
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
for (uint32_t entryIndex = 0; entryIndex < entryCount; ++entryIndex) {
avifBoxHeader infeHeader;
AVIF_CHECKERR(avifROStreamReadBoxHeader(&s, &infeHeader), AVIF_RESULT_BMFF_PARSE_FAILED);
if (!memcmp(infeHeader.type, "infe", 4)) {
AVIF_CHECKRES(avifParseItemInfoEntry(meta, avifROStreamCurrent(&s), infeHeader.size, diag));
} else {
// These must all be type infe
avifDiagnosticsPrintf(diag, "Box[iinf] contains a box that isn't type 'infe'");
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
AVIF_CHECKERR(avifROStreamSkip(&s, infeHeader.size), AVIF_RESULT_BMFF_PARSE_FAILED);
}
return AVIF_RESULT_OK;
}
static avifResult avifParseItemReferenceBox(avifMeta * meta, const uint8_t * raw, size_t rawLen, avifDiagnostics * diag)
{
BEGIN_STREAM(s, raw, rawLen, diag, "Box[iref]");
uint8_t version;
AVIF_CHECKERR(avifROStreamReadVersionAndFlags(&s, &version, NULL), AVIF_RESULT_BMFF_PARSE_FAILED);
if (version > 1) {
// iref versions > 1 are not supported. Skip it.
return AVIF_RESULT_OK;
}
while (avifROStreamHasBytesLeft(&s, 1)) {
avifBoxHeader irefHeader;
AVIF_CHECKERR(avifROStreamReadBoxHeader(&s, &irefHeader), AVIF_RESULT_BMFF_PARSE_FAILED);
uint32_t fromID = 0;
if (version == 0) {
uint16_t tmp;
AVIF_CHECKERR(avifROStreamReadU16(&s, &tmp), AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(16) from_item_ID;
fromID = tmp;
} else {
// version == 1
AVIF_CHECKERR(avifROStreamReadU32(&s, &fromID), AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(32) from_item_ID;
}
// ISO 14496-12 section 8.11.12.1: "index values start at 1"
AVIF_CHECKRES(avifCheckItemID("iref", fromID, diag));
avifDecoderItem * item;
AVIF_CHECKRES(avifMetaFindOrCreateItem(meta, fromID, &item));
if (!memcmp(irefHeader.type, "dimg", 4)) {
if (item->hasDimgFrom) {
// ISO/IEC 23008-12 (HEIF) 6.6.1: The number of SingleItemTypeReferenceBoxes with the box type 'dimg'
// and with the same value of from_item_ID shall not be greater than 1.
avifDiagnosticsPrintf(diag, "Box[iinf] contains duplicate boxes of type 'dimg' with the same from_item_ID value %d", fromID);
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
item->hasDimgFrom = AVIF_TRUE;
}
uint16_t referenceCount = 0;
AVIF_CHECKERR(avifROStreamReadU16(&s, &referenceCount), AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(16) reference_count;
for (uint16_t refIndex = 0; refIndex < referenceCount; ++refIndex) {
uint32_t toID = 0;
if (version == 0) {
uint16_t tmp;
AVIF_CHECKERR(avifROStreamReadU16(&s, &tmp), AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(16) to_item_ID;
toID = tmp;
} else {
// version == 1
AVIF_CHECKERR(avifROStreamReadU32(&s, &toID), AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(32) to_item_ID;
}
AVIF_CHECKRES(avifCheckItemID("iref", toID, diag));
// Read this reference as "{fromID} is a {irefType} for {toID}"
if (!memcmp(irefHeader.type, "thmb", 4)) {
item->thumbnailForID = toID;
} else if (!memcmp(irefHeader.type, "auxl", 4)) {
item->auxForID = toID;
} else if (!memcmp(irefHeader.type, "cdsc", 4)) {
item->descForID = toID;
} else if (!memcmp(irefHeader.type, "dimg", 4)) {
// derived images refer in the opposite direction
avifDecoderItem * dimg;
AVIF_CHECKRES(avifMetaFindOrCreateItem(meta, toID, &dimg));
dimg->dimgForID = fromID;
dimg->dimgIdx = refIndex;
} else if (!memcmp(irefHeader.type, "prem", 4)) {
item->premByID = toID;
}
}
}
return AVIF_RESULT_OK;
}
#if defined(AVIF_ENABLE_EXPERIMENTAL_METAV1)
static avifResult avifParseMetaBoxV1(avifROStream * s, avifMeta * meta, uint64_t rawOffset, uint32_t flags, avifDiagnostics * diag);
#endif
static avifResult avifParseMetaBox(avifMeta * meta, uint64_t rawOffset, const uint8_t * raw, size_t rawLen, avifDiagnostics * diag)
{
BEGIN_STREAM(s, raw, rawLen, diag, "Box[meta]");
uint8_t version;
uint32_t flags;
AVIF_CHECKERR(avifROStreamReadVersionAndFlags(&s, &version, &flags), AVIF_RESULT_BMFF_PARSE_FAILED);
#if defined(AVIF_ENABLE_EXPERIMENTAL_METAV1)
if (version == 1) {
// Experimental box.
AVIF_CHECKRES(avifParseMetaBoxV1(&s, meta, rawOffset, flags, diag));
return AVIF_RESULT_OK;
}
#endif
if (version != 0) {
avifDiagnosticsPrintf(diag, "Box[meta]: Expecting box version 0, got version %u", version);
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
++meta->idatID; // for tracking idat
avifBool firstBox = AVIF_TRUE;
uint32_t uniqueBoxFlags = 0;
while (avifROStreamHasBytesLeft(&s, 1)) {
avifBoxHeader header;
AVIF_CHECKERR(avifROStreamReadBoxHeader(&s, &header), AVIF_RESULT_BMFF_PARSE_FAILED);
if (firstBox) {
if (!memcmp(header.type, "hdlr", 4)) {
AVIF_CHECKERR(avifParseHandlerBox(avifROStreamCurrent(&s), header.size, diag), AVIF_RESULT_BMFF_PARSE_FAILED);
firstBox = AVIF_FALSE;
} else {
// hdlr must be the first box!
avifDiagnosticsPrintf(diag, "Box[meta] does not have a Box[hdlr] as its first child box");
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
} else if (!memcmp(header.type, "hdlr", 4)) {
avifDiagnosticsPrintf(diag, "Box[meta] contains a duplicate unique box of type 'hdlr'");
return AVIF_RESULT_BMFF_PARSE_FAILED;
} else if (!memcmp(header.type, "iloc", 4)) {
AVIF_CHECKERR(uniqueBoxSeen(&uniqueBoxFlags, 0, "meta", "iloc", diag), AVIF_RESULT_BMFF_PARSE_FAILED);
AVIF_CHECKRES(avifParseItemLocationBox(meta, avifROStreamCurrent(&s), header.size, diag));
} else if (!memcmp(header.type, "pitm", 4)) {
AVIF_CHECKERR(uniqueBoxSeen(&uniqueBoxFlags, 1, "meta", "pitm", diag), AVIF_RESULT_BMFF_PARSE_FAILED);
AVIF_CHECKERR(avifParsePrimaryItemBox(meta, avifROStreamCurrent(&s), header.size, diag), AVIF_RESULT_BMFF_PARSE_FAILED);
} else if (!memcmp(header.type, "idat", 4)) {
AVIF_CHECKERR(uniqueBoxSeen(&uniqueBoxFlags, 2, "meta", "idat", diag), AVIF_RESULT_BMFF_PARSE_FAILED);
AVIF_CHECKERR(avifParseItemDataBox(meta, avifROStreamCurrent(&s), header.size, diag), AVIF_RESULT_BMFF_PARSE_FAILED);
} else if (!memcmp(header.type, "iprp", 4)) {
AVIF_CHECKERR(uniqueBoxSeen(&uniqueBoxFlags, 3, "meta", "iprp", diag), AVIF_RESULT_BMFF_PARSE_FAILED);
AVIF_CHECKRES(avifParseItemPropertiesBox(meta, rawOffset + avifROStreamOffset(&s), avifROStreamCurrent(&s), header.size, diag));
} else if (!memcmp(header.type, "iinf", 4)) {
AVIF_CHECKERR(uniqueBoxSeen(&uniqueBoxFlags, 4, "meta", "iinf", diag), AVIF_RESULT_BMFF_PARSE_FAILED);
AVIF_CHECKRES(avifParseItemInfoBox(meta, avifROStreamCurrent(&s), header.size, diag));
} else if (!memcmp(header.type, "iref", 4)) {
AVIF_CHECKERR(uniqueBoxSeen(&uniqueBoxFlags, 5, "meta", "iref", diag), AVIF_RESULT_BMFF_PARSE_FAILED);
AVIF_CHECKRES(avifParseItemReferenceBox(meta, avifROStreamCurrent(&s), header.size, diag));
}
AVIF_CHECKERR(avifROStreamSkip(&s, header.size), AVIF_RESULT_BMFF_PARSE_FAILED);
}
if (firstBox) {
// The meta box must not be empty (it must contain at least a hdlr box)
avifDiagnosticsPrintf(diag, "Box[meta] has no child boxes");
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
return AVIF_RESULT_OK;
}
static avifBool avifParseTrackHeaderBox(avifTrack * track,
const uint8_t * raw,
size_t rawLen,
uint32_t imageSizeLimit,
uint32_t imageDimensionLimit,
avifDiagnostics * diag)
{
BEGIN_STREAM(s, raw, rawLen, diag, "Box[tkhd]");
uint8_t version;
AVIF_CHECK(avifROStreamReadVersionAndFlags(&s, &version, NULL));
uint32_t ignored32, trackID;
uint64_t ignored64;
if (version == 1) {
AVIF_CHECK(avifROStreamReadU64(&s, &ignored64)); // unsigned int(64) creation_time;
AVIF_CHECK(avifROStreamReadU64(&s, &ignored64)); // unsigned int(64) modification_time;
AVIF_CHECK(avifROStreamReadU32(&s, &trackID)); // unsigned int(32) track_ID;
AVIF_CHECK(avifROStreamReadU32(&s, &ignored32)); // const unsigned int(32) reserved = 0;
AVIF_CHECK(avifROStreamReadU64(&s, &track->trackDuration)); // unsigned int(64) duration;
} else if (version == 0) {
uint32_t trackDuration;
AVIF_CHECK(avifROStreamReadU32(&s, &ignored32)); // unsigned int(32) creation_time;
AVIF_CHECK(avifROStreamReadU32(&s, &ignored32)); // unsigned int(32) modification_time;
AVIF_CHECK(avifROStreamReadU32(&s, &trackID)); // unsigned int(32) track_ID;
AVIF_CHECK(avifROStreamReadU32(&s, &ignored32)); // const unsigned int(32) reserved = 0;
AVIF_CHECK(avifROStreamReadU32(&s, &trackDuration)); // unsigned int(32) duration;
track->trackDuration = (trackDuration == AVIF_INDEFINITE_DURATION32) ? AVIF_INDEFINITE_DURATION64 : trackDuration;
} else {
// Unsupported version
avifDiagnosticsPrintf(diag, "Box[tkhd] has an unsupported version [%u]", version);
return AVIF_FALSE;
}
// Skipping the following 52 bytes here:
// ------------------------------------
// const unsigned int(32)[2] reserved = 0;
// template int(16) layer = 0;
// template int(16) alternate_group = 0;
// template int(16) volume = {if track_is_audio 0x0100 else 0};
// const unsigned int(16) reserved = 0;
// template int(32)[9] matrix= { 0x00010000,0,0,0,0x00010000,0,0,0,0x40000000 }; // unity matrix
AVIF_CHECK(avifROStreamSkip(&s, 52));
uint32_t width, height;
AVIF_CHECK(avifROStreamReadU32(&s, &width)); // unsigned int(32) width;
AVIF_CHECK(avifROStreamReadU32(&s, &height)); // unsigned int(32) height;
track->width = width >> 16;
track->height = height >> 16;
if ((track->width == 0) || (track->height == 0)) {
avifDiagnosticsPrintf(diag, "Track ID [%u] has an invalid size [%ux%u]", track->id, track->width, track->height);
return AVIF_FALSE;
}
if (avifDimensionsTooLarge(track->width, track->height, imageSizeLimit, imageDimensionLimit)) {
avifDiagnosticsPrintf(diag, "Track ID [%u] dimensions are too large [%ux%u]", track->id, track->width, track->height);
return AVIF_FALSE;
}
// TODO: support scaling based on width/height track header info?
track->id = trackID;
return AVIF_TRUE;
}
static avifBool avifParseMediaHeaderBox(avifTrack * track, const uint8_t * raw, size_t rawLen, avifDiagnostics * diag)
{
BEGIN_STREAM(s, raw, rawLen, diag, "Box[mdhd]");
uint8_t version;
AVIF_CHECK(avifROStreamReadVersionAndFlags(&s, &version, NULL));
uint32_t ignored32, mediaTimescale, mediaDuration32;
uint64_t ignored64, mediaDuration64;
if (version == 1) {
AVIF_CHECK(avifROStreamReadU64(&s, &ignored64)); // unsigned int(64) creation_time;
AVIF_CHECK(avifROStreamReadU64(&s, &ignored64)); // unsigned int(64) modification_time;
AVIF_CHECK(avifROStreamReadU32(&s, &mediaTimescale)); // unsigned int(32) timescale;
AVIF_CHECK(avifROStreamReadU64(&s, &mediaDuration64)); // unsigned int(64) duration;
track->mediaDuration = mediaDuration64;
} else if (version == 0) {
AVIF_CHECK(avifROStreamReadU32(&s, &ignored32)); // unsigned int(32) creation_time;
AVIF_CHECK(avifROStreamReadU32(&s, &ignored32)); // unsigned int(32) modification_time;
AVIF_CHECK(avifROStreamReadU32(&s, &mediaTimescale)); // unsigned int(32) timescale;
AVIF_CHECK(avifROStreamReadU32(&s, &mediaDuration32)); // unsigned int(32) duration;
track->mediaDuration = (uint64_t)mediaDuration32;
} else {
// Unsupported version
avifDiagnosticsPrintf(diag, "Box[mdhd] has an unsupported version [%u]", version);
return AVIF_FALSE;
}
track->mediaTimescale = mediaTimescale;
return AVIF_TRUE;
}
static avifResult avifParseChunkOffsetBox(avifSampleTable * sampleTable, avifBool largeOffsets, const uint8_t * raw, size_t rawLen, avifDiagnostics * diag)
{
BEGIN_STREAM(s, raw, rawLen, diag, largeOffsets ? "Box[co64]" : "Box[stco]");
AVIF_CHECKERR(avifROStreamReadAndEnforceVersion(&s, 0), AVIF_RESULT_BMFF_PARSE_FAILED);
uint32_t entryCount;
AVIF_CHECKERR(avifROStreamReadU32(&s, &entryCount), AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(32) entry_count;
for (uint32_t i = 0; i < entryCount; ++i) {
uint64_t offset;
if (largeOffsets) {
AVIF_CHECKERR(avifROStreamReadU64(&s, &offset), AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(64) chunk_offset;
} else {
uint32_t offset32;
AVIF_CHECKERR(avifROStreamReadU32(&s, &offset32), AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(32) chunk_offset;
offset = (uint64_t)offset32;
}
avifSampleTableChunk * chunk = (avifSampleTableChunk *)avifArrayPush(&sampleTable->chunks);
AVIF_CHECKERR(chunk != NULL, AVIF_RESULT_OUT_OF_MEMORY);
chunk->offset = offset;
}
return AVIF_RESULT_OK;
}
static avifResult avifParseSampleToChunkBox(avifSampleTable * sampleTable, const uint8_t * raw, size_t rawLen, avifDiagnostics * diag)
{
BEGIN_STREAM(s, raw, rawLen, diag, "Box[stsc]");
AVIF_CHECKERR(avifROStreamReadAndEnforceVersion(&s, 0), AVIF_RESULT_BMFF_PARSE_FAILED);
uint32_t entryCount;
AVIF_CHECKERR(avifROStreamReadU32(&s, &entryCount), AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(32) entry_count;
uint32_t prevFirstChunk = 0;
for (uint32_t i = 0; i < entryCount; ++i) {
avifSampleTableSampleToChunk * sampleToChunk = (avifSampleTableSampleToChunk *)avifArrayPush(&sampleTable->sampleToChunks);
AVIF_CHECKERR(sampleToChunk != NULL, AVIF_RESULT_OUT_OF_MEMORY);
AVIF_CHECKERR(avifROStreamReadU32(&s, &sampleToChunk->firstChunk), AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(32) first_chunk;
AVIF_CHECKERR(avifROStreamReadU32(&s, &sampleToChunk->samplesPerChunk), AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(32) samples_per_chunk;
AVIF_CHECKERR(avifROStreamReadU32(&s, &sampleToChunk->sampleDescriptionIndex),
AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(32) sample_description_index;
// The first_chunk fields should start with 1 and be strictly increasing.
if (i == 0) {
if (sampleToChunk->firstChunk != 1) {
avifDiagnosticsPrintf(diag, "Box[stsc] does not begin with chunk 1 [%u]", sampleToChunk->firstChunk);
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
} else {
if (sampleToChunk->firstChunk <= prevFirstChunk) {
avifDiagnosticsPrintf(diag, "Box[stsc] chunks are not strictly increasing");
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
}
prevFirstChunk = sampleToChunk->firstChunk;
}
return AVIF_RESULT_OK;
}
static avifResult avifParseSampleSizeBox(avifSampleTable * sampleTable, const uint8_t * raw, size_t rawLen, avifDiagnostics * diag)
{
BEGIN_STREAM(s, raw, rawLen, diag, "Box[stsz]");
AVIF_CHECKERR(avifROStreamReadAndEnforceVersion(&s, 0), AVIF_RESULT_BMFF_PARSE_FAILED);
uint32_t allSamplesSize, sampleCount;
AVIF_CHECKERR(avifROStreamReadU32(&s, &allSamplesSize), AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(32) sample_size;
AVIF_CHECKERR(avifROStreamReadU32(&s, &sampleCount), AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(32) sample_count;
if (allSamplesSize > 0) {
sampleTable->allSamplesSize = allSamplesSize;
} else {
for (uint32_t i = 0; i < sampleCount; ++i) {
avifSampleTableSampleSize * sampleSize = (avifSampleTableSampleSize *)avifArrayPush(&sampleTable->sampleSizes);
AVIF_CHECKERR(sampleSize != NULL, AVIF_RESULT_OUT_OF_MEMORY);
AVIF_CHECKERR(avifROStreamReadU32(&s, &sampleSize->size), AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(32) entry_size;
}
}
return AVIF_RESULT_OK;
}
static avifResult avifParseSyncSampleBox(avifSampleTable * sampleTable, const uint8_t * raw, size_t rawLen, avifDiagnostics * diag)
{
BEGIN_STREAM(s, raw, rawLen, diag, "Box[stss]");
AVIF_CHECKERR(avifROStreamReadAndEnforceVersion(&s, 0), AVIF_RESULT_BMFF_PARSE_FAILED);
uint32_t entryCount;
AVIF_CHECKERR(avifROStreamReadU32(&s, &entryCount), AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(32) entry_count;
for (uint32_t i = 0; i < entryCount; ++i) {
uint32_t sampleNumber = 0;
AVIF_CHECKERR(avifROStreamReadU32(&s, &sampleNumber), AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(32) sample_number;
avifSyncSample * syncSample = (avifSyncSample *)avifArrayPush(&sampleTable->syncSamples);
AVIF_CHECKERR(syncSample != NULL, AVIF_RESULT_OUT_OF_MEMORY);
syncSample->sampleNumber = sampleNumber;
}
return AVIF_RESULT_OK;
}
static avifResult avifParseTimeToSampleBox(avifSampleTable * sampleTable, const uint8_t * raw, size_t rawLen, avifDiagnostics * diag)
{
BEGIN_STREAM(s, raw, rawLen, diag, "Box[stts]");
AVIF_CHECKERR(avifROStreamReadAndEnforceVersion(&s, 0), AVIF_RESULT_BMFF_PARSE_FAILED);
uint32_t entryCount;
AVIF_CHECKERR(avifROStreamReadU32(&s, &entryCount), AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(32) entry_count;
for (uint32_t i = 0; i < entryCount; ++i) {
avifSampleTableTimeToSample * timeToSample = (avifSampleTableTimeToSample *)avifArrayPush(&sampleTable->timeToSamples);
AVIF_CHECKERR(timeToSample != NULL, AVIF_RESULT_OUT_OF_MEMORY);
AVIF_CHECKERR(avifROStreamReadU32(&s, &timeToSample->sampleCount), AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(32) sample_count;
AVIF_CHECKERR(avifROStreamReadU32(&s, &timeToSample->sampleDelta), AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(32) sample_delta;
}
return AVIF_RESULT_OK;
}
static avifResult avifParseSampleDescriptionBox(avifSampleTable * sampleTable,
uint64_t rawOffset,
const uint8_t * raw,
size_t rawLen,
avifDiagnostics * diag)
{
BEGIN_STREAM(s, raw, rawLen, diag, "Box[stsd]");
uint8_t version;
AVIF_CHECKERR(avifROStreamReadVersionAndFlags(&s, &version, NULL), AVIF_RESULT_BMFF_PARSE_FAILED);
// Section 8.5.2.3 of ISO/IEC 14496-12:
// version is set to zero. A version number of 1 shall be treated as a version of 0.
if (version != 0 && version != 1) {
avifDiagnosticsPrintf(diag, "Box[stsd]: Expecting box version 0 or 1, got version %u", version);
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
uint32_t entryCount;
AVIF_CHECKERR(avifROStreamReadU32(&s, &entryCount), AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(32) entry_count;
for (uint32_t i = 0; i < entryCount; ++i) {
avifBoxHeader sampleEntryHeader;
AVIF_CHECKERR(avifROStreamReadBoxHeader(&s, &sampleEntryHeader), AVIF_RESULT_BMFF_PARSE_FAILED);
avifSampleDescription * description = (avifSampleDescription *)avifArrayPush(&sampleTable->sampleDescriptions);
AVIF_CHECKERR(description != NULL, AVIF_RESULT_OUT_OF_MEMORY);
if (!avifArrayCreate(&description->properties, sizeof(avifProperty), 16)) {
avifArrayPop(&sampleTable->sampleDescriptions);
return AVIF_RESULT_OUT_OF_MEMORY;
}
memcpy(description->format, sampleEntryHeader.type, sizeof(description->format));
const size_t sampleEntryBytes = sampleEntryHeader.size;
if (avifGetCodecType(description->format) != AVIF_CODEC_TYPE_UNKNOWN) {
if (sampleEntryBytes < VISUALSAMPLEENTRY_SIZE) {
avifDiagnosticsPrintf(diag, "Not enough bytes to parse VisualSampleEntry");
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
AVIF_CHECKRES(avifParseItemPropertyContainerBox(&description->properties,
rawOffset + avifROStreamOffset(&s) + VISUALSAMPLEENTRY_SIZE,
avifROStreamCurrent(&s) + VISUALSAMPLEENTRY_SIZE,
sampleEntryBytes - VISUALSAMPLEENTRY_SIZE,
diag));
}
AVIF_CHECKERR(avifROStreamSkip(&s, sampleEntryBytes), AVIF_RESULT_BMFF_PARSE_FAILED);
}
return AVIF_RESULT_OK;
}
static avifResult avifParseSampleTableBox(avifTrack * track, uint64_t rawOffset, const uint8_t * raw, size_t rawLen, avifDiagnostics * diag)
{
if (track->sampleTable) {
// A TrackBox may only have one SampleTable
avifDiagnosticsPrintf(diag, "Duplicate Box[stbl] for a single track detected");
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
track->sampleTable = avifSampleTableCreate();
AVIF_CHECKERR(track->sampleTable != NULL, AVIF_RESULT_OUT_OF_MEMORY);
BEGIN_STREAM(s, raw, rawLen, diag, "Box[stbl]");
while (avifROStreamHasBytesLeft(&s, 1)) {
avifBoxHeader header;
AVIF_CHECKERR(avifROStreamReadBoxHeader(&s, &header), AVIF_RESULT_BMFF_PARSE_FAILED);
if (!memcmp(header.type, "stco", 4)) {
AVIF_CHECKRES(avifParseChunkOffsetBox(track->sampleTable, AVIF_FALSE, avifROStreamCurrent(&s), header.size, diag));
} else if (!memcmp(header.type, "co64", 4)) {
AVIF_CHECKRES(avifParseChunkOffsetBox(track->sampleTable, AVIF_TRUE, avifROStreamCurrent(&s), header.size, diag));
} else if (!memcmp(header.type, "stsc", 4)) {
AVIF_CHECKRES(avifParseSampleToChunkBox(track->sampleTable, avifROStreamCurrent(&s), header.size, diag));
} else if (!memcmp(header.type, "stsz", 4)) {
AVIF_CHECKRES(avifParseSampleSizeBox(track->sampleTable, avifROStreamCurrent(&s), header.size, diag));
} else if (!memcmp(header.type, "stss", 4)) {
AVIF_CHECKRES(avifParseSyncSampleBox(track->sampleTable, avifROStreamCurrent(&s), header.size, diag));
} else if (!memcmp(header.type, "stts", 4)) {
AVIF_CHECKRES(avifParseTimeToSampleBox(track->sampleTable, avifROStreamCurrent(&s), header.size, diag));
} else if (!memcmp(header.type, "stsd", 4)) {
AVIF_CHECKRES(avifParseSampleDescriptionBox(track->sampleTable,
rawOffset + avifROStreamOffset(&s),
avifROStreamCurrent(&s),
header.size,
diag));
}
AVIF_CHECKERR(avifROStreamSkip(&s, header.size), AVIF_RESULT_BMFF_PARSE_FAILED);
}
return AVIF_RESULT_OK;
}
static avifResult avifParseMediaInformationBox(avifTrack * track, uint64_t rawOffset, const uint8_t * raw, size_t rawLen, avifDiagnostics * diag)
{
BEGIN_STREAM(s, raw, rawLen, diag, "Box[minf]");
while (avifROStreamHasBytesLeft(&s, 1)) {
avifBoxHeader header;
AVIF_CHECKERR(avifROStreamReadBoxHeader(&s, &header), AVIF_RESULT_BMFF_PARSE_FAILED);
if (!memcmp(header.type, "stbl", 4)) {
AVIF_CHECKRES(avifParseSampleTableBox(track, rawOffset + avifROStreamOffset(&s), avifROStreamCurrent(&s), header.size, diag));
}
AVIF_CHECKERR(avifROStreamSkip(&s, header.size), AVIF_RESULT_BMFF_PARSE_FAILED);
}
return AVIF_RESULT_OK;
}
static avifResult avifParseMediaBox(avifTrack * track, uint64_t rawOffset, const uint8_t * raw, size_t rawLen, avifDiagnostics * diag)
{
BEGIN_STREAM(s, raw, rawLen, diag, "Box[mdia]");
while (avifROStreamHasBytesLeft(&s, 1)) {
avifBoxHeader header;
AVIF_CHECKERR(avifROStreamReadBoxHeader(&s, &header), AVIF_RESULT_BMFF_PARSE_FAILED);
if (!memcmp(header.type, "mdhd", 4)) {
AVIF_CHECKERR(avifParseMediaHeaderBox(track, avifROStreamCurrent(&s), header.size, diag), AVIF_RESULT_BMFF_PARSE_FAILED);
} else if (!memcmp(header.type, "minf", 4)) {
AVIF_CHECKRES(
avifParseMediaInformationBox(track, rawOffset + avifROStreamOffset(&s), avifROStreamCurrent(&s), header.size, diag));
}
AVIF_CHECKERR(avifROStreamSkip(&s, header.size), AVIF_RESULT_BMFF_PARSE_FAILED);
}
return AVIF_RESULT_OK;
}
static avifBool avifTrackReferenceBox(avifTrack * track, const uint8_t * raw, size_t rawLen, avifDiagnostics * diag)
{
BEGIN_STREAM(s, raw, rawLen, diag, "Box[tref]");
while (avifROStreamHasBytesLeft(&s, 1)) {
avifBoxHeader header;
AVIF_CHECK(avifROStreamReadBoxHeader(&s, &header));
if (!memcmp(header.type, "auxl", 4)) {
uint32_t toID;
AVIF_CHECK(avifROStreamReadU32(&s, &toID)); // unsigned int(32) track_IDs[];
AVIF_CHECK(avifROStreamSkip(&s, header.size - sizeof(uint32_t))); // just take the first one
track->auxForID = toID;
} else if (!memcmp(header.type, "prem", 4)) {
uint32_t byID;
AVIF_CHECK(avifROStreamReadU32(&s, &byID)); // unsigned int(32) track_IDs[];
AVIF_CHECK(avifROStreamSkip(&s, header.size - sizeof(uint32_t))); // just take the first one
track->premByID = byID;
} else {
AVIF_CHECK(avifROStreamSkip(&s, header.size));
}
}
return AVIF_TRUE;
}
static avifBool avifParseEditListBox(avifTrack * track, const uint8_t * raw, size_t rawLen, avifDiagnostics * diag)
{
BEGIN_STREAM(s, raw, rawLen, diag, "Box[elst]");
uint8_t version;
uint32_t flags;
AVIF_CHECK(avifROStreamReadVersionAndFlags(&s, &version, &flags));
if ((flags & 1) == 0) {
track->isRepeating = AVIF_FALSE;
return AVIF_TRUE;
}
track->isRepeating = AVIF_TRUE;
uint32_t entryCount;
AVIF_CHECK(avifROStreamReadU32(&s, &entryCount)); // unsigned int(32) entry_count;
if (entryCount != 1) {
avifDiagnosticsPrintf(diag, "Box[elst] contains an entry_count != 1 [%d]", entryCount);
return AVIF_FALSE;
}
if (version == 1) {
AVIF_CHECK(avifROStreamReadU64(&s, &track->segmentDuration)); // unsigned int(64) segment_duration;
} else if (version == 0) {
uint32_t segmentDuration;
AVIF_CHECK(avifROStreamReadU32(&s, &segmentDuration)); // unsigned int(32) segment_duration;
track->segmentDuration = segmentDuration;
} else {
// Unsupported version
avifDiagnosticsPrintf(diag, "Box[elst] has an unsupported version [%u]", version);
return AVIF_FALSE;
}
if (track->segmentDuration == 0) {
avifDiagnosticsPrintf(diag, "Box[elst] Invalid value for segment_duration (0).");
return AVIF_FALSE;
}
return AVIF_TRUE;
}
static avifBool avifParseEditBox(avifTrack * track, const uint8_t * raw, size_t rawLen, avifDiagnostics * diag)
{
BEGIN_STREAM(s, raw, rawLen, diag, "Box[edts]");
avifBool elstBoxSeen = AVIF_FALSE;
while (avifROStreamHasBytesLeft(&s, 1)) {
avifBoxHeader header;
AVIF_CHECK(avifROStreamReadBoxHeader(&s, &header));
if (!memcmp(header.type, "elst", 4)) {
if (elstBoxSeen) {
avifDiagnosticsPrintf(diag, "More than one [elst] Box was found.");
return AVIF_FALSE;
}
AVIF_CHECK(avifParseEditListBox(track, avifROStreamCurrent(&s), header.size, diag));
elstBoxSeen = AVIF_TRUE;
}
AVIF_CHECK(avifROStreamSkip(&s, header.size));
}
if (!elstBoxSeen) {
avifDiagnosticsPrintf(diag, "Box[edts] contains no [elst] Box.");
return AVIF_FALSE;
}
return AVIF_TRUE;
}
static avifResult avifParseTrackBox(avifDecoderData * data,
uint64_t rawOffset,
const uint8_t * raw,
size_t rawLen,
uint32_t imageSizeLimit,
uint32_t imageDimensionLimit)
{
BEGIN_STREAM(s, raw, rawLen, data->diag, "Box[trak]");
avifTrack * track = avifDecoderDataCreateTrack(data);
AVIF_CHECKERR(track != NULL, AVIF_RESULT_OUT_OF_MEMORY);
avifBool edtsBoxSeen = AVIF_FALSE;
avifBool tkhdSeen = AVIF_FALSE;
while (avifROStreamHasBytesLeft(&s, 1)) {
avifBoxHeader header;
AVIF_CHECKERR(avifROStreamReadBoxHeader(&s, &header), AVIF_RESULT_BMFF_PARSE_FAILED);
if (!memcmp(header.type, "tkhd", 4)) {
if (tkhdSeen) {
avifDiagnosticsPrintf(data->diag, "Box[trak] contains a duplicate unique box of type 'tkhd'");
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
AVIF_CHECKERR(avifParseTrackHeaderBox(track, avifROStreamCurrent(&s), header.size, imageSizeLimit, imageDimensionLimit, data->diag),
AVIF_RESULT_BMFF_PARSE_FAILED);
tkhdSeen = AVIF_TRUE;
} else if (!memcmp(header.type, "meta", 4)) {
AVIF_CHECKRES(
avifParseMetaBox(track->meta, rawOffset + avifROStreamOffset(&s), avifROStreamCurrent(&s), header.size, data->diag));
} else if (!memcmp(header.type, "mdia", 4)) {
AVIF_CHECKRES(avifParseMediaBox(track, rawOffset + avifROStreamOffset(&s), avifROStreamCurrent(&s), header.size, data->diag));
} else if (!memcmp(header.type, "tref", 4)) {
AVIF_CHECKERR(avifTrackReferenceBox(track, avifROStreamCurrent(&s), header.size, data->diag), AVIF_RESULT_BMFF_PARSE_FAILED);
} else if (!memcmp(header.type, "edts", 4)) {
if (edtsBoxSeen) {
avifDiagnosticsPrintf(data->diag, "Box[trak] contains a duplicate unique box of type 'edts'");
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
AVIF_CHECKERR(avifParseEditBox(track, avifROStreamCurrent(&s), header.size, data->diag), AVIF_RESULT_BMFF_PARSE_FAILED);
edtsBoxSeen = AVIF_TRUE;
}
AVIF_CHECKERR(avifROStreamSkip(&s, header.size), AVIF_RESULT_BMFF_PARSE_FAILED);
}
if (!tkhdSeen) {
avifDiagnosticsPrintf(data->diag, "Box[trak] does not contain a mandatory [tkhd] box");
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
if (!edtsBoxSeen) {
track->repetitionCount = AVIF_REPETITION_COUNT_UNKNOWN;
} else if (track->isRepeating) {
if (track->trackDuration == AVIF_INDEFINITE_DURATION64) {
// If isRepeating is true and the track duration is unknown/indefinite, then set the repetition count to infinite
// (Section 9.6.1 of ISO/IEC 23008-12 Part 12).
track->repetitionCount = AVIF_REPETITION_COUNT_INFINITE;
} else {
// Section 9.6.1. of ISO/IEC 23008-12 Part 12: 1, the entire edit list is repeated a sufficient number of times to
// equal the track duration.
//
// Since libavif uses repetitionCount (which is 0-based), we subtract the value by 1 to derive the number of
// repetitions.
AVIF_ASSERT_OR_RETURN(track->segmentDuration != 0);
// We specifically check for trackDuration == 0 here and not when it is actually read in order to accept files which
// inadvertently has a trackDuration of 0 without any edit lists.
if (track->trackDuration == 0) {
avifDiagnosticsPrintf(data->diag, "Invalid track duration 0.");
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
const uint64_t repetitionCount =
(track->trackDuration / track->segmentDuration) + (track->trackDuration % track->segmentDuration != 0) - 1;
if (repetitionCount > INT_MAX) {
// repetitionCount does not fit in an integer and hence it is
// likely to be a very large value. So, we just set it to
// infinite.
track->repetitionCount = AVIF_REPETITION_COUNT_INFINITE;
} else {
track->repetitionCount = (int)repetitionCount;
}
}
} else {
track->repetitionCount = 0;
}
return AVIF_RESULT_OK;
}
static avifResult avifParseMovieBox(avifDecoderData * data,
uint64_t rawOffset,
const uint8_t * raw,
size_t rawLen,
uint32_t imageSizeLimit,
uint32_t imageDimensionLimit)
{
BEGIN_STREAM(s, raw, rawLen, data->diag, "Box[moov]");
avifBool hasTrak = AVIF_FALSE;
while (avifROStreamHasBytesLeft(&s, 1)) {
avifBoxHeader header;
AVIF_CHECKERR(avifROStreamReadBoxHeader(&s, &header), AVIF_RESULT_BMFF_PARSE_FAILED);
if (!memcmp(header.type, "trak", 4)) {
AVIF_CHECKRES(
avifParseTrackBox(data, rawOffset + avifROStreamOffset(&s), avifROStreamCurrent(&s), header.size, imageSizeLimit, imageDimensionLimit));
hasTrak = AVIF_TRUE;
}
AVIF_CHECKERR(avifROStreamSkip(&s, header.size), AVIF_RESULT_BMFF_PARSE_FAILED);
}
if (!hasTrak) {
avifDiagnosticsPrintf(data->diag, "moov box does not contain any tracks");
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
return AVIF_RESULT_OK;
}
#if defined(AVIF_ENABLE_EXPERIMENTAL_METAV1)
static avifProperty * avifMetaCreateProperty(avifMeta * meta, const char * propertyType)
{
avifProperty * metaProperty = avifArrayPush(&meta->properties);
AVIF_CHECK(metaProperty);
memcpy(metaProperty->type, propertyType, 4);
return metaProperty;
}
static avifProperty * avifDecoderItemAddProperty(avifDecoderItem * item, const avifProperty * metaProperty)
{
avifProperty * itemProperty = avifArrayPush(&item->properties);
AVIF_CHECK(itemProperty);
*itemProperty = *metaProperty;
return itemProperty;
}
static avifResult avifParseMetaBoxV1(avifROStream * s, avifMeta * meta, uint64_t rawOffset, uint32_t flags, avifDiagnostics * diag)
{
meta->fromMetaV1 = AVIF_TRUE;
const avifBool hasAlpha = (flags & 0x000001) != 0; // has_alpha
const avifBool alphaIsPremultiplied = (flags & 0x000002) != 0; // alpha_is_premultiplied
const avifBool hasHdr = (flags & 0x000004) != 0; // has_hdr
const avifBool hasExplicitCicp = (flags & 0x000008) != 0; // has_explicit_cicp
const avifBool hasIcc = (flags & 0x000010) != 0; // has_icc
const avifBool hasExif = (flags & 0x000020) != 0; // has_exif
const avifBool hasXmp = (flags & 0x000040) != 0; // has_xmp
const avifBool fullRange = (flags & 0x000080) != 0; // full_range
const uint32_t pixelFormat = (flags & 0x000F00) >> 8; // pixel_format (4 bits)
const uint32_t chromaSubsampling = (flags & 0x003000) >> 12; // chroma_subsampling (2 bits)
const avifBool isHorizontallyCentered = (flags & 0x004000) != 0; // is_horizontally_centered
const avifBool isVerticallyCentered = (flags & 0x008000) != 0; // is_vertically_centered
const uint32_t orientation = (flags & 0x070000) >> 16; // orientation (3 bits)
const avifBool hasExplicitCodecTypes = (flags & 0x080000) != 0; // has_explicit_codec_types
const uint32_t dimensionSize = ((flags & 0x100000) != 0) ? 7 : 15; // dimension_size
const uint32_t codecConfigSizeSize = ((flags & 0x200000) != 0) ? 3 : 12; // codec_config_size_size
const uint32_t itemDataSizeSize = ((flags & 0x400000) != 0) ? 15 : 28; // item_data_size_size
const uint32_t metadataSizeSize = ((flags & 0x800000) != 0) ? 10 : 20; // metadata_size_size
uint8_t bitDepth;
if (pixelFormat == AVIF_METAV1_PIXEL_FORMAT_UINT8) {
bitDepth = 8;
} else if (pixelFormat == AVIF_METAV1_PIXEL_FORMAT_UINT10) {
bitDepth = 10;
} else {
AVIF_CHECKERR(pixelFormat == AVIF_METAV1_PIXEL_FORMAT_UINT12, AVIF_RESULT_BMFF_PARSE_FAILED);
bitDepth = 12;
}
uint32_t width, height;
AVIF_CHECKERR(avifROStreamReadBits(s, &width, dimensionSize), AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(dimension_size) width_minus_one;
++width;
AVIF_CHECKERR(avifROStreamReadBits(s, &height, dimensionSize), AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(dimension_size) height_minus_one;
++height;
uint32_t iccDataSize = 0;
if (hasIcc) {
AVIF_CHECKERR(avifROStreamReadBits(s, &iccDataSize, metadataSizeSize),
AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(metadata_size_size) icc_data_size_minus_one;
++iccDataSize;
}
uint8_t colorPrimaries;
uint8_t transferCharacteristics;
uint8_t matrixCoefficients;
if (hasExplicitCicp) {
AVIF_CHECKERR(avifROStreamReadBits8(s, &colorPrimaries, 8), AVIF_RESULT_BMFF_PARSE_FAILED); // bit(8) colour_primaries;
} else if (hasIcc) {
colorPrimaries = AVIF_COLOR_PRIMARIES_UNSPECIFIED; // 2
} else {
colorPrimaries = AVIF_COLOR_PRIMARIES_BT709; // 1
}
if (hasExplicitCicp) {
AVIF_CHECKERR(avifROStreamReadBits8(s, &transferCharacteristics, 8), AVIF_RESULT_BMFF_PARSE_FAILED); // bit(8) transfer_characteristics;
} else if (hasIcc) {
transferCharacteristics = AVIF_TRANSFER_CHARACTERISTICS_UNSPECIFIED; // 2
} else {
transferCharacteristics = AVIF_TRANSFER_CHARACTERISTICS_SRGB; // 13
}
if (chromaSubsampling == 0) {
// Monochrome
matrixCoefficients = AVIF_MATRIX_COEFFICIENTS_UNSPECIFIED; // 2
} else if (hasExplicitCicp) {
AVIF_CHECKERR(avifROStreamReadBits8(s, &matrixCoefficients, 8), AVIF_RESULT_BMFF_PARSE_FAILED); // bit(8) matrix_coefficients;
} else {
matrixCoefficients = AVIF_MATRIX_COEFFICIENTS_BT601; // 6
}
uint8_t infeType[4];
uint8_t codecConfigType[4];
if (hasExplicitCodecTypes) {
// bit(32) infe_type;
for (int i = 0; i < 4; ++i) {
AVIF_CHECKERR(avifROStreamReadBits8(s, &infeType[i], 8), AVIF_RESULT_BMFF_PARSE_FAILED);
}
// bit(32) codec_config_type;
for (int i = 0; i < 4; ++i) {
AVIF_CHECKERR(avifROStreamReadBits8(s, &codecConfigType[i], 8), AVIF_RESULT_BMFF_PARSE_FAILED);
}
#if defined(AVIF_CODEC_AVM)
if (!memcmp(infeType, "av02", 4) && !memcmp(codecConfigType, "av2C", 4)) {
return AVIF_RESULT_NOT_IMPLEMENTED;
}
#endif
AVIF_CHECKERR(!memcmp(infeType, "av01", 4), AVIF_RESULT_BMFF_PARSE_FAILED);
AVIF_CHECKERR(!memcmp(codecConfigType, "av1C", 4), AVIF_RESULT_BMFF_PARSE_FAILED);
} else {
memcpy(infeType, "av01", 4);
memcpy(codecConfigType, "av1C", 4);
}
uint32_t mainItemCodecConfigSize, mainItemDataSize;
AVIF_CHECKERR(avifROStreamReadBits(s, &mainItemCodecConfigSize, codecConfigSizeSize),
AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(codec_config_size_size) main_item_codec_config_size;
AVIF_CHECKERR(avifROStreamReadBits(s, &mainItemDataSize, itemDataSizeSize),
AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(item_data_size_size) main_item_data_size_minus_one;
++mainItemDataSize;
uint32_t alphaItemCodecConfigSize = 0, alphaItemDataSize = 0;
if (hasAlpha) {
AVIF_CHECKERR(avifROStreamReadBits(s, &alphaItemDataSize, itemDataSizeSize),
AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(item_data_size_size) alpha_item_data_size;
if (alphaItemDataSize != 0) {
AVIF_CHECKERR(avifROStreamReadBits(s, &alphaItemCodecConfigSize, codecConfigSizeSize),
AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(codec_config_size_size) alpha_item_codec_config_size;
}
}
if (hasHdr) {
// bit(1) has_gainmap;
// bit(1) has_clli;
// bit(1) has_mdcv;
// bit(1) has_cclv;
// bit(1) has_amve;
// bit(1) has_reve;
// bit(1) has_ndwt;
// if (has_clli)
// ContentLightLevel clli;
// if (has_mdcv)
// MasteringDisplayColourVolume mdcv;
// if (has_cclv)
// ContentColourVolume cclv;
// if (has_amve)
// AmbientViewingEnvironment amve;
// if (has_reve)
// ReferenceViewingEnvironment reve;
// if (has_ndwt)
// NominalDiffuseWhite ndwt;
// if (has_gainmap) {
// unsigned int(metadata_size_size) gainmap_metadata_size;
// unsigned int(item_data_size_size) gainmap_item_data_size;
// unsigned int(codec_config_size_size) gainmap_item_codec_config_size;
// unsigned int(dimension_size) gainmap_width_minus_one;
// unsigned int(dimension_size) gainmap_height_minus_one;
// bit(8) gainmap_matrix_coefficients;
// bit(1) gainmap_full_range;
// bit(2) gainmap_chroma_subsampling;
// bit(1) gainmap_is_horizontally_centered;
// bit(1) gainmap_is_vertically_centered;
// bit(4) gainmap_pixel_format;
// bit(1) tmap_has_clli;
// bit(1) tmap_has_mdcv;
// bit(1) tmap_has_cclv;
// bit(1) tmap_has_amve;
// bit(1) tmap_has_reve;
// bit(1) tmap_has_ndwt;
// if (tmap_has_clli)
// ContentLightLevel tmap_clli;
// if (tmap_has_mdcv)
// MasteringDisplayColourVolume tmap_mdcv;
// if (tmap_has_cclv)
// ContentColourVolume tmap_cclv;
// if (tmap_has_amve)
// AmbientViewingEnvironment tmap_amve;
// if (tmap_has_reve)
// ReferenceViewingEnvironment tmap_reve;
// if (tmap_has_ndwt)
// NominalDiffuseWhite tmap_ndwt;
// bit(1) tmap_has_icc;
// if (tmap_has_icc)
// unsigned int(metadata_size_size) tmap_icc_data_size_minus_one;
// bit(1) tmap_has_explicit_cicp;
// if (tmap_has_explicit_cicp) {
// bit(8) tmap_colour_primaries;
// bit(8) tmap_transfer_characteristics;
// bit(8) tmap_matrix_coefficients;
// bit(1) tmap_full_range;
// } else {
// tmap_colour_primaries = 1;
// tmap_transfer_characteristics = 13;
// tmap_matrix_coefficients = 6;
// tmap_full_range = 1;
// }
// }
return AVIF_RESULT_NOT_IMPLEMENTED;
}
uint32_t exifDataSize = 0;
if (hasExif) {
AVIF_CHECKERR(avifROStreamReadBits(s, &exifDataSize, metadataSizeSize),
AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(metadata_size_size) exif_data_size_minus_one;
++exifDataSize;
}
uint32_t xmpDataSize = 0;
if (hasXmp) {
AVIF_CHECKERR(avifROStreamReadBits(s, &xmpDataSize, metadataSizeSize),
AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(metadata_size_size) xmp_data_size_minus_one;
++xmpDataSize;
}
// Padding to align with whole bytes if necessary.
if (s->numUsedBitsInPartialByte) {
uint32_t padding;
AVIF_CHECKERR(avifROStreamReadBits(s, &padding, 8 - s->numUsedBitsInPartialByte), AVIF_RESULT_BMFF_PARSE_FAILED);
AVIF_CHECKERR(!padding, AVIF_RESULT_BMFF_PARSE_FAILED); // Only accept zeros as padding.
}
// Codec configs
avifCodecConfigurationBox alphaItemCodecConfig = { 0 };
if (hasAlpha) {
AVIF_CHECKERR(alphaItemDataSize > 0, AVIF_RESULT_BMFF_PARSE_FAILED);
AVIF_CHECKERR(alphaItemCodecConfigSize == 4, AVIF_RESULT_BMFF_PARSE_FAILED);
AVIF_CHECKERR(avifParseCodecConfiguration(s, &alphaItemCodecConfig, (const char *)codecConfigType, diag),
AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(8) alpha_item_codec_config[alpha_item_codec_config_size];
}
// if (has_hdr && has_gainmap && gainmap_item_codec_config_size > 0)
// unsigned int(8) gainmap_item_codec_config[gainmap_item_codec_config_size];
avifCodecConfigurationBox mainItemCodecConfig = { 0 };
AVIF_CHECKERR(mainItemCodecConfigSize == 4, AVIF_RESULT_BMFF_PARSE_FAILED);
AVIF_CHECKERR(avifParseCodecConfiguration(s, &mainItemCodecConfig, (const char *)codecConfigType, diag),
AVIF_RESULT_BMFF_PARSE_FAILED); // unsigned int(8) main_item_codec_config[main_item_codec_config_size];
// Make sure all metadata and coded chunks fit into the 'meta' box whose size is rawLen.
// There should be no missing nor unused byte.
AVIF_CHECKERR(avifROStreamRemainingBytes(s) == (uint64_t)iccDataSize + alphaItemDataSize + mainItemDataSize + exifDataSize + xmpDataSize,
AVIF_RESULT_BMFF_PARSE_FAILED);
// Create the items and properties generated by the MetaBox with version 1.
// The MetaBox with version 1 always creates 8 properties for specification easiness.
// Use FreeSpaceBoxes as no-op placeholder properties when necessary.
// There is no need to use placeholder items because item IDs do not have to
// be contiguous, whereas property indices shall be 1, 2, 3, 4, 5 etc.
meta->primaryItemID = 1;
avifDecoderItem * colorItem;
AVIF_CHECKRES(avifMetaFindOrCreateItem(meta, meta->primaryItemID, &colorItem));
memcpy(colorItem->type, infeType, 4);
colorItem->width = width;
colorItem->height = height;
colorItem->metaV1PixelFormat = chromaSubsampling == 0 ? AVIF_PIXEL_FORMAT_YUV400
: chromaSubsampling == 1 ? AVIF_PIXEL_FORMAT_YUV420
: chromaSubsampling == 2 ? AVIF_PIXEL_FORMAT_YUV422
: AVIF_PIXEL_FORMAT_YUV444;
if (colorItem->metaV1PixelFormat == AVIF_PIXEL_FORMAT_YUV422) {
// In AV1, the chroma_sample_position syntax element is not present for the YUV 4:2:2 format.
// Assume that AV1 uses the same 4:2:2 chroma sample location as HEVC and VVC (colocated).
AVIF_CHECKERR(!isHorizontallyCentered, AVIF_RESULT_BMFF_PARSE_FAILED);
// isVerticallyCentered: Ignored unless chroma_subsampling is 1.
colorItem->metaV1ChromaSamplePosition = AVIF_CHROMA_SAMPLE_POSITION_UNKNOWN;
} else if (colorItem->metaV1PixelFormat == AVIF_PIXEL_FORMAT_YUV420) {
if (isHorizontallyCentered) {
// There is no way to describe this with AV1's chroma_sample_position enum besides CSP_UNKNOWN.
// There is a proposal to assign the reserved value 3 (CSP_RESERVED) to the center chroma sample position.
colorItem->metaV1ChromaSamplePosition = AVIF_CHROMA_SAMPLE_POSITION_UNKNOWN;
} else {
colorItem->metaV1ChromaSamplePosition = isVerticallyCentered ? AVIF_CHROMA_SAMPLE_POSITION_VERTICAL
: AVIF_CHROMA_SAMPLE_POSITION_COLOCATED;
}
} else {
// isHorizontallyCentered: Ignored unless chroma_subsampling is 1 or 2.
// isVerticallyCentered: Ignored unless chroma_subsampling is 1.
colorItem->metaV1ChromaSamplePosition = AVIF_CHROMA_SAMPLE_POSITION_UNKNOWN;
}
avifDecoderItem * alphaItem = NULL;
if (hasAlpha) {
AVIF_CHECKRES(avifMetaFindOrCreateItem(meta, /*itemID=*/2, &alphaItem));
memcpy(alphaItem->type, infeType, 4);
alphaItem->width = width;
alphaItem->height = height;
alphaItem->metaV1PixelFormat = AVIF_PIXEL_FORMAT_YUV400;
alphaItem->metaV1ChromaSamplePosition = AVIF_CHROMA_SAMPLE_POSITION_UNKNOWN;
}
// Property with fixed index 1.
avifProperty * colorCodecConfigProp = avifMetaCreateProperty(meta, (const char *)codecConfigType);
AVIF_CHECKERR(colorCodecConfigProp, AVIF_RESULT_OUT_OF_MEMORY);
colorCodecConfigProp->u.av1C = mainItemCodecConfig;
AVIF_CHECKERR(avifDecoderItemAddProperty(colorItem, colorCodecConfigProp), AVIF_RESULT_OUT_OF_MEMORY);
// Property with fixed index 2.
avifProperty * ispeProp = avifMetaCreateProperty(meta, "ispe");
AVIF_CHECKERR(ispeProp, AVIF_RESULT_OUT_OF_MEMORY);
ispeProp->u.ispe.width = width;
ispeProp->u.ispe.height = height;
AVIF_CHECKERR(avifDecoderItemAddProperty(colorItem, ispeProp), AVIF_RESULT_OUT_OF_MEMORY);
// Property with fixed index 3.
avifProperty * pixiProp = avifMetaCreateProperty(meta, "pixi");
AVIF_CHECKERR(pixiProp, AVIF_RESULT_OUT_OF_MEMORY);
pixiProp->u.pixi.planeCount = chromaSubsampling == 0 ? 1 : 3;
for (uint8_t plane = 0; plane < pixiProp->u.pixi.planeCount; ++plane) {
pixiProp->u.pixi.planeDepths[plane] = bitDepth;
}
AVIF_CHECKERR(avifDecoderItemAddProperty(colorItem, pixiProp), AVIF_RESULT_OUT_OF_MEMORY);
// Property with fixed index 4.
avifProperty * colrPropNCLX = avifMetaCreateProperty(meta, "colr");
AVIF_CHECKERR(colrPropNCLX, AVIF_RESULT_OUT_OF_MEMORY);
colrPropNCLX->u.colr.hasNCLX = AVIF_TRUE; // colour_type "nclx"
colrPropNCLX->u.colr.colorPrimaries = (avifColorPrimaries)colorPrimaries;
colrPropNCLX->u.colr.transferCharacteristics = (avifTransferCharacteristics)transferCharacteristics;
colrPropNCLX->u.colr.matrixCoefficients = (avifMatrixCoefficients)matrixCoefficients;
colrPropNCLX->u.colr.range = fullRange ? AVIF_RANGE_FULL : AVIF_RANGE_LIMITED;
AVIF_CHECKERR(avifDecoderItemAddProperty(colorItem, colrPropNCLX), AVIF_RESULT_OUT_OF_MEMORY);
// Property with fixed index 5.
if (iccDataSize) {
avifProperty * colrPropICC = avifMetaCreateProperty(meta, "colr");
AVIF_CHECKERR(colrPropICC, AVIF_RESULT_OUT_OF_MEMORY);
colrPropICC->u.colr.hasICC = AVIF_TRUE; // colour_type "rICC" or "prof"
colrPropICC->u.colr.iccOffset = rawOffset + avifROStreamOffset(s);
colrPropICC->u.colr.iccSize = (size_t)iccDataSize;
AVIF_CHECKERR(avifROStreamSkip(s, colrPropICC->u.colr.iccSize), AVIF_RESULT_BMFF_PARSE_FAILED);
AVIF_CHECKERR(avifDecoderItemAddProperty(colorItem, colrPropICC), AVIF_RESULT_OUT_OF_MEMORY);
} else {
AVIF_CHECKERR(avifMetaCreateProperty(meta, "skip"), AVIF_RESULT_OUT_OF_MEMORY); // Placeholder.
}
// if (has_hdr && has_gainmap && tmap_has_icc)
// unsigned int(8) tmap_icc_data[tmap_icc_data_size_minus_one + 1];
// if (has_hdr && has_gainmap && gainmap_metadata_size > 0)
// unsigned int(8) gainmap_metadata[gainmap_metadata_size];
if (hasAlpha) {
// Property with fixed index 6.
avifProperty * alphaCodecConfigProp = avifMetaCreateProperty(meta, (const char *)codecConfigType);
AVIF_CHECKERR(alphaCodecConfigProp, AVIF_RESULT_OUT_OF_MEMORY);
alphaCodecConfigProp->u.av1C = alphaItemCodecConfig;
AVIF_CHECKERR(avifDecoderItemAddProperty(alphaItem, alphaCodecConfigProp), AVIF_RESULT_OUT_OF_MEMORY);
// Property with fixed index 7.
alphaItem->auxForID = colorItem->id;
colorItem->premByID = alphaIsPremultiplied;
avifProperty * alphaAuxProp = avifMetaCreateProperty(meta, "auxC");
AVIF_CHECKERR(alphaAuxProp, AVIF_RESULT_OUT_OF_MEMORY);
strcpy(alphaAuxProp->u.auxC.auxType, AVIF_URN_ALPHA0);
AVIF_CHECKERR(avifDecoderItemAddProperty(alphaItem, alphaAuxProp), AVIF_RESULT_OUT_OF_MEMORY);
// Property with fixed index 2 (reused).
AVIF_CHECKERR(avifDecoderItemAddProperty(alphaItem, ispeProp), AVIF_RESULT_OUT_OF_MEMORY);
// Property with fixed index 8.
avifProperty * alphaPixiProp = avifMetaCreateProperty(meta, "pixi");
AVIF_CHECKERR(alphaPixiProp, AVIF_RESULT_OUT_OF_MEMORY);
memcpy(alphaPixiProp->type, "pixi", 4);
alphaPixiProp->u.pixi.planeCount = 1;
alphaPixiProp->u.pixi.planeDepths[0] = bitDepth;
AVIF_CHECKERR(avifDecoderItemAddProperty(alphaItem, alphaPixiProp), AVIF_RESULT_OUT_OF_MEMORY);
} else {
// Placeholders 6, 7 and 8.
AVIF_CHECKERR(avifMetaCreateProperty(meta, "skip"), AVIF_RESULT_OUT_OF_MEMORY);
AVIF_CHECKERR(avifMetaCreateProperty(meta, "skip"), AVIF_RESULT_OUT_OF_MEMORY);
AVIF_CHECKERR(avifMetaCreateProperty(meta, "skip"), AVIF_RESULT_OUT_OF_MEMORY);
}
// Same behavior as avifImageExtractExifOrientationToIrotImir() for orientation+1.
if (orientation == 2 || orientation == 4 || orientation == 5 || orientation == 6 || orientation == 7) {
// Property with fixed index 9.
avifProperty * irotProp = avifMetaCreateProperty(meta, "irot");
AVIF_CHECKERR(irotProp, AVIF_RESULT_OUT_OF_MEMORY);
irotProp->u.irot.angle = orientation == 2 ? 2 : (orientation == 4 || orientation == 7) ? 1 : 3;
AVIF_CHECKERR(avifDecoderItemAddProperty(colorItem, irotProp), AVIF_RESULT_OUT_OF_MEMORY);
} else {
AVIF_CHECKERR(avifMetaCreateProperty(meta, "skip"), AVIF_RESULT_OUT_OF_MEMORY); // Placeholder.
}
if (orientation == 1 || orientation == 3 || orientation == 4 || orientation == 6) {
// Property with fixed index 10.
avifProperty * imirProp = avifMetaCreateProperty(meta, "imir");
AVIF_CHECKERR(imirProp, AVIF_RESULT_OUT_OF_MEMORY);
imirProp->u.imir.axis = orientation == 1 ? 1 : 0;
AVIF_CHECKERR(avifDecoderItemAddProperty(colorItem, imirProp), AVIF_RESULT_OUT_OF_MEMORY);
} else {
AVIF_CHECKERR(avifMetaCreateProperty(meta, "skip"), AVIF_RESULT_OUT_OF_MEMORY); // Placeholder.
}
// HDR placeholders (unnecessary but added for specification matching).
for (int i = 11; i <= 29; ++i) {
AVIF_CHECKERR(avifMetaCreateProperty(meta, "skip"), AVIF_RESULT_OUT_OF_MEMORY);
}
// Extents.
if (hasAlpha) {
avifExtent * alphaExtent = (avifExtent *)avifArrayPush(&alphaItem->extents);
AVIF_CHECKERR(alphaExtent, AVIF_RESULT_OUT_OF_MEMORY);
alphaExtent->offset = rawOffset + avifROStreamOffset(s);
alphaExtent->size = (size_t)alphaItemDataSize;
AVIF_CHECKERR(avifROStreamSkip(s, alphaExtent->size), AVIF_RESULT_BMFF_PARSE_FAILED);
alphaItem->size = alphaExtent->size;
}
// if (has_hdr && has_gainmap && gainmap_item_data_size > 0)
// unsigned int(8) gainmap_item_data[gainmap_item_data_size];
avifExtent * colorExtent = (avifExtent *)avifArrayPush(&colorItem->extents);
AVIF_CHECKERR(colorExtent, AVIF_RESULT_OUT_OF_MEMORY);
colorExtent->offset = rawOffset + avifROStreamOffset(s);
colorExtent->size = (size_t)mainItemDataSize;
AVIF_CHECKERR(avifROStreamSkip(s, colorExtent->size), AVIF_RESULT_BMFF_PARSE_FAILED);
colorItem->size = colorExtent->size;
if (hasExif) {
avifDecoderItem * exifItem;
AVIF_CHECKRES(avifMetaFindOrCreateItem(meta, /*itemID=*/3, &exifItem));
memcpy(exifItem->type, "Exif", 4);
exifItem->descForID = colorItem->id;
colorItem->premByID = alphaIsPremultiplied;
avifExtent * exifExtent = (avifExtent *)avifArrayPush(&exifItem->extents);
AVIF_CHECKERR(exifExtent, AVIF_RESULT_OUT_OF_MEMORY);
exifExtent->offset = rawOffset + avifROStreamOffset(s);
exifExtent->size = (size_t)exifDataSize; // Does not include unsigned int(32) exif_tiff_header_offset;
AVIF_CHECKERR(avifROStreamSkip(s, exifExtent->size), AVIF_RESULT_BMFF_PARSE_FAILED);
exifItem->size = exifExtent->size;
}
if (hasXmp) {
avifDecoderItem * xmpItem;
AVIF_CHECKRES(avifMetaFindOrCreateItem(meta, /*itemID=*/4, &xmpItem));
memcpy(xmpItem->type, "mime", 4);
memcpy(xmpItem->contentType.contentType, AVIF_CONTENT_TYPE_XMP, sizeof(AVIF_CONTENT_TYPE_XMP));
xmpItem->descForID = colorItem->id;
colorItem->premByID = alphaIsPremultiplied;
avifExtent * xmpExtent = (avifExtent *)avifArrayPush(&xmpItem->extents);
AVIF_CHECKERR(xmpExtent, AVIF_RESULT_OUT_OF_MEMORY);
xmpExtent->offset = rawOffset + avifROStreamOffset(s);
xmpExtent->size = (size_t)xmpDataSize;
AVIF_CHECKERR(avifROStreamSkip(s, xmpExtent->size), AVIF_RESULT_BMFF_PARSE_FAILED);
xmpItem->size = xmpExtent->size;
}
return AVIF_RESULT_OK;
}
#endif // AVIF_ENABLE_EXPERIMENTAL_METAV1
static avifBool avifParseFileTypeBox(avifFileType * ftyp, const uint8_t * raw, size_t rawLen, avifDiagnostics * diag)
{
BEGIN_STREAM(s, raw, rawLen, diag, "Box[ftyp]");
AVIF_CHECK(avifROStreamRead(&s, ftyp->majorBrand, 4));
AVIF_CHECK(avifROStreamReadU32(&s, &ftyp->minorVersion));
size_t compatibleBrandsBytes = avifROStreamRemainingBytes(&s);
if ((compatibleBrandsBytes % 4) != 0) {
avifDiagnosticsPrintf(diag, "Box[ftyp] contains a compatible brands section that isn't divisible by 4 [%zu]", compatibleBrandsBytes);
return AVIF_FALSE;
}
ftyp->compatibleBrands = avifROStreamCurrent(&s);
AVIF_CHECK(avifROStreamSkip(&s, compatibleBrandsBytes));
ftyp->compatibleBrandsCount = (int)compatibleBrandsBytes / 4;
return AVIF_TRUE;
}
static avifBool avifFileTypeHasBrand(avifFileType * ftyp, const char * brand);
static avifBool avifFileTypeIsCompatible(avifFileType * ftyp);
static avifResult avifParse(avifDecoder * decoder)
{
// Note: this top-level function is the only avifParse*() function that returns avifResult instead of avifBool.
// Be sure to use AVIF_CHECKERR() in this function with an explicit error result instead of simply using AVIF_CHECK().
avifResult readResult;
uint64_t parseOffset = 0;
avifDecoderData * data = decoder->data;
avifBool ftypSeen = AVIF_FALSE;
avifBool metaV0Seen = AVIF_FALSE;
avifBool moovSeen = AVIF_FALSE;
avifBool needsMetaV0 = AVIF_FALSE;
avifBool needsMoov = AVIF_FALSE;
#if defined(AVIF_ENABLE_EXPERIMENTAL_METAV1)
avifBool metaV1Seen = AVIF_FALSE;
avifBool needsMetaV1 = AVIF_FALSE;
#endif
for (;;) {
// Read just enough to get the next box header (a max of 32 bytes)
avifROData headerContents;
if ((decoder->io->sizeHint > 0) && (parseOffset > decoder->io->sizeHint)) {
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
readResult = decoder->io->read(decoder->io, 0, parseOffset, 32, &headerContents);
if (readResult != AVIF_RESULT_OK) {
return readResult;
}
if (!headerContents.size) {
// If we got AVIF_RESULT_OK from the reader but received 0 bytes,
// we've reached the end of the file with no errors. Hooray!
break;
}
// Parse the header, and find out how many bytes it actually was
BEGIN_STREAM(headerStream, headerContents.data, headerContents.size, &decoder->diag, "File-level box header");
avifBoxHeader header;
AVIF_CHECKERR(avifROStreamReadBoxHeaderPartial(&headerStream, &header, /*topLevel=*/AVIF_TRUE), AVIF_RESULT_BMFF_PARSE_FAILED);
parseOffset += headerStream.offset;
AVIF_ASSERT_OR_RETURN(decoder->io->sizeHint == 0 || parseOffset <= decoder->io->sizeHint);
// Try to get the remainder of the box, if necessary
uint64_t boxOffset = 0;
avifROData boxContents = AVIF_DATA_EMPTY;
// TODO: reorg this code to only do these memcmps once each
if (!memcmp(header.type, "ftyp", 4) || !memcmp(header.type, "meta", 4) || !memcmp(header.type, "moov", 4)) {
boxOffset = parseOffset;
size_t sizeToRead;
if (header.isSizeZeroBox) {
// The box body goes till the end of the file.
if (decoder->io->sizeHint != 0 && decoder->io->sizeHint - parseOffset < SIZE_MAX) {
sizeToRead = decoder->io->sizeHint - parseOffset;
} else {
sizeToRead = SIZE_MAX; // This will get truncated. See the documentation of avifIOReadFunc.
}
} else {
sizeToRead = header.size;
}
readResult = decoder->io->read(decoder->io, 0, parseOffset, sizeToRead, &boxContents);
if (readResult != AVIF_RESULT_OK) {
return readResult;
}
if (header.isSizeZeroBox) {
header.size = boxContents.size;
} else if (boxContents.size != header.size) {
// A truncated box, bail out
return AVIF_RESULT_TRUNCATED_DATA;
}
} else if (header.isSizeZeroBox) {
// An unknown top level box with size 0 was found. If we reach here it means we haven't completed parsing successfully
// since there are no further boxes left.
return AVIF_RESULT_BMFF_PARSE_FAILED;
} else if (header.size > (UINT64_MAX - parseOffset)) {
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
parseOffset += header.size;
if (!memcmp(header.type, "ftyp", 4)) {
AVIF_CHECKERR(!ftypSeen, AVIF_RESULT_BMFF_PARSE_FAILED);
avifFileType ftyp;
AVIF_CHECKERR(avifParseFileTypeBox(&ftyp, boxContents.data, boxContents.size, data->diag), AVIF_RESULT_BMFF_PARSE_FAILED);
if (!avifFileTypeIsCompatible(&ftyp)) {
return AVIF_RESULT_INVALID_FTYP;
}
ftypSeen = AVIF_TRUE;
memcpy(data->majorBrand, ftyp.majorBrand, 4); // Remember the major brand for future AVIF_DECODER_SOURCE_AUTO decisions
needsMetaV0 = avifFileTypeHasBrand(&ftyp, "avif");
needsMoov = avifFileTypeHasBrand(&ftyp, "avis");
#if defined(AVIF_ENABLE_EXPERIMENTAL_METAV1)
needsMetaV1 = avifFileTypeHasBrand(&ftyp, "mif3");
if (needsMetaV1 && (needsMetaV0 || needsMoov)) {
return AVIF_RESULT_INVALID_FTYP;
}
#endif // AVIF_ENABLE_EXPERIMENTAL_METAV1
} else if (!memcmp(header.type, "meta", 4)) {
AVIF_CHECKERR(!metaV0Seen, AVIF_RESULT_BMFF_PARSE_FAILED);
#if defined(AVIF_ENABLE_EXPERIMENTAL_METAV1)
AVIF_CHECKERR(!metaV1Seen, AVIF_RESULT_BMFF_PARSE_FAILED);
#endif
AVIF_CHECKRES(avifParseMetaBox(data->meta, boxOffset, boxContents.data, boxContents.size, data->diag));
#if defined(AVIF_ENABLE_EXPERIMENTAL_METAV1)
if (data->meta->fromMetaV1) {
metaV1Seen = AVIF_TRUE;
} else {
metaV0Seen = AVIF_TRUE;
}
#else
metaV0Seen = AVIF_TRUE;
#endif
} else if (!memcmp(header.type, "moov", 4)) {
AVIF_CHECKERR(!moovSeen, AVIF_RESULT_BMFF_PARSE_FAILED);
AVIF_CHECKRES(
avifParseMovieBox(data, boxOffset, boxContents.data, boxContents.size, decoder->imageSizeLimit, decoder->imageDimensionLimit));
moovSeen = AVIF_TRUE;
decoder->imageSequenceTrackPresent = AVIF_TRUE;
}
#if defined(AVIF_ENABLE_EXPERIMENTAL_METAV1)
if (ftypSeen && !needsMetaV1 && metaV1Seen) {
// The 'meta' box with version 1 should be ignored if there is no 'mif3' brand, but libavif allows reading them in any order.
return AVIF_RESULT_NOT_IMPLEMENTED; // TODO(yguyon): Implement
}
#endif // AVIF_ENABLE_EXPERIMENTAL_METAV1
// See if there is enough information to consider Parse() a success and early-out:
// * If the brand 'avif' is present, require a meta box with version 0
// * If the brand 'avis' is present, require a moov box
// * If AVIF_ENABLE_EXPERIMENTAL_METAV1 is defined and the brand 'mif3' is present, require a meta box with version 1
#if defined(AVIF_ENABLE_EXPERIMENTAL_METAV1)
if (ftypSeen && (!needsMetaV0 || metaV0Seen) && (!needsMoov || moovSeen) && (!needsMetaV1 || metaV1Seen)) {
#else
if (ftypSeen && (!needsMetaV0 || metaV0Seen) && (!needsMoov || moovSeen)) {
#endif
return AVIF_RESULT_OK;
}
}
if (!ftypSeen) {
return AVIF_RESULT_INVALID_FTYP;
}
if ((needsMetaV0 && !metaV0Seen) || (needsMoov && !moovSeen)) {
return AVIF_RESULT_TRUNCATED_DATA;
}
#if defined(AVIF_ENABLE_EXPERIMENTAL_METAV1)
if (needsMetaV1 && !metaV1Seen) {
return AVIF_RESULT_TRUNCATED_DATA;
}
#endif
return AVIF_RESULT_OK;
}
// ---------------------------------------------------------------------------
static avifBool avifFileTypeHasBrand(avifFileType * ftyp, const char * brand)
{
if (!memcmp(ftyp->majorBrand, brand, 4)) {
return AVIF_TRUE;
}
for (int compatibleBrandIndex = 0; compatibleBrandIndex < ftyp->compatibleBrandsCount; ++compatibleBrandIndex) {
const uint8_t * compatibleBrand = &ftyp->compatibleBrands[4 * compatibleBrandIndex];
if (!memcmp(compatibleBrand, brand, 4)) {
return AVIF_TRUE;
}
}
return AVIF_FALSE;
}
static avifBool avifFileTypeIsCompatible(avifFileType * ftyp)
{
return avifFileTypeHasBrand(ftyp, "avif") || avifFileTypeHasBrand(ftyp, "avis")
#if defined(AVIF_ENABLE_EXPERIMENTAL_METAV1)
|| avifFileTypeHasBrand(ftyp, "mif3")
#endif // AVIF_ENABLE_EXPERIMENTAL_METAV1
;
}
avifBool avifPeekCompatibleFileType(const avifROData * input)
{
BEGIN_STREAM(s, input->data, input->size, NULL, NULL);
avifBoxHeader header;
if (!avifROStreamReadBoxHeaderPartial(&s, &header, /*topLevel=*/AVIF_TRUE) || memcmp(header.type, "ftyp", 4)) {
return AVIF_FALSE;
}
if (header.isSizeZeroBox) {
// The ftyp box goes on till the end of the file. Either there is no brand requiring anything in the file but a
// FileTypebox (so not AVIF), or it is invalid.
return AVIF_FALSE;
}
AVIF_CHECK(avifROStreamHasBytesLeft(&s, header.size));
avifFileType ftyp;
memset(&ftyp, 0, sizeof(avifFileType));
avifBool parsed = avifParseFileTypeBox(&ftyp, avifROStreamCurrent(&s), header.size, NULL);
if (!parsed) {
return AVIF_FALSE;
}
return avifFileTypeIsCompatible(&ftyp);
}
// ---------------------------------------------------------------------------
avifDecoder * avifDecoderCreate(void)
{
avifDecoder * decoder = (avifDecoder *)avifAlloc(sizeof(avifDecoder));
if (decoder == NULL) {
return NULL;
}
memset(decoder, 0, sizeof(avifDecoder));
decoder->maxThreads = 1;
decoder->imageSizeLimit = AVIF_DEFAULT_IMAGE_SIZE_LIMIT;
decoder->imageDimensionLimit = AVIF_DEFAULT_IMAGE_DIMENSION_LIMIT;
decoder->imageCountLimit = AVIF_DEFAULT_IMAGE_COUNT_LIMIT;
decoder->strictFlags = AVIF_STRICT_ENABLED;
return decoder;
}
static void avifDecoderCleanup(avifDecoder * decoder)
{
if (decoder->data) {
avifDecoderDataDestroy(decoder->data);
decoder->data = NULL;
}
if (decoder->image) {
avifImageDestroy(decoder->image);
decoder->image = NULL;
}
avifDiagnosticsClearError(&decoder->diag);
}
void avifDecoderDestroy(avifDecoder * decoder)
{
avifDecoderCleanup(decoder);
avifIODestroy(decoder->io);
avifFree(decoder);
}
avifResult avifDecoderSetSource(avifDecoder * decoder, avifDecoderSource source)
{
decoder->requestedSource = source;
return avifDecoderReset(decoder);
}
void avifDecoderSetIO(avifDecoder * decoder, avifIO * io)
{
avifIODestroy(decoder->io);
decoder->io = io;
}
avifResult avifDecoderSetIOMemory(avifDecoder * decoder, const uint8_t * data, size_t size)
{
avifIO * io = avifIOCreateMemoryReader(data, size);
AVIF_CHECKERR(io != NULL, AVIF_RESULT_OUT_OF_MEMORY);
avifDecoderSetIO(decoder, io);
return AVIF_RESULT_OK;
}
avifResult avifDecoderSetIOFile(avifDecoder * decoder, const char * filename)
{
avifIO * io = avifIOCreateFileReader(filename);
if (!io) {
return AVIF_RESULT_IO_ERROR;
}
avifDecoderSetIO(decoder, io);
return AVIF_RESULT_OK;
}
// 0-byte extents are ignored/overwritten during the merge, as they are the signal from helper
// functions that no extent was necessary for this given sample. If both provided extents are
// >0 bytes, this will set dst to be an extent that bounds both supplied extents.
static avifResult avifExtentMerge(avifExtent * dst, const avifExtent * src)
{
if (!dst->size) {
*dst = *src;
return AVIF_RESULT_OK;
}
if (!src->size) {
return AVIF_RESULT_OK;
}
const uint64_t minExtent1 = dst->offset;
const uint64_t maxExtent1 = dst->offset + dst->size;
const uint64_t minExtent2 = src->offset;
const uint64_t maxExtent2 = src->offset + src->size;
dst->offset = AVIF_MIN(minExtent1, minExtent2);
const uint64_t extentLength = AVIF_MAX(maxExtent1, maxExtent2) - dst->offset;
if (extentLength > SIZE_MAX) {
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
dst->size = (size_t)extentLength;
return AVIF_RESULT_OK;
}
avifResult avifDecoderNthImageMaxExtent(const avifDecoder * decoder, uint32_t frameIndex, avifExtent * outExtent)
{
if (!decoder->data) {
// Nothing has been parsed yet
return AVIF_RESULT_NO_CONTENT;
}
memset(outExtent, 0, sizeof(avifExtent));
uint32_t startFrameIndex = avifDecoderNearestKeyframe(decoder, frameIndex);
uint32_t endFrameIndex = frameIndex;
for (uint32_t currentFrameIndex = startFrameIndex; currentFrameIndex <= endFrameIndex; ++currentFrameIndex) {
for (unsigned int tileIndex = 0; tileIndex < decoder->data->tiles.count; ++tileIndex) {
avifTile * tile = &decoder->data->tiles.tile[tileIndex];
if (currentFrameIndex >= tile->input->samples.count) {
return AVIF_RESULT_NO_IMAGES_REMAINING;
}
avifDecodeSample * sample = &tile->input->samples.sample[currentFrameIndex];
avifExtent sampleExtent;
if (sample->itemID) {
// The data comes from an item. Let avifDecoderItemMaxExtent() do the heavy lifting.
avifDecoderItem * item;
AVIF_CHECKRES(avifMetaFindOrCreateItem(decoder->data->meta, sample->itemID, &item));
avifResult maxExtentResult = avifDecoderItemMaxExtent(item, sample, &sampleExtent);
if (maxExtentResult != AVIF_RESULT_OK) {
return maxExtentResult;
}
} else {
// The data likely comes from a sample table. Use the sample position directly.
sampleExtent.offset = sample->offset;
sampleExtent.size = sample->size;
}
if (sampleExtent.size > UINT64_MAX - sampleExtent.offset) {
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
avifResult extentMergeResult = avifExtentMerge(outExtent, &sampleExtent);
if (extentMergeResult != AVIF_RESULT_OK) {
return extentMergeResult;
}
}
}
return AVIF_RESULT_OK;
}
static avifResult avifDecoderPrepareSample(avifDecoder * decoder, avifDecodeSample * sample, size_t partialByteCount)
{
if (!sample->data.size || sample->partialData) {
// This sample hasn't been read from IO or had its extents fully merged yet.
size_t bytesToRead = sample->size;
if (partialByteCount && (bytesToRead > partialByteCount)) {
bytesToRead = partialByteCount;
}
if (sample->itemID) {
// The data comes from an item. Let avifDecoderItemRead() do the heavy lifting.
avifDecoderItem * item;
AVIF_CHECKRES(avifMetaFindOrCreateItem(decoder->data->meta, sample->itemID, &item));
avifROData itemContents;
if (sample->offset > SIZE_MAX) {
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
size_t offset = (size_t)sample->offset;
avifResult readResult = avifDecoderItemRead(item, decoder->io, &itemContents, offset, bytesToRead, &decoder->diag);
if (readResult != AVIF_RESULT_OK) {
return readResult;
}
// avifDecoderItemRead is guaranteed to already be persisted by either the underlying IO
// or by mergedExtents; just reuse the buffer here.
sample->data = itemContents;
sample->ownsData = AVIF_FALSE;
sample->partialData = item->partialMergedExtents;
} else {
// The data likely comes from a sample table. Pull the sample and make a copy if necessary.
avifROData sampleContents;
if ((decoder->io->sizeHint > 0) && (sample->offset > decoder->io->sizeHint)) {
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
avifResult readResult = decoder->io->read(decoder->io, 0, sample->offset, bytesToRead, &sampleContents);
if (readResult != AVIF_RESULT_OK) {
return readResult;
}
if (sampleContents.size != bytesToRead) {
return AVIF_RESULT_TRUNCATED_DATA;
}
sample->ownsData = !decoder->io->persistent;
sample->partialData = (bytesToRead != sample->size);
if (decoder->io->persistent) {
sample->data = sampleContents;
} else {
AVIF_CHECKRES(avifRWDataSet((avifRWData *)&sample->data, sampleContents.data, sampleContents.size));
}
}
}
return AVIF_RESULT_OK;
}
// Returns AVIF_TRUE if the item should be skipped. Items should be skipped for one of the following reasons:
// * Size is 0.
// * Has an essential property that isn't supported by libavif.
// * Item is not a single image or a grid.
// * Item is a thumbnail.
static avifBool avifDecoderItemShouldBeSkipped(const avifDecoderItem * item)
{
return !item->size || item->hasUnsupportedEssentialProperty ||
(avifGetCodecType(item->type) == AVIF_CODEC_TYPE_UNKNOWN && memcmp(item->type, "grid", 4)) || item->thumbnailForID != 0;
}
avifResult avifDecoderParse(avifDecoder * decoder)
{
avifDiagnosticsClearError(&decoder->diag);
// An imageSizeLimit greater than AVIF_DEFAULT_IMAGE_SIZE_LIMIT and the special value of 0 to
// disable the limit are not yet implemented.
if ((decoder->imageSizeLimit > AVIF_DEFAULT_IMAGE_SIZE_LIMIT) || (decoder->imageSizeLimit == 0)) {
return AVIF_RESULT_NOT_IMPLEMENTED;
}
if (!decoder->io || !decoder->io->read) {
return AVIF_RESULT_IO_NOT_SET;
}
// Cleanup anything lingering in the decoder
avifDecoderCleanup(decoder);
// -----------------------------------------------------------------------
// Parse BMFF boxes
decoder->data = avifDecoderDataCreate();
AVIF_CHECKERR(decoder->data != NULL, AVIF_RESULT_OUT_OF_MEMORY);
decoder->data->diag = &decoder->diag;
AVIF_CHECKRES(avifParse(decoder));
// Walk the decoded items (if any) and harvest ispe
avifDecoderData * data = decoder->data;
for (uint32_t itemIndex = 0; itemIndex < data->meta->items.count; ++itemIndex) {
avifDecoderItem * item = data->meta->items.item[itemIndex];
if (avifDecoderItemShouldBeSkipped(item)) {
continue;
}
const avifProperty * ispeProp = avifPropertyArrayFind(&item->properties, "ispe");
if (ispeProp) {
item->width = ispeProp->u.ispe.width;
item->height = ispeProp->u.ispe.height;
if ((item->width == 0) || (item->height == 0)) {
avifDiagnosticsPrintf(data->diag, "Item ID [%u] has an invalid size [%ux%u]", item->id, item->width, item->height);
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
if (avifDimensionsTooLarge(item->width, item->height, decoder->imageSizeLimit, decoder->imageDimensionLimit)) {
avifDiagnosticsPrintf(data->diag, "Item ID [%u] dimensions are too large [%ux%u]", item->id, item->width, item->height);
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
} else {
const avifProperty * auxCProp = avifPropertyArrayFind(&item->properties, "auxC");
if (auxCProp && isAlphaURN(auxCProp->u.auxC.auxType)) {
if (decoder->strictFlags & AVIF_STRICT_ALPHA_ISPE_REQUIRED) {
avifDiagnosticsPrintf(data->diag,
"[Strict] Alpha auxiliary image item ID [%u] is missing a mandatory ispe property",
item->id);
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
} else {
avifDiagnosticsPrintf(data->diag, "Item ID [%u] is missing a mandatory ispe property", item->id);
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
}
}
return avifDecoderReset(decoder);
}
static avifResult avifCodecCreateInternal(avifCodecChoice choice, const avifTile * tile, avifDiagnostics * diag, avifCodec ** codec)
{
#if defined(AVIF_CODEC_AVM)
// AVIF_CODEC_CHOICE_AUTO leads to AVIF_CODEC_TYPE_AV1 by default. Reroute correctly.
if (choice == AVIF_CODEC_CHOICE_AUTO && tile->codecType == AVIF_CODEC_TYPE_AV2) {
choice = AVIF_CODEC_CHOICE_AVM;
}
#endif
const avifCodecType codecTypeFromChoice = avifCodecTypeFromChoice(choice, AVIF_CODEC_FLAG_CAN_DECODE);
if (codecTypeFromChoice == AVIF_CODEC_TYPE_UNKNOWN) {
avifDiagnosticsPrintf(diag,
"Tile type is %s but there is no compatible codec available to decode it",
avifGetConfigurationPropertyName(tile->codecType));
return AVIF_RESULT_NO_CODEC_AVAILABLE;
} else if (choice != AVIF_CODEC_CHOICE_AUTO && codecTypeFromChoice != tile->codecType) {
avifDiagnosticsPrintf(diag,
"Tile type is %s but incompatible %s codec was explicitly set as decoding implementation",
avifGetConfigurationPropertyName(tile->codecType),
avifCodecName(choice, AVIF_CODEC_FLAG_CAN_DECODE));
return AVIF_RESULT_DECODE_COLOR_FAILED;
}
AVIF_CHECKRES(avifCodecCreate(choice, AVIF_CODEC_FLAG_CAN_DECODE, codec));
AVIF_CHECKERR(*codec, AVIF_RESULT_OUT_OF_MEMORY);
(*codec)->diag = diag;
(*codec)->operatingPoint = tile->operatingPoint;
(*codec)->allLayers = tile->input->allLayers;
return AVIF_RESULT_OK;
}
static avifBool avifTilesCanBeDecodedWithSameCodecInstance(avifDecoderData * data)
{
int32_t numImageBuffers = 0, numStolenImageBuffers = 0;
for (int c = 0; c < AVIF_ITEM_CATEGORY_COUNT; ++c) {
if (data->tileInfos[c].tileCount > 0) {
++numImageBuffers;
}
#if defined(AVIF_ENABLE_EXPERIMENTAL_SAMPLE_TRANSFORM)
// The sample operations require multiple buffers for compositing so no plane is stolen
// when there is a 'sato' Sample Transform derived image item.
if (c >= AVIF_SAMPLE_TRANSFORM_MIN_CATEGORY && c <= AVIF_SAMPLE_TRANSFORM_MAX_CATEGORY && data->tileInfos[c].tileCount > 0) {
continue;
}
#endif
if (data->tileInfos[c].tileCount == 1) {
++numStolenImageBuffers;
}
}
if (numStolenImageBuffers > 0 && numImageBuffers > 1) {
// Single tile image with single tile alpha plane or gain map. In this case each tile needs its own decoder since the planes will be
// "stolen". Stealing either the color or the alpha plane (or gain map) will invalidate the other ones when decode is called the second
// (or third) time.
return AVIF_FALSE;
}
const uint8_t firstTileOperatingPoint = data->tiles.tile[0].operatingPoint;
const avifBool firstTileAllLayers = data->tiles.tile[0].input->allLayers;
for (unsigned int i = 1; i < data->tiles.count; ++i) {
const avifTile * tile = &data->tiles.tile[i];
if (tile->operatingPoint != firstTileOperatingPoint || tile->input->allLayers != firstTileAllLayers) {
return AVIF_FALSE;
}
// avifDecoderItemValidateProperties() verified during avifDecoderParse() that all tiles
// share the same coding format so no need to check for codecType equality here.
}
return AVIF_TRUE;
}
static avifResult avifDecoderCreateCodecs(avifDecoder * decoder)
{
avifDecoderData * data = decoder->data;
avifDecoderDataResetCodec(data);
if (data->source == AVIF_DECODER_SOURCE_TRACKS) {
// In this case, we will use at most two codec instances (one for the color planes and one for the alpha plane).
// Gain maps are not supported.
AVIF_CHECKRES(avifCodecCreateInternal(decoder->codecChoice, &decoder->data->tiles.tile[0], &decoder->diag, &data->codec));
data->tiles.tile[0].codec = data->codec;
if (data->tiles.count > 1) {
AVIF_CHECKRES(avifCodecCreateInternal(decoder->codecChoice, &decoder->data->tiles.tile[1], &decoder->diag, &data->codecAlpha));
data->tiles.tile[1].codec = data->codecAlpha;
}
} else {
// In this case, we will use one codec instance when there is only one tile or when all of the following conditions are
// met:
// - The image must have exactly one layer (i.e.) decoder->imageCount == 1.
// - All the tiles must have the same operating point (because the codecs take operating point once at initialization
// and do not allow it to be changed later).
// - All the tiles must have the same value for allLayers (because the codecs take allLayers once at initialization
// and do not allow it to be changed later).
// - If the image has a single tile, it must not have a single tile alpha plane (in this case we will steal the planes
// from the decoder, so we cannot use the same decoder for both the color and the alpha planes).
// - All tiles have the same type (AV1 or AV2).
// Otherwise, we will use |tiles.count| decoder instances (one instance for each tile).
avifBool canUseSingleCodecInstance = (data->tiles.count == 1) ||
(decoder->imageCount == 1 && avifTilesCanBeDecodedWithSameCodecInstance(data));
if (canUseSingleCodecInstance) {
AVIF_CHECKRES(avifCodecCreateInternal(decoder->codecChoice, &decoder->data->tiles.tile[0], &decoder->diag, &data->codec));
for (unsigned int i = 0; i < decoder->data->tiles.count; ++i) {
decoder->data->tiles.tile[i].codec = data->codec;
}
} else {
for (unsigned int i = 0; i < decoder->data->tiles.count; ++i) {
avifTile * tile = &decoder->data->tiles.tile[i];
AVIF_CHECKRES(avifCodecCreateInternal(decoder->codecChoice, tile, &decoder->diag, &tile->codec));
}
}
}
return AVIF_RESULT_OK;
}
// Returns the primary color item if found, or NULL.
static avifDecoderItem * avifMetaFindColorItem(avifMeta * meta)
{
for (uint32_t itemIndex = 0; itemIndex < meta->items.count; ++itemIndex) {
avifDecoderItem * item = meta->items.item[itemIndex];
if (avifDecoderItemShouldBeSkipped(item)) {
continue;
}
if (item->id == meta->primaryItemID) {
return item;
}
}
return NULL;
}
// Returns AVIF_TRUE if item is an alpha auxiliary item of the parent color
// item.
static avifBool avifDecoderItemIsAlphaAux(const avifDecoderItem * item, uint32_t colorItemId)
{
if (item->auxForID != colorItemId)
return AVIF_FALSE;
const avifProperty * auxCProp = avifPropertyArrayFind(&item->properties, "auxC");
return auxCProp && isAlphaURN(auxCProp->u.auxC.auxType);
}
// Finds the alpha item whose parent item is colorItem and sets it in the alphaItem output parameter. Returns AVIF_RESULT_OK on
// success. Note that *alphaItem can be NULL even if the return value is AVIF_RESULT_OK. If the colorItem is a grid and the alpha
// item is represented as a set of auxl items to each color tile, then a fake item will be created and *isAlphaItemInInput will be
// set to AVIF_FALSE. In this case, the alpha item merely exists to hold the locations of the alpha tile items. The data of this
// item need not be read and the pixi property cannot be validated. Otherwise, *isAlphaItemInInput will be set to AVIF_TRUE when
// *alphaItem is not NULL.
static avifResult avifMetaFindAlphaItem(avifMeta * meta,
const avifDecoderItem * colorItem,
const avifTileInfo * colorInfo,
avifDecoderItem ** alphaItem,
avifTileInfo * alphaInfo,
avifBool * isAlphaItemInInput)
{
for (uint32_t itemIndex = 0; itemIndex < meta->items.count; ++itemIndex) {
avifDecoderItem * item = meta->items.item[itemIndex];
if (avifDecoderItemShouldBeSkipped(item)) {
continue;
}
if (avifDecoderItemIsAlphaAux(item, colorItem->id)) {
*alphaItem = item;
*isAlphaItemInInput = AVIF_TRUE;
return AVIF_RESULT_OK;
}
}
if (memcmp(colorItem->type, "grid", 4)) {
*alphaItem = NULL;
*isAlphaItemInInput = AVIF_FALSE;
return AVIF_RESULT_OK;
}
// If color item is a grid, check if there is an alpha channel which is represented as an auxl item to each color tile item.
uint32_t colorItemCount = colorInfo->grid.rows * colorInfo->grid.columns;
if (colorItemCount == 0) {
*alphaItem = NULL;
*isAlphaItemInInput = AVIF_FALSE;
return AVIF_RESULT_OK;
}
uint32_t * alphaItemIndices = (uint32_t *)avifAlloc(colorItemCount * sizeof(uint32_t));
AVIF_CHECKERR(alphaItemIndices, AVIF_RESULT_OUT_OF_MEMORY);
uint32_t alphaItemCount = 0;
for (uint32_t i = 0; i < meta->items.count; ++i) {
const avifDecoderItem * const item = meta->items.item[i];
if (item->dimgForID == colorItem->id) {
avifBool seenAlphaForCurrentItem = AVIF_FALSE;
for (uint32_t j = 0; j < meta->items.count; ++j) {
avifDecoderItem * auxlItem = meta->items.item[j];
if (avifDecoderItemIsAlphaAux(auxlItem, item->id)) {
if (seenAlphaForCurrentItem || auxlItem->dimgForID != 0) {
// One of the following invalid cases:
// * Multiple items are claiming to be the alpha auxiliary of the current item.
// * Alpha auxiliary is dimg for another item.
avifFree(alphaItemIndices);
*alphaItem = NULL;
*isAlphaItemInInput = AVIF_FALSE;
return AVIF_RESULT_INVALID_IMAGE_GRID;
}
alphaItemIndices[alphaItemCount++] = j;
seenAlphaForCurrentItem = AVIF_TRUE;
}
}
if (!seenAlphaForCurrentItem) {
// No alpha auxiliary item was found for the current item. Treat this as an image without alpha.
avifFree(alphaItemIndices);
*alphaItem = NULL;
*isAlphaItemInInput = AVIF_FALSE;
return AVIF_RESULT_OK;
}
}
}
AVIF_ASSERT_OR_RETURN(alphaItemCount == colorItemCount);
// Find an unused ID.
avifResult result;
if (meta->items.count >= UINT32_MAX - 1) {
// In the improbable case where all IDs are used.
result = AVIF_RESULT_DECODE_ALPHA_FAILED;
} else {
uint32_t newItemID = 0;
avifBool isUsed;
do {
++newItemID;
isUsed = AVIF_FALSE;
for (uint32_t i = 0; i < meta->items.count; ++i) {
if (meta->items.item[i]->id == newItemID) {
isUsed = AVIF_TRUE;
break;
}
}
} while (isUsed && newItemID != 0);
result = avifMetaFindOrCreateItem(meta, newItemID, alphaItem); // Create new empty item.
}
if (result != AVIF_RESULT_OK) {
avifFree(alphaItemIndices);
*isAlphaItemInInput = AVIF_FALSE;
return result;
}
memcpy((*alphaItem)->type, "grid", 4); // Make it a grid and register alpha items as its tiles.
(*alphaItem)->width = colorItem->width;
(*alphaItem)->height = colorItem->height;
for (uint32_t i = 0; i < alphaItemCount; ++i) {
avifDecoderItem * item = meta->items.item[alphaItemIndices[i]];
item->dimgForID = (*alphaItem)->id;
}
avifFree(alphaItemIndices);
*isAlphaItemInInput = AVIF_FALSE;
alphaInfo->grid = colorInfo->grid;
return AVIF_RESULT_OK;
}
// On success, this function returns AVIF_RESULT_OK and does the following:
// * If a nclx property was found in |properties|:
// - Set |*colorPrimaries|, |*transferCharacteristics|, |*matrixCoefficients|
// and |*yuvRange|.
// - If cicpSet is not NULL, set |*cicpSet| to AVIF_TRUE.
// This function fails if more than one nclx property is found in |properties|.
// The output parameters may be populated even in case of failure and must be
// ignored.
static avifResult avifReadColorNclxProperty(const avifPropertyArray * properties,
avifColorPrimaries * colorPrimaries,
avifTransferCharacteristics * transferCharacteristics,
avifMatrixCoefficients * matrixCoefficients,
avifRange * yuvRange,
avifBool * cicpSet)
{
avifBool colrNCLXSeen = AVIF_FALSE;
for (uint32_t propertyIndex = 0; propertyIndex < properties->count; ++propertyIndex) {
avifProperty * prop = &properties->prop[propertyIndex];
if (!memcmp(prop->type, "colr", 4) && prop->u.colr.hasNCLX) {
if (colrNCLXSeen) {
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
colrNCLXSeen = AVIF_TRUE;
if (cicpSet != NULL) {
*cicpSet = AVIF_TRUE;
}
*colorPrimaries = prop->u.colr.colorPrimaries;
*transferCharacteristics = prop->u.colr.transferCharacteristics;
*matrixCoefficients = prop->u.colr.matrixCoefficients;
*yuvRange = prop->u.colr.range;
}
}
return AVIF_RESULT_OK;
}
// On success, this function returns AVIF_RESULT_OK and does the following:
// * If a colr property was found in |properties|:
// - Read the icc data into |icc| from |io|.
// - Sets the CICP values as documented in avifReadColorNclxProperty().
// This function fails if more than one icc or nclx property is found in
// |properties|. The output parameters may be populated even in case of failure
// and must be ignored (and the |icc| object may need to be freed).
static avifResult avifReadColorProperties(avifIO * io,
const avifPropertyArray * properties,
avifRWData * icc,
avifColorPrimaries * colorPrimaries,
avifTransferCharacteristics * transferCharacteristics,
avifMatrixCoefficients * matrixCoefficients,
avifRange * yuvRange,
avifBool * cicpSet)
{
// Find and adopt all colr boxes "at most one for a given value of colour type" (HEIF 6.5.5.1, from Amendment 3)
// Accept one of each type, and bail out if more than one of a given type is provided.
avifBool colrICCSeen = AVIF_FALSE;
for (uint32_t propertyIndex = 0; propertyIndex < properties->count; ++propertyIndex) {
avifProperty * prop = &properties->prop[propertyIndex];
if (!memcmp(prop->type, "colr", 4) && prop->u.colr.hasICC) {
if (colrICCSeen) {
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
avifROData iccRead;
AVIF_CHECKRES(io->read(io, 0, prop->u.colr.iccOffset, prop->u.colr.iccSize, &iccRead));
colrICCSeen = AVIF_TRUE;
AVIF_CHECKRES(avifRWDataSet(icc, iccRead.data, iccRead.size));
}
}
return avifReadColorNclxProperty(properties, colorPrimaries, transferCharacteristics, matrixCoefficients, yuvRange, cicpSet);
}
#if defined(AVIF_ENABLE_EXPERIMENTAL_GAIN_MAP)
// Finds a 'tmap' (tone mapped image item) box associated with the given 'colorItem'.
// If found, fills 'toneMappedImageItem' and sets 'gainMapItemID' to the id of the gain map
// item associated with the box. Otherwise, sets 'toneMappedImageItem' to NULL.
// Returns AVIF_RESULT_OK if no errors were encountered (whether or not a tmap box was found).
// Assumes that there is a single tmap item, and not, e.g., a grid of tmap items.
// TODO(maryla): add support for files with multiple tmap items if it gets allowed by the spec.
static avifResult avifDecoderDataFindToneMappedImageItem(const avifDecoderData * data,
const avifDecoderItem * colorItem,
avifDecoderItem ** toneMappedImageItem,
uint32_t * gainMapItemID)
{
for (uint32_t itemIndex = 0; itemIndex < data->meta->items.count; ++itemIndex) {
avifDecoderItem * item = data->meta->items.item[itemIndex];
if (!item->size || item->hasUnsupportedEssentialProperty || item->thumbnailForID != 0) {
continue;
}
if (!memcmp(item->type, "tmap", 4)) {
// The tmap box should be associated (via 'iref'->'dimg') to two items:
// the first one is the base image, the second one is the gain map.
uint32_t dimgItemIDs[2] = { 0, 0 };
uint32_t numDimgItemIDs = 0;
for (uint32_t otherItemIndex = 0; otherItemIndex < data->meta->items.count; ++otherItemIndex) {
avifDecoderItem * otherItem = data->meta->items.item[otherItemIndex];
if (otherItem->dimgForID != item->id) {
continue;
}
if (otherItem->dimgIdx < 2) {
AVIF_ASSERT_OR_RETURN(dimgItemIDs[otherItem->dimgIdx] == 0);
dimgItemIDs[otherItem->dimgIdx] = otherItem->id;
}
numDimgItemIDs++;
}
// Even with numDimgItemIDs == 2, one of the ids could be 0 if there are duplicate entries in the 'dimg' box.
if (numDimgItemIDs != 2 || dimgItemIDs[0] == 0 || dimgItemIDs[1] == 0) {
avifDiagnosticsPrintf(data->diag, "box[dimg] for 'tmap' item %d must have exactly 2 entries with distinct ids", item->id);
return AVIF_RESULT_INVALID_TONE_MAPPED_IMAGE;
}
if (dimgItemIDs[0] != colorItem->id) {
continue;
}
*toneMappedImageItem = item;
*gainMapItemID = dimgItemIDs[1];
return AVIF_RESULT_OK;
}
}
*toneMappedImageItem = NULL;
*gainMapItemID = 0;
return AVIF_RESULT_OK;
}
// Finds a 'tmap' (tone mapped image item) box associated with the given 'colorItem',
// then finds the associated gain map image.
// If found, fills 'toneMappedImageItem', 'gainMapItem' and 'gainMapCodecType'.
// Otherwise, sets 'toneMappedImageItem' and 'gainMapItem' to NULL.
// Returns AVIF_RESULT_OK if no errors were encountered (whether or not a gain map was found).
// Assumes that there is a single tmap item, and not, e.g., a grid of tmap items.
static avifResult avifDecoderFindGainMapItem(const avifDecoder * decoder,
const avifDecoderItem * colorItem,
avifDecoderItem ** toneMappedImageItem,
avifDecoderItem ** gainMapItem,
avifCodecType * gainMapCodecType)
{
*toneMappedImageItem = NULL;
*gainMapItem = NULL;
*gainMapCodecType = AVIF_CODEC_TYPE_UNKNOWN;
avifDecoderData * data = decoder->data;
uint32_t gainMapItemID;
avifDecoderItem * toneMappedImageItemTmp;
AVIF_CHECKRES(avifDecoderDataFindToneMappedImageItem(data, colorItem, &toneMappedImageItemTmp, &gainMapItemID));
if (!toneMappedImageItemTmp) {
return AVIF_RESULT_OK;
}
AVIF_ASSERT_OR_RETURN(gainMapItemID != 0);
avifDecoderItem * gainMapItemTmp;
AVIF_CHECKRES(avifMetaFindOrCreateItem(data->meta, gainMapItemID, &gainMapItemTmp));
if (avifDecoderItemShouldBeSkipped(gainMapItemTmp)) {
avifDiagnosticsPrintf(data->diag, "Box[tmap] gain map item %d is not a supported image type", gainMapItemID);
return AVIF_RESULT_INVALID_TONE_MAPPED_IMAGE;
}
AVIF_CHECKRES(avifDecoderItemReadAndParse(decoder,
gainMapItemTmp,
/*isItemInInput=*/AVIF_TRUE,
&data->tileInfos[AVIF_ITEM_GAIN_MAP].grid,
gainMapCodecType));
if (decoder->enableDecodingGainMap || decoder->enableParsingGainMapMetadata) {
decoder->image->gainMap = avifGainMapCreate();
AVIF_CHECKERR(decoder->image->gainMap, AVIF_RESULT_OUT_OF_MEMORY);
}
if (decoder->enableParsingGainMapMetadata) {
avifGainMap * const gainMap = decoder->image->gainMap;
AVIF_CHECKRES(avifReadColorProperties(decoder->io,
&toneMappedImageItemTmp->properties,
&gainMap->altICC,
&gainMap->altColorPrimaries,
&gainMap->altTransferCharacteristics,
&gainMap->altMatrixCoefficients,
&gainMap->altYUVRange,
/*cicpSet=*/NULL));
const avifProperty * clliProp = avifPropertyArrayFind(&toneMappedImageItemTmp->properties, "clli");
if (clliProp) {
gainMap->altCLLI = clliProp->u.clli;
}
const avifProperty * pixiProp = avifPropertyArrayFind(&toneMappedImageItemTmp->properties, "pixi");
if (pixiProp) {
gainMap->altPlaneCount = pixiProp->u.pixi.planeCount;
gainMap->altDepth = pixiProp->u.pixi.planeDepths[0];
}
if (avifPropertyArrayFind(&toneMappedImageItemTmp->properties, "pasp") ||
avifPropertyArrayFind(&toneMappedImageItemTmp->properties, "clap") ||
avifPropertyArrayFind(&toneMappedImageItemTmp->properties, "irot") ||
avifPropertyArrayFind(&toneMappedImageItemTmp->properties, "imir")) {
// libavif requires the bitstream contain the same pasp, clap, irot, imir
// properties for both the base and gain map image items used as input to
// the tone-mapped derived image item. libavif also requires the tone-mapped
// derived image item itself not be associated with these properties. This is
// enforced at encoding. Other patterns are rejected at decoding.
avifDiagnosticsPrintf(data->diag,
"Box[tmap] 'pasp', 'clap', 'irot' and 'imir' properties must be associated with base and gain map items instead of 'tmap'");
return AVIF_RESULT_INVALID_TONE_MAPPED_IMAGE;
}
}
if (decoder->enableDecodingGainMap) {
avifGainMap * const gainMap = decoder->image->gainMap;
gainMap->image = avifImageCreateEmpty();
AVIF_CHECKERR(gainMap->image, AVIF_RESULT_OUT_OF_MEMORY);
// Look for a colr nclx box. Other colr box types (e.g. ICC) are not supported.
AVIF_CHECKRES(avifReadColorNclxProperty(&gainMapItemTmp->properties,
&gainMap->image->colorPrimaries,
&gainMap->image->transferCharacteristics,
&gainMap->image->matrixCoefficients,
&gainMap->image->yuvRange,
/*cicpSet=*/NULL));
}
// Only set the output parameters after everything has been validated.
*toneMappedImageItem = toneMappedImageItemTmp;
*gainMapItem = gainMapItemTmp;
return AVIF_RESULT_OK;
}
static avifResult aviDecoderCheckGainMapProperties(avifDecoder * decoder, const avifPropertyArray * gainMapProperties)
{
const avifImage * image = decoder->image;
// libavif requires the bitstream contain the same 'pasp', 'clap', 'irot', 'imir'
// properties for both the base and gain map image items used as input to
// the tone-mapped derived image item. libavif also requires the tone-mapped
// derived image item itself not be associated with these properties. This is
// enforced at encoding. Other patterns are rejected at decoding.
const avifProperty * paspProp = avifPropertyArrayFind(gainMapProperties, "pasp");
if (!paspProp != !(image->transformFlags & AVIF_TRANSFORM_PASP) ||
(paspProp && (paspProp->u.pasp.hSpacing != image->pasp.hSpacing || paspProp->u.pasp.vSpacing != image->pasp.vSpacing))) {
avifDiagnosticsPrintf(&decoder->diag,
"Pixel aspect ratio property mismatch between input items of tone-mapping derived image item");
return AVIF_RESULT_DECODE_GAIN_MAP_FAILED;
}
const avifProperty * clapProp = avifPropertyArrayFind(gainMapProperties, "clap");
if (!clapProp != !(image->transformFlags & AVIF_TRANSFORM_CLAP) ||
(clapProp && (clapProp->u.clap.widthN != image->clap.widthN || clapProp->u.clap.widthD != image->clap.widthD ||
clapProp->u.clap.heightN != image->clap.heightN || clapProp->u.clap.heightD != image->clap.heightD ||
clapProp->u.clap.horizOffN != image->clap.horizOffN || clapProp->u.clap.horizOffD != image->clap.horizOffD ||
clapProp->u.clap.vertOffN != image->clap.vertOffN || clapProp->u.clap.vertOffD != image->clap.vertOffD))) {
avifDiagnosticsPrintf(&decoder->diag, "Clean aperture property mismatch between input items of tone-mapping derived image item");
return AVIF_RESULT_DECODE_GAIN_MAP_FAILED;
}
const avifProperty * irotProp = avifPropertyArrayFind(gainMapProperties, "irot");
if (!irotProp != !(image->transformFlags & AVIF_TRANSFORM_IROT) || (irotProp && irotProp->u.irot.angle != image->irot.angle)) {
avifDiagnosticsPrintf(&decoder->diag, "Rotation property mismatch between input items of tone-mapping derived image item");
return AVIF_RESULT_DECODE_GAIN_MAP_FAILED;
}
const avifProperty * imirProp = avifPropertyArrayFind(gainMapProperties, "imir");
if (!imirProp != !(image->transformFlags & AVIF_TRANSFORM_IMIR) || (imirProp && imirProp->u.imir.axis != image->imir.axis)) {
avifDiagnosticsPrintf(&decoder->diag, "Mirroring property mismatch between input items of tone-mapping derived image item");
return AVIF_RESULT_DECODE_GAIN_MAP_FAILED;
}
return AVIF_RESULT_OK;
}
#endif // AVIF_ENABLE_EXPERIMENTAL_GAIN_MAP
#if defined(AVIF_ENABLE_EXPERIMENTAL_SAMPLE_TRANSFORM)
// Finds a 'sato' Sample Transform derived image item box.
// If found, fills 'sampleTransformItem'. Otherwise, sets 'sampleTransformItem' to NULL.
// Returns AVIF_RESULT_OK on success (whether or not a 'sato' box was found).
// Assumes that there is a single 'sato' item.
// Assumes that the 'sato' item is not the primary item and that both the primary item and 'sato'
// are in the same 'altr' group.
// TODO(yguyon): Check instead of assuming.
static avifResult avifDecoderDataFindSampleTransformImageItem(avifDecoderData * data, avifDecoderItem ** sampleTransformItem)
{
for (uint32_t itemIndex = 0; itemIndex < data->meta->items.count; ++itemIndex) {
avifDecoderItem * item = data->meta->items.item[itemIndex];
if (!item->size || item->hasUnsupportedEssentialProperty || item->thumbnailForID != 0) {
continue;
}
if (!memcmp(item->type, "sato", 4)) {
*sampleTransformItem = item;
return AVIF_RESULT_OK;
}
}
*sampleTransformItem = NULL;
return AVIF_RESULT_OK;
}
#endif // AVIF_ENABLE_EXPERIMENTAL_SAMPLE_TRANSFORM
static avifResult avifDecoderGenerateImageTiles(avifDecoder * decoder, avifTileInfo * info, avifDecoderItem * item, avifItemCategory itemCategory)
{
const uint32_t previousTileCount = decoder->data->tiles.count;
if ((info->grid.rows > 0) && (info->grid.columns > 0)) {
AVIF_CHECKRES(avifDecoderGenerateImageGridTiles(decoder, &info->grid, item, itemCategory));
} else {
AVIF_CHECKERR(item->size != 0, AVIF_RESULT_MISSING_IMAGE_ITEM);
const avifCodecType codecType = avifGetCodecType(item->type);
AVIF_ASSERT_OR_RETURN(codecType != AVIF_CODEC_TYPE_UNKNOWN);
avifTile * tile =
avifDecoderDataCreateTile(decoder->data, codecType, item->width, item->height, avifDecoderItemOperatingPoint(item));
AVIF_CHECKERR(tile, AVIF_RESULT_OUT_OF_MEMORY);
AVIF_CHECKRES(avifCodecDecodeInputFillFromDecoderItem(tile->input,
item,
decoder->allowProgressive,
decoder->imageCountLimit,
decoder->io->sizeHint,
&decoder->diag));
tile->input->itemCategory = itemCategory;
}
info->tileCount = decoder->data->tiles.count - previousTileCount;
return AVIF_RESULT_OK;
}
// Populates depth, yuvFormat and yuvChromaSamplePosition fields on 'image' based on data from the codec config property (e.g. "av1C").
static avifResult avifReadCodecConfigProperty(avifImage * image, const avifPropertyArray * properties, avifCodecType codecType)
{
const avifProperty * configProp = avifPropertyArrayFind(properties, avifGetConfigurationPropertyName(codecType));
if (configProp) {
image->depth = avifCodecConfigurationBoxGetDepth(&configProp->u.av1C);
if (configProp->u.av1C.monochrome) {
image->yuvFormat = AVIF_PIXEL_FORMAT_YUV400;
} else {
if (configProp->u.av1C.chromaSubsamplingX && configProp->u.av1C.chromaSubsamplingY) {
image->yuvFormat = AVIF_PIXEL_FORMAT_YUV420;
} else if (configProp->u.av1C.chromaSubsamplingX) {
image->yuvFormat = AVIF_PIXEL_FORMAT_YUV422;
} else {
image->yuvFormat = AVIF_PIXEL_FORMAT_YUV444;
}
}
image->yuvChromaSamplePosition = (avifChromaSamplePosition)configProp->u.av1C.chromaSamplePosition;
} else {
// A configuration property box is mandatory in all valid AVIF configurations. Bail out.
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
return AVIF_RESULT_OK;
}
avifResult avifDecoderReset(avifDecoder * decoder)
{
avifDiagnosticsClearError(&decoder->diag);
avifDecoderData * data = decoder->data;
if (!data) {
// Nothing to reset.
return AVIF_RESULT_OK;
}
for (int c = 0; c < AVIF_ITEM_CATEGORY_COUNT; ++c) {
memset(&data->tileInfos[c].grid, 0, sizeof(data->tileInfos[c].grid));
}
avifDecoderDataClearTiles(data);
// Prepare / cleanup decoded image state
if (decoder->image) {
avifImageDestroy(decoder->image);
}
decoder->image = avifImageCreateEmpty();
AVIF_CHECKERR(decoder->image, AVIF_RESULT_OUT_OF_MEMORY);
decoder->progressiveState = AVIF_PROGRESSIVE_STATE_UNAVAILABLE;
data->cicpSet = AVIF_FALSE;
memset(&decoder->ioStats, 0, sizeof(decoder->ioStats));
// -----------------------------------------------------------------------
// Build decode input
data->sourceSampleTable = NULL; // Reset
if (decoder->requestedSource == AVIF_DECODER_SOURCE_AUTO) {
// Honor the major brand (avif or avis) if present, otherwise prefer avis (tracks) if possible.
if (!memcmp(data->majorBrand, "avis", 4)) {
data->source = AVIF_DECODER_SOURCE_TRACKS;
} else if (!memcmp(data->majorBrand, "avif", 4)) {
data->source = AVIF_DECODER_SOURCE_PRIMARY_ITEM;
} else if (data->tracks.count > 0) {
data->source = AVIF_DECODER_SOURCE_TRACKS;
} else {
data->source = AVIF_DECODER_SOURCE_PRIMARY_ITEM;
}
} else {
data->source = decoder->requestedSource;
}
avifCodecType colorCodecType = AVIF_CODEC_TYPE_UNKNOWN;
const avifPropertyArray * colorProperties = NULL;
#if defined(AVIF_ENABLE_EXPERIMENTAL_GAIN_MAP)
const avifPropertyArray * gainMapProperties = NULL;
#endif
if (data->source == AVIF_DECODER_SOURCE_TRACKS) {
avifTrack * colorTrack = NULL;
avifTrack * alphaTrack = NULL;
// Find primary track - this probably needs some better detection
uint32_t colorTrackIndex = 0;
for (; colorTrackIndex < data->tracks.count; ++colorTrackIndex) {
avifTrack * track = &data->tracks.track[colorTrackIndex];
if (!track->sampleTable) {
continue;
}
if (!track->id) { // trak box might be missing a tkhd box inside, skip it
continue;
}
if (!track->sampleTable->chunks.count) {
continue;
}
colorCodecType = avifSampleTableGetCodecType(track->sampleTable);
if (colorCodecType == AVIF_CODEC_TYPE_UNKNOWN) {
continue;
}
if (track->auxForID != 0) {
continue;
}
// Found one!
break;
}
if (colorTrackIndex == data->tracks.count) {
avifDiagnosticsPrintf(&decoder->diag, "Failed to find AV1 color track");
return AVIF_RESULT_NO_CONTENT;
}
colorTrack = &data->tracks.track[colorTrackIndex];
colorProperties = avifSampleTableGetProperties(colorTrack->sampleTable, colorCodecType);
if (!colorProperties) {
avifDiagnosticsPrintf(&decoder->diag, "Failed to find AV1 color track's color properties");
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
// Find Exif and/or XMP metadata, if any
if (colorTrack->meta) {
// See the comment above avifDecoderFindMetadata() for the explanation of using 0 here
avifResult findResult = avifDecoderFindMetadata(decoder, colorTrack->meta, decoder->image, 0);
if (findResult != AVIF_RESULT_OK) {
return findResult;
}
}
uint32_t alphaTrackIndex = 0;
avifCodecType alphaCodecType = AVIF_CODEC_TYPE_UNKNOWN;
for (; alphaTrackIndex < data->tracks.count; ++alphaTrackIndex) {
avifTrack * track = &data->tracks.track[alphaTrackIndex];
if (!track->sampleTable) {
continue;
}
if (!track->id) {
continue;
}
if (!track->sampleTable->chunks.count) {
continue;
}
alphaCodecType = avifSampleTableGetCodecType(track->sampleTable);
if (alphaCodecType == AVIF_CODEC_TYPE_UNKNOWN) {
continue;
}
if (track->auxForID == colorTrack->id) {
// Found it!
break;
}
}
if (alphaTrackIndex != data->tracks.count) {
alphaTrack = &data->tracks.track[alphaTrackIndex];
}
const uint8_t operatingPoint = 0; // No way to set operating point via tracks
avifTile * colorTile = avifDecoderDataCreateTile(data, colorCodecType, colorTrack->width, colorTrack->height, operatingPoint);
AVIF_CHECKERR(colorTile != NULL, AVIF_RESULT_OUT_OF_MEMORY);
AVIF_CHECKRES(avifCodecDecodeInputFillFromSampleTable(colorTile->input,
colorTrack->sampleTable,
decoder->imageCountLimit,
decoder->io->sizeHint,
data->diag));
data->tileInfos[AVIF_ITEM_COLOR].tileCount = 1;
if (alphaTrack) {
avifTile * alphaTile = avifDecoderDataCreateTile(data, alphaCodecType, alphaTrack->width, alphaTrack->height, operatingPoint);
AVIF_CHECKERR(alphaTile != NULL, AVIF_RESULT_OUT_OF_MEMORY);
AVIF_CHECKRES(avifCodecDecodeInputFillFromSampleTable(alphaTile->input,
alphaTrack->sampleTable,
decoder->imageCountLimit,
decoder->io->sizeHint,
data->diag));
alphaTile->input->itemCategory = AVIF_ITEM_ALPHA;
data->tileInfos[AVIF_ITEM_ALPHA].tileCount = 1;
}
// Stash off sample table for future timing information
data->sourceSampleTable = colorTrack->sampleTable;
// Image sequence timing
decoder->imageIndex = -1;
decoder->imageCount = (int)colorTile->input->samples.count;
decoder->timescale = colorTrack->mediaTimescale;
decoder->durationInTimescales = colorTrack->mediaDuration;
if (colorTrack->mediaTimescale) {
decoder->duration = (double)decoder->durationInTimescales / (double)colorTrack->mediaTimescale;
} else {
decoder->duration = 0;
}
// If the alphaTrack->repetitionCount and colorTrack->repetitionCount are different, we will simply use the
// colorTrack's repetitionCount.
decoder->repetitionCount = colorTrack->repetitionCount;
memset(&decoder->imageTiming, 0, sizeof(decoder->imageTiming)); // to be set in avifDecoderNextImage()
decoder->image->width = colorTrack->width;
decoder->image->height = colorTrack->height;
decoder->alphaPresent = (alphaTrack != NULL);
decoder->image->alphaPremultiplied = decoder->alphaPresent && (colorTrack->premByID == alphaTrack->id);
} else {
// Create from items
if (data->meta->primaryItemID == 0) {
// A primary item is required
avifDiagnosticsPrintf(&decoder->diag, "Primary item not specified");
return AVIF_RESULT_MISSING_IMAGE_ITEM;
}
// Main item of each group category (top-level item such as grid or single tile), if any.
avifDecoderItem * mainItems[AVIF_ITEM_CATEGORY_COUNT];
avifCodecType codecType[AVIF_ITEM_CATEGORY_COUNT];
for (int c = 0; c < AVIF_ITEM_CATEGORY_COUNT; ++c) {
mainItems[c] = NULL;
codecType[c] = AVIF_CODEC_TYPE_UNKNOWN;
}
// Mandatory primary color item
mainItems[AVIF_ITEM_COLOR] = avifMetaFindColorItem(data->meta);
if (!mainItems[AVIF_ITEM_COLOR]) {
avifDiagnosticsPrintf(&decoder->diag, "Primary item not found");
return AVIF_RESULT_MISSING_IMAGE_ITEM;
}
AVIF_CHECKRES(avifDecoderItemReadAndParse(decoder,
mainItems[AVIF_ITEM_COLOR],
/*isItemInInput=*/AVIF_TRUE,
&data->tileInfos[AVIF_ITEM_COLOR].grid,
&codecType[AVIF_ITEM_COLOR]));
colorProperties = &mainItems[AVIF_ITEM_COLOR]->properties;
colorCodecType = codecType[AVIF_ITEM_COLOR];
// Optional alpha auxiliary item
avifBool isAlphaItemInInput;
AVIF_CHECKRES(avifMetaFindAlphaItem(data->meta,
mainItems[AVIF_ITEM_COLOR],
&data->tileInfos[AVIF_ITEM_COLOR],
&mainItems[AVIF_ITEM_ALPHA],
&data->tileInfos[AVIF_ITEM_ALPHA],
&isAlphaItemInInput));
if (mainItems[AVIF_ITEM_ALPHA]) {
AVIF_CHECKRES(avifDecoderItemReadAndParse(decoder,
mainItems[AVIF_ITEM_ALPHA],
isAlphaItemInInput,
&data->tileInfos[AVIF_ITEM_ALPHA].grid,
&codecType[AVIF_ITEM_ALPHA]));
}
#if defined(AVIF_ENABLE_EXPERIMENTAL_GAIN_MAP)
avifDecoderItem * toneMappedImageItem;
const avifResult findGainMapResult = avifDecoderFindGainMapItem(decoder,
mainItems[AVIF_ITEM_COLOR],
&toneMappedImageItem,
&mainItems[AVIF_ITEM_GAIN_MAP],
&codecType[AVIF_ITEM_GAIN_MAP]);
if (!decoder->enableDecodingGainMap) {
// When ignoring the gain map, we still report whether one is present or not,
// but do not fail if there was any error with the gain map.
if (findGainMapResult != AVIF_RESULT_OK) {
// Only ignore reproducible errors (caused by the bitstream and not by the environment).
AVIF_CHECKERR(findGainMapResult != AVIF_RESULT_OUT_OF_MEMORY, findGainMapResult);
// Clear diagnostic message.
avifDiagnosticsClearError(data->diag);
}
decoder->gainMapPresent = (mainItems[AVIF_ITEM_GAIN_MAP] != NULL);
// We also ignore the actual item and don't decode it.
mainItems[AVIF_ITEM_GAIN_MAP] = NULL;
} else {
AVIF_CHECKRES(findGainMapResult);
}
if (toneMappedImageItem != NULL && decoder->enableParsingGainMapMetadata) {
// Read the gain map's metadata.
avifROData tmapData;
AVIF_CHECKRES(avifDecoderItemRead(toneMappedImageItem, decoder->io, &tmapData, 0, 0, data->diag));
if (decoder->image->gainMap == NULL) {
decoder->image->gainMap = avifGainMapCreate();
AVIF_CHECKERR(decoder->image->gainMap, AVIF_RESULT_OUT_OF_MEMORY);
}
AVIF_CHECKERR(avifParseToneMappedImageBox(&decoder->image->gainMap->metadata, tmapData.data, tmapData.size, data->diag),
AVIF_RESULT_INVALID_TONE_MAPPED_IMAGE);
}
#endif // AVIF_ENABLE_EXPERIMENTAL_GAIN_MAP
#if defined(AVIF_ENABLE_EXPERIMENTAL_SAMPLE_TRANSFORM)
// AVIF_ITEM_SAMPLE_TRANSFORM (not used through mainItems because not a coded item (well grids are not coded items either but it's different)).
avifDecoderItem * sampleTransformItem = NULL;
AVIF_CHECKRES(avifDecoderDataFindSampleTransformImageItem(data, &sampleTransformItem));
if (sampleTransformItem != NULL) {
AVIF_ASSERT_OR_RETURN(data->sampleTransformNumInputImageItems == 0);
uint32_t numExtraInputImageItems = 0;
for (uint32_t i = 0; i < data->meta->items.count; ++i) {
avifDecoderItem * inputImageItem = data->meta->items.item[i];
if (inputImageItem->dimgForID != sampleTransformItem->id) {
continue;
}
if (avifDecoderItemShouldBeSkipped(inputImageItem)) {
avifDiagnosticsPrintf(data->diag, "Box[sato] input item %d is not a supported image type", inputImageItem->id);
return AVIF_RESULT_DECODE_SAMPLE_TRANSFORM_FAILED;
}
// Input image item order is important because input image items are indexed according to this order.
AVIF_CHECKERR(inputImageItem->dimgIdx == data->sampleTransformNumInputImageItems, AVIF_RESULT_NOT_IMPLEMENTED);
AVIF_CHECKERR(data->sampleTransformNumInputImageItems < AVIF_SAMPLE_TRANSFORM_MAX_NUM_INPUT_IMAGE_ITEMS,
AVIF_RESULT_NOT_IMPLEMENTED);
avifItemCategory * category = &data->sampleTransformInputImageItems[data->sampleTransformNumInputImageItems];
avifBool foundItem = AVIF_FALSE;
uint32_t alphaCategory = AVIF_ITEM_CATEGORY_COUNT;
for (int c = AVIF_ITEM_COLOR; c < AVIF_ITEM_CATEGORY_COUNT; ++c) {
if (mainItems[c] && inputImageItem->id == mainItems[c]->id) {
*category = c;
AVIF_CHECKERR(*category == AVIF_ITEM_COLOR, AVIF_RESULT_NOT_IMPLEMENTED);
alphaCategory = AVIF_ITEM_ALPHA;
foundItem = AVIF_TRUE;
break;
}
}
if (!foundItem) {
AVIF_CHECKERR(numExtraInputImageItems < AVIF_SAMPLE_TRANSFORM_MAX_NUM_EXTRA_INPUT_IMAGE_ITEMS,
AVIF_RESULT_NOT_IMPLEMENTED);
*category = AVIF_ITEM_SAMPLE_TRANSFORM_INPUT_0_COLOR + numExtraInputImageItems;
alphaCategory = AVIF_ITEM_SAMPLE_TRANSFORM_INPUT_0_ALPHA + numExtraInputImageItems;
mainItems[*category] = inputImageItem;
++numExtraInputImageItems;
AVIF_CHECKRES(avifDecoderItemReadAndParse(decoder,
inputImageItem,
/*isItemInInput=*/AVIF_TRUE,
&data->tileInfos[*category].grid,
&codecType[*category]));
// Optional alpha auxiliary item
avifBool isAlphaInputImageItemInInput = AVIF_FALSE;
AVIF_CHECKRES(avifMetaFindAlphaItem(data->meta,
mainItems[*category],
&data->tileInfos[*category],
&mainItems[alphaCategory],
&data->tileInfos[alphaCategory],
&isAlphaInputImageItemInInput));
AVIF_CHECKERR(!mainItems[alphaCategory] == !mainItems[AVIF_ITEM_ALPHA], AVIF_RESULT_NOT_IMPLEMENTED);
if (mainItems[alphaCategory] != NULL) {
AVIF_CHECKERR(isAlphaInputImageItemInInput == isAlphaItemInInput, AVIF_RESULT_NOT_IMPLEMENTED);
AVIF_CHECKERR((mainItems[*category]->premByID == mainItems[alphaCategory]->id) ==
(mainItems[AVIF_ITEM_COLOR]->premByID == mainItems[AVIF_ITEM_ALPHA]->id),
AVIF_RESULT_NOT_IMPLEMENTED);
AVIF_CHECKRES(avifDecoderItemReadAndParse(decoder,
mainItems[alphaCategory],
isAlphaInputImageItemInInput,
&data->tileInfos[alphaCategory].grid,
&codecType[alphaCategory]));
}
}
++data->sampleTransformNumInputImageItems;
}
AVIF_ASSERT_OR_RETURN(data->meta->sampleTransformExpression.tokens == NULL);
avifROData satoData;
AVIF_CHECKRES(avifDecoderItemRead(sampleTransformItem, decoder->io, &satoData, 0, 0, data->diag));
AVIF_CHECKRES(avifParseSampleTransformImageBox(satoData.data,
satoData.size,
data->sampleTransformNumInputImageItems,
&data->meta->sampleTransformExpression,
data->diag));
AVIF_CHECKRES(avifDecoderSampleTransformItemValidateProperties(sampleTransformItem, data->diag));
const avifProperty * pixiProp = avifPropertyArrayFind(&sampleTransformItem->properties, "pixi");
AVIF_ASSERT_OR_RETURN(pixiProp != NULL);
data->meta->sampleTransformDepth = pixiProp->u.pixi.planeDepths[0];
}
#endif // AVIF_ENABLE_EXPERIMENTAL_GAIN_MAP
// Find Exif and/or XMP metadata, if any
AVIF_CHECKRES(avifDecoderFindMetadata(decoder, data->meta, decoder->image, mainItems[AVIF_ITEM_COLOR]->id));
// Set all counts and timing to safe-but-uninteresting values
decoder->imageIndex = -1;
decoder->imageCount = 1;
decoder->imageTiming.timescale = 1;
decoder->imageTiming.pts = 0;
decoder->imageTiming.ptsInTimescales = 0;
decoder->imageTiming.duration = 1;
decoder->imageTiming.durationInTimescales = 1;
decoder->timescale = 1;
decoder->duration = 1;
decoder->durationInTimescales = 1;
for (int c = AVIF_ITEM_COLOR; c < AVIF_ITEM_CATEGORY_COUNT; ++c) {
if (!mainItems[c]) {
continue;
}
#if defined(AVIF_ENABLE_EXPERIMENTAL_GAIN_MAP)
if (decoder->ignoreColorAndAlpha && (c == AVIF_ITEM_COLOR || c == AVIF_ITEM_ALPHA)) {
continue;
}
#endif
if (avifIsAlpha((avifItemCategory)c) && !mainItems[c]->width && !mainItems[c]->height) {
// NON-STANDARD: Alpha subimage does not have an ispe property; adopt width/height from color item
AVIF_ASSERT_OR_RETURN(!(decoder->strictFlags & AVIF_STRICT_ALPHA_ISPE_REQUIRED));
mainItems[c]->width = mainItems[AVIF_ITEM_COLOR]->width;
mainItems[c]->height = mainItems[AVIF_ITEM_COLOR]->height;
}
AVIF_CHECKRES(avifDecoderGenerateImageTiles(decoder, &data->tileInfos[c], mainItems[c], (avifItemCategory)c));
avifStrictFlags strictFlags = decoder->strictFlags;
if (avifIsAlpha((avifItemCategory)c) && !isAlphaItemInInput) {
// In this case, the made up grid item will not have an associated pixi property. So validate everything else
// but the pixi property.
strictFlags &= ~AVIF_STRICT_PIXI_REQUIRED;
}
AVIF_CHECKRES(
avifDecoderItemValidateProperties(mainItems[c], avifGetConfigurationPropertyName(codecType[c]), &decoder->diag, strictFlags));
}
if (mainItems[AVIF_ITEM_COLOR]->progressive) {
decoder->progressiveState = AVIF_PROGRESSIVE_STATE_AVAILABLE;
// data->tileInfos[AVIF_ITEM_COLOR].firstTileIndex is not yet defined but will be set to 0 a few lines below.
const avifTile * colorTile = &data->tiles.tile[0];
if (colorTile->input->samples.count > 1) {
decoder->progressiveState = AVIF_PROGRESSIVE_STATE_ACTIVE;
decoder->imageCount = (int)colorTile->input->samples.count;
}
}
decoder->image->width = mainItems[AVIF_ITEM_COLOR]->width;
decoder->image->height = mainItems[AVIF_ITEM_COLOR]->height;
decoder->alphaPresent = (mainItems[AVIF_ITEM_ALPHA] != NULL);
decoder->image->alphaPremultiplied = decoder->alphaPresent &&
(mainItems[AVIF_ITEM_COLOR]->premByID == mainItems[AVIF_ITEM_ALPHA]->id);
#if defined(AVIF_ENABLE_EXPERIMENTAL_GAIN_MAP)
if (mainItems[AVIF_ITEM_GAIN_MAP]) {
AVIF_ASSERT_OR_RETURN(decoder->image->gainMap && decoder->image->gainMap->image);
decoder->image->gainMap->image->width = mainItems[AVIF_ITEM_GAIN_MAP]->width;
decoder->image->gainMap->image->height = mainItems[AVIF_ITEM_GAIN_MAP]->height;
decoder->gainMapPresent = AVIF_TRUE;
// Must be called after avifDecoderGenerateImageTiles() which among other things copies the
// codec config property from the first tile of a grid to the grid item (when grids are used).
AVIF_CHECKRES(avifReadCodecConfigProperty(decoder->image->gainMap->image,
&mainItems[AVIF_ITEM_GAIN_MAP]->properties,
codecType[AVIF_ITEM_GAIN_MAP]));
gainMapProperties = &mainItems[AVIF_ITEM_GAIN_MAP]->properties;
}
#endif
}
uint32_t firstTileIndex = 0;
for (int c = 0; c < AVIF_ITEM_CATEGORY_COUNT; ++c) {
data->tileInfos[c].firstTileIndex = firstTileIndex;
firstTileIndex += data->tileInfos[c].tileCount;
}
// Sanity check tiles
for (uint32_t tileIndex = 0; tileIndex < data->tiles.count; ++tileIndex) {
avifTile * tile = &data->tiles.tile[tileIndex];
for (uint32_t sampleIndex = 0; sampleIndex < tile->input->samples.count; ++sampleIndex) {
avifDecodeSample * sample = &tile->input->samples.sample[sampleIndex];
if (!sample->size) {
// Every sample must have some data
return AVIF_RESULT_BMFF_PARSE_FAILED;
}
if (tile->input->itemCategory == AVIF_ITEM_COLOR) {
decoder->ioStats.colorOBUSize += sample->size;
} else if (tile->input->itemCategory == AVIF_ITEM_ALPHA) {
decoder->ioStats.alphaOBUSize += sample->size;
}
}
}
AVIF_CHECKRES(avifReadColorProperties(decoder->io,
colorProperties,
&decoder->image->icc,
&decoder->image->colorPrimaries,
&decoder->image->transferCharacteristics,
&decoder->image->matrixCoefficients,
&decoder->image->yuvRange,
&data->cicpSet));
const avifProperty * clliProp = avifPropertyArrayFind(colorProperties, "clli");
if (clliProp) {
decoder->image->clli = clliProp->u.clli;
}
// Transformations
const avifProperty * paspProp = avifPropertyArrayFind(colorProperties, "pasp");
if (paspProp) {
decoder->image->transformFlags |= AVIF_TRANSFORM_PASP;
decoder->image->pasp = paspProp->u.pasp;
}
const avifProperty * clapProp = avifPropertyArrayFind(colorProperties, "clap");
if (clapProp) {
decoder->image->transformFlags |= AVIF_TRANSFORM_CLAP;
decoder->image->clap = clapProp->u.clap;
}
const avifProperty * irotProp = avifPropertyArrayFind(colorProperties, "irot");
if (irotProp) {
decoder->image->transformFlags |= AVIF_TRANSFORM_IROT;
decoder->image->irot = irotProp->u.irot;
}
const avifProperty * imirProp = avifPropertyArrayFind(colorProperties, "imir");
if (imirProp) {
decoder->image->transformFlags |= AVIF_TRANSFORM_IMIR;
decoder->image->imir = imirProp->u.imir;
}
#if defined(AVIF_ENABLE_EXPERIMENTAL_GAIN_MAP)
if (gainMapProperties != NULL) {
AVIF_CHECKRES(aviDecoderCheckGainMapProperties(decoder, gainMapProperties));
}
#endif
if (!data->cicpSet && (data->tiles.count > 0)) {
avifTile * firstTile = &data->tiles.tile[0];
if (firstTile->input->samples.count > 0) {
avifDecodeSample * sample = &firstTile->input->samples.sample[0];
// Harvest CICP from the AV1's sequence header, which should be very close to the front
// of the first sample. Read in successively larger chunks until we successfully parse the sequence.
static const size_t searchSampleChunkIncrement = 64;
static const size_t searchSampleSizeMax = 4096;
size_t searchSampleSize = 0;
do {
searchSampleSize += searchSampleChunkIncrement;
if (searchSampleSize > sample->size) {
searchSampleSize = sample->size;
}
avifResult prepareResult = avifDecoderPrepareSample(decoder, sample, searchSampleSize);
if (prepareResult != AVIF_RESULT_OK) {
return prepareResult;
}
avifSequenceHeader sequenceHeader;
if (avifSequenceHeaderParse(&sequenceHeader, &sample->data, firstTile->codecType)) {
data->cicpSet = AVIF_TRUE;
decoder->image->colorPrimaries = sequenceHeader.colorPrimaries;
decoder->image->transferCharacteristics = sequenceHeader.transferCharacteristics;
decoder->image->matrixCoefficients = sequenceHeader.matrixCoefficients;
decoder->image->yuvRange = sequenceHeader.range;
break;
}
} while (searchSampleSize != sample->size && searchSampleSize < searchSampleSizeMax);
}
}
AVIF_CHECKRES(avifReadCodecConfigProperty(decoder->image, colorProperties, colorCodecType));
return AVIF_RESULT_OK;
}
static avifResult avifDecoderPrepareTiles(avifDecoder * decoder, uint32_t nextImageIndex, const avifTileInfo * info)
{
for (unsigned int tileIndex = info->decodedTileCount; tileIndex < info->tileCount; ++tileIndex) {
avifTile * tile = &decoder->data->tiles.tile[info->firstTileIndex + tileIndex];
if (nextImageIndex >= tile->input->samples.count) {
return AVIF_RESULT_NO_IMAGES_REMAINING;
}
avifDecodeSample * sample = &tile->input->samples.sample[nextImageIndex];
avifResult prepareResult = avifDecoderPrepareSample(decoder, sample, 0);
if (prepareResult != AVIF_RESULT_OK) {
return prepareResult;
}
}
return AVIF_RESULT_OK;
}
static avifResult avifImageLimitedToFullAlpha(avifImage * image)
{
if (image->imageOwnsAlphaPlane) {
return AVIF_RESULT_NOT_IMPLEMENTED;
}
const uint8_t * alphaPlane = image->alphaPlane;
const uint32_t alphaRowBytes = image->alphaRowBytes;
// We cannot do the range conversion in place since it will modify the
// codec's internal frame buffers. Allocate memory for the conversion.
image->alphaPlane = NULL;
image->alphaRowBytes = 0;
const avifResult allocationResult = avifImageAllocatePlanes(image, AVIF_PLANES_A);
if (allocationResult != AVIF_RESULT_OK) {
return allocationResult;
}
if (image->depth > 8) {
for (uint32_t j = 0; j < image->height; ++j) {
const uint8_t * srcRow = &alphaPlane[j * alphaRowBytes];
uint8_t * dstRow = &image->alphaPlane[j * image->alphaRowBytes];
for (uint32_t i = 0; i < image->width; ++i) {
int srcAlpha = *((const uint16_t *)&srcRow[i * 2]);
int dstAlpha = avifLimitedToFullY(image->depth, srcAlpha);
*((uint16_t *)&dstRow[i * 2]) = (uint16_t)dstAlpha;
}
}
} else {
for (uint32_t j = 0; j < image->height; ++j) {
const uint8_t * srcRow = &alphaPlane[j * alphaRowBytes];
uint8_t * dstRow = &image->alphaPlane[j * image->alphaRowBytes];
for (uint32_t i = 0; i < image->width; ++i) {
int srcAlpha = srcRow[i];
int dstAlpha = avifLimitedToFullY(image->depth, srcAlpha);
dstRow[i] = (uint8_t)dstAlpha;
}
}
}
return AVIF_RESULT_OK;
}
static avifResult avifGetErrorForItemCategory(avifItemCategory itemCategory)
{
#if defined(AVIF_ENABLE_EXPERIMENTAL_GAIN_MAP)
if (itemCategory == AVIF_ITEM_GAIN_MAP) {
return AVIF_RESULT_DECODE_GAIN_MAP_FAILED;
}
#endif
#if defined(AVIF_ENABLE_EXPERIMENTAL_SAMPLE_TRANSFORM)
if (itemCategory >= AVIF_SAMPLE_TRANSFORM_MIN_CATEGORY && itemCategory <= AVIF_SAMPLE_TRANSFORM_MAX_CATEGORY) {
return AVIF_RESULT_DECODE_SAMPLE_TRANSFORM_FAILED;
}
#endif
return avifIsAlpha(itemCategory) ? AVIF_RESULT_DECODE_ALPHA_FAILED : AVIF_RESULT_DECODE_COLOR_FAILED;
}
static avifResult avifDecoderDecodeTiles(avifDecoder * decoder, uint32_t nextImageIndex, avifTileInfo * info)
{
const unsigned int oldDecodedTileCount = info->decodedTileCount;
for (unsigned int tileIndex = oldDecodedTileCount; tileIndex < info->tileCount; ++tileIndex) {
avifTile * tile = &decoder->data->tiles.tile[info->firstTileIndex + tileIndex];
const avifDecodeSample * sample = &tile->input->samples.sample[nextImageIndex];
if (sample->data.size < sample->size) {
AVIF_ASSERT_OR_RETURN(decoder->allowIncremental);
// Data is missing but there is no error yet. Output available pixel rows.
return AVIF_RESULT_OK;
}
avifBool isLimitedRangeAlpha = AVIF_FALSE;
if (!tile->codec->getNextImage(tile->codec, decoder, sample, avifIsAlpha(tile->input->itemCategory), &isLimitedRangeAlpha, tile->image)) {
avifDiagnosticsPrintf(&decoder->diag, "tile->codec->getNextImage() failed");
return avifGetErrorForItemCategory(tile->input->itemCategory);
}
// Section 2.3.4 of AV1 Codec ISO Media File Format Binding v1.2.0 says:
// the full_range_flag in the colr box shall match the color_range
// flag in the Sequence Header OBU.
// See https://aomediacodec.github.io/av1-isobmff/v1.2.0.html#av1codecconfigurationbox-semantics.
// If a 'colr' box of colour_type 'nclx' was parsed, a mismatch between
// the 'colr' decoder->image->yuvRange and the AV1 OBU
// tile->image->yuvRange should be treated as an error.
// However codec_svt.c was not encoding the color_range field for
// multiple years, so there probably are files in the wild that will
// fail decoding if this is enforced. Thus this pattern is allowed.
// Section 12.1.5.1 of ISO 14496-12 (ISOBMFF) says:
// If colour information is supplied in both this [colr] box, and also
// in the video bitstream, this box takes precedence, and over-rides
// the information in the bitstream.
// So decoder->image->yuvRange is kept because it was either the 'colr'
// value set when the 'colr' box was parsed, or it was the AV1 OBU value
// extracted from the sequence header OBU of the first tile of the first
// frame (if no 'colr' box of colour_type 'nclx' was found).
// Alpha plane with limited range is not allowed by the latest revision
// of the specification. However, it was allowed in version 1.0.0 of the
// specification. To allow such files, simply convert the alpha plane to
// full range.
if (avifIsAlpha(tile->input->itemCategory) && isLimitedRangeAlpha) {
avifResult result = avifImageLimitedToFullAlpha(tile->image);
if (result != AVIF_RESULT_OK) {
avifDiagnosticsPrintf(&decoder->diag, "avifImageLimitedToFullAlpha failed");
return result;
}
}
// Scale the decoded image so that it corresponds to this tile's output dimensions
if ((tile->width != tile->image->width) || (tile->height != tile->image->height)) {
if (avifImageScaleWithLimit(tile->image,
tile->width,
tile->height,
decoder->imageSizeLimit,
decoder->imageDimensionLimit,
&decoder->diag) != AVIF_RESULT_OK) {
return avifGetErrorForItemCategory(tile->input->itemCategory);
}
}
++info->decodedTileCount;
const avifBool isGrid = (info->grid.rows > 0) && (info->grid.columns > 0);
avifBool stealPlanes = !isGrid;
#if defined(AVIF_ENABLE_EXPERIMENTAL_SAMPLE_TRANSFORM)
if (decoder->data->meta->sampleTransformExpression.count > 0) {
// Keep everything as a copy for now.
stealPlanes = AVIF_FALSE;
}
if (tile->input->itemCategory >= AVIF_SAMPLE_TRANSFORM_MIN_CATEGORY &&
tile->input->itemCategory <= AVIF_SAMPLE_TRANSFORM_MAX_CATEGORY) {
// Keep Sample Transform input image item samples in tiles.
// The expression will be applied in avifDecoderNextImage() below instead, once all the tiles are available.
continue;
}
#endif
if (!stealPlanes) {
avifImage * dstImage = decoder->image;
#if defined(AVIF_ENABLE_EXPERIMENTAL_GAIN_MAP)
if (tile->input->itemCategory == AVIF_ITEM_GAIN_MAP) {
AVIF_ASSERT_OR_RETURN(dstImage->gainMap && dstImage->gainMap->image);
dstImage = dstImage->gainMap->image;
}
#endif
if (tileIndex == 0) {
AVIF_CHECKRES(avifDecoderDataAllocateImagePlanes(decoder->data, info, dstImage));
}
AVIF_CHECKRES(avifDecoderDataCopyTileToImage(decoder->data, info, dstImage, tile, tileIndex));
} else {
AVIF_ASSERT_OR_RETURN(info->tileCount == 1);
AVIF_ASSERT_OR_RETURN(tileIndex == 0);
avifImage * src = tile->image;
switch (tile->input->itemCategory) {
#if defined(AVIF_ENABLE_EXPERIMENTAL_GAIN_MAP)
case AVIF_ITEM_GAIN_MAP:
AVIF_ASSERT_OR_RETURN(decoder->image->gainMap && decoder->image->gainMap->image);
decoder->image->gainMap->image->width = src->width;
decoder->image->gainMap->image->height = src->height;
decoder->image->gainMap->image->depth = src->depth;
break;
#endif
default:
if ((decoder->image->width != src->width) || (decoder->image->height != src->height) ||
(decoder->image->depth != src->depth)) {
if (avifIsAlpha(tile->input->itemCategory)) {
avifDiagnosticsPrintf(&decoder->diag,
"The color image item does not match the alpha image item in width, height, or bit depth");
return AVIF_RESULT_DECODE_ALPHA_FAILED;
}
avifImageFreePlanes(decoder->image, AVIF_PLANES_ALL);
decoder->image->width = src->width;
decoder->image->height = src->height;
decoder->image->depth = src->depth;
}
break;
}
if (avifIsAlpha(tile->input->itemCategory)) {
avifImageStealPlanes(decoder->image, src, AVIF_PLANES_A);
#if defined(AVIF_ENABLE_EXPERIMENTAL_GAIN_MAP)
} else if (tile->input->itemCategory == AVIF_ITEM_GAIN_MAP) {
AVIF_ASSERT_OR_RETURN(decoder->image->gainMap && decoder->image->gainMap->image);
avifImageStealPlanes(decoder->image->gainMap->image, src, AVIF_PLANES_YUV);
#endif
} else { // AVIF_ITEM_COLOR
avifImageStealPlanes(decoder->image, src, AVIF_PLANES_YUV);
}
}
}
return AVIF_RESULT_OK;
}
// Returns AVIF_FALSE if there is currently a partially decoded frame.
static avifBool avifDecoderDataFrameFullyDecoded(const avifDecoderData * data)
{
for (int c = 0; c < AVIF_ITEM_CATEGORY_COUNT; ++c) {
if (data->tileInfos[c].decodedTileCount != data->tileInfos[c].tileCount) {
return AVIF_FALSE;
}
}
return AVIF_TRUE;
}
#if defined(AVIF_ENABLE_EXPERIMENTAL_SAMPLE_TRANSFORM)
avifResult avifDecoderApplySampleTransform(const avifDecoder * decoder, avifImage * dstImage)
{
if (dstImage->depth != decoder->data->meta->sampleTransformDepth) {
AVIF_ASSERT_OR_RETURN(dstImage->yuvPlanes[0] != NULL);
AVIF_ASSERT_OR_RETURN(dstImage->imageOwnsYUVPlanes);
// Use a temporary buffer because dstImage may point to decoder->image, which could be an input image.
avifImage * dstImageWithCorrectDepth =
avifImageCreate(dstImage->width, dstImage->height, decoder->data->meta->sampleTransformDepth, dstImage->yuvFormat);
AVIF_CHECKERR(dstImageWithCorrectDepth != NULL, AVIF_RESULT_OUT_OF_MEMORY);
avifResult result =
avifImageAllocatePlanes(dstImageWithCorrectDepth, dstImage->alphaPlane != NULL ? AVIF_PLANES_ALL : AVIF_PLANES_YUV);
if (result == AVIF_RESULT_OK) {
result = avifDecoderApplySampleTransform(decoder, dstImageWithCorrectDepth);
if (result == AVIF_RESULT_OK) {
// Keep the same dstImage object rather than swapping decoder->image, in case the user already accessed it.
avifImageFreePlanes(dstImage, AVIF_PLANES_ALL);
dstImage->depth = dstImageWithCorrectDepth->depth;
avifImageStealPlanes(dstImage, dstImageWithCorrectDepth, AVIF_PLANES_ALL);
}
}
avifImageDestroy(dstImageWithCorrectDepth);
return result;
}
for (avifBool alpha = AVIF_FALSE; alpha <= decoder->alphaPresent ? AVIF_TRUE : AVIF_FALSE; ++alpha) {
AVIF_ASSERT_OR_RETURN(decoder->data->sampleTransformNumInputImageItems <= AVIF_SAMPLE_TRANSFORM_MAX_NUM_INPUT_IMAGE_ITEMS);
const avifImage * inputImages[AVIF_SAMPLE_TRANSFORM_MAX_NUM_INPUT_IMAGE_ITEMS];
for (uint32_t i = 0; i < decoder->data->sampleTransformNumInputImageItems; ++i) {
avifItemCategory category = decoder->data->sampleTransformInputImageItems[i];
if (category == AVIF_ITEM_COLOR) {
inputImages[i] = decoder->image;
} else {
AVIF_ASSERT_OR_RETURN(category >= AVIF_ITEM_SAMPLE_TRANSFORM_INPUT_0_COLOR &&
category < AVIF_ITEM_SAMPLE_TRANSFORM_INPUT_0_COLOR +
AVIF_SAMPLE_TRANSFORM_MAX_NUM_EXTRA_INPUT_IMAGE_ITEMS);
if (alpha) {
category += AVIF_SAMPLE_TRANSFORM_MAX_NUM_EXTRA_INPUT_IMAGE_ITEMS;
}
const avifTileInfo * tileInfo = &decoder->data->tileInfos[category];
AVIF_CHECKERR(tileInfo->tileCount == 1, AVIF_RESULT_NOT_IMPLEMENTED); // TODO(yguyon): Implement Sample Transform grids
inputImages[i] = decoder->data->tiles.tile[tileInfo->firstTileIndex].image;
AVIF_ASSERT_OR_RETURN(inputImages[i] != NULL);
}
}
AVIF_CHECKRES(avifImageApplyExpression(dstImage,
AVIF_SAMPLE_TRANSFORM_BIT_DEPTH_32,
&decoder->data->meta->sampleTransformExpression,
decoder->data->sampleTransformNumInputImageItems,
inputImages,
alpha ? AVIF_PLANES_A : AVIF_PLANES_YUV));
}
return AVIF_RESULT_OK;
}
#endif // AVIF_ENABLE_EXPERIMENTAL_SAMPLE_TRANSFORM
avifResult avifDecoderNextImage(avifDecoder * decoder)
{
avifDiagnosticsClearError(&decoder->diag);
if (!decoder->data || decoder->data->tiles.count == 0) {
// Nothing has been parsed yet
return AVIF_RESULT_NO_CONTENT;
}
if (!decoder->io || !decoder->io->read) {
return AVIF_RESULT_IO_NOT_SET;
}
if (avifDecoderDataFrameFullyDecoded(decoder->data)) {
// A frame was decoded during the last avifDecoderNextImage() call.
for (int c = 0; c < AVIF_ITEM_CATEGORY_COUNT; ++c) {
decoder->data->tileInfos[c].decodedTileCount = 0;
}
}
AVIF_ASSERT_OR_RETURN(decoder->data->tiles.count == (decoder->data->tileInfos[AVIF_ITEM_CATEGORY_COUNT - 1].firstTileIndex +
decoder->data->tileInfos[AVIF_ITEM_CATEGORY_COUNT - 1].tileCount));
const uint32_t nextImageIndex = (uint32_t)(decoder->imageIndex + 1);
// Ensure that we have created the codecs before proceeding with the decoding.
if (!decoder->data->tiles.tile[0].codec) {
AVIF_CHECKRES(avifDecoderCreateCodecs(decoder));
}
// Acquire all sample data for the current image first, allowing for any read call to bail out
// with AVIF_RESULT_WAITING_ON_IO harmlessly / idempotently, unless decoder->allowIncremental.
avifResult prepareTileResult[AVIF_ITEM_CATEGORY_COUNT];
for (int c = 0; c < AVIF_ITEM_CATEGORY_COUNT; ++c) {
prepareTileResult[c] = avifDecoderPrepareTiles(decoder, nextImageIndex, &decoder->data->tileInfos[c]);
if (!decoder->allowIncremental || (prepareTileResult[c] != AVIF_RESULT_WAITING_ON_IO)) {
AVIF_CHECKRES(prepareTileResult[c]);
}
}
// Decode all available color tiles now, then all available alpha tiles, then all available bit
// depth extension tiles. The order of appearance of the tiles in the bitstream is left to the
// encoder's choice, and decoding as many as possible of each category in parallel is beneficial
// for incremental decoding, as pixel rows need all channels to be decoded before being
// accessible to the user.
for (int c = 0; c < AVIF_ITEM_CATEGORY_COUNT; ++c) {
AVIF_CHECKRES(avifDecoderDecodeTiles(decoder, nextImageIndex, &decoder->data->tileInfos[c]));
}
if (!avifDecoderDataFrameFullyDecoded(decoder->data)) {
AVIF_ASSERT_OR_RETURN(decoder->allowIncremental);
// The image is not completely decoded. There should be no error unrelated to missing bytes,
// and at least some missing bytes.
avifResult firstNonOkResult = AVIF_RESULT_OK;
for (int c = 0; c < AVIF_ITEM_CATEGORY_COUNT; ++c) {
AVIF_ASSERT_OR_RETURN(prepareTileResult[c] == AVIF_RESULT_OK || prepareTileResult[c] == AVIF_RESULT_WAITING_ON_IO);
if (firstNonOkResult == AVIF_RESULT_OK) {
firstNonOkResult = prepareTileResult[c];
}
}
AVIF_ASSERT_OR_RETURN(firstNonOkResult != AVIF_RESULT_OK);
// Return the "not enough bytes" status now instead of moving on to the next frame.
return AVIF_RESULT_WAITING_ON_IO;
}
for (int c = 0; c < AVIF_ITEM_CATEGORY_COUNT; ++c) {
AVIF_ASSERT_OR_RETURN(prepareTileResult[c] == AVIF_RESULT_OK);
}
#if defined(AVIF_ENABLE_EXPERIMENTAL_SAMPLE_TRANSFORM)
if (decoder->data->meta->sampleTransformExpression.count > 0) {
// TODO(yguyon): Add a field in avifDecoder and only perform sample transformations upon request.
AVIF_CHECKRES(avifDecoderApplySampleTransform(decoder, decoder->image));
}
#endif // AVIF_ENABLE_EXPERIMENTAL_SAMPLE_TRANSFORM
// Only advance decoder->imageIndex once the image is completely decoded, so that
// avifDecoderNthImage(decoder, decoder->imageIndex + 1) is equivalent to avifDecoderNextImage(decoder)
// if the previous call to avifDecoderNextImage() returned AVIF_RESULT_WAITING_ON_IO.
decoder->imageIndex = (int)nextImageIndex;
// The decoded tile counts will be reset to 0 the next time avifDecoderNextImage() is called,
// for avifDecoderDecodedRowCount() to work until then.
if (decoder->data->sourceSampleTable) {
// Decoding from a track! Provide timing information.
avifResult timingResult = avifDecoderNthImageTiming(decoder, decoder->imageIndex, &decoder->imageTiming);
if (timingResult != AVIF_RESULT_OK) {
return timingResult;
}
}
return AVIF_RESULT_OK;
}
avifResult avifDecoderNthImageTiming(const avifDecoder * decoder, uint32_t frameIndex, avifImageTiming * outTiming)
{
if (!decoder->data) {
// Nothing has been parsed yet
return AVIF_RESULT_NO_CONTENT;
}
if ((frameIndex > INT_MAX) || ((int)frameIndex >= decoder->imageCount)) {
// Impossible index
return AVIF_RESULT_NO_IMAGES_REMAINING;
}
if (!decoder->data->sourceSampleTable) {
// There isn't any real timing associated with this decode, so
// just hand back the defaults chosen in avifDecoderReset().
*outTiming = decoder->imageTiming;
return AVIF_RESULT_OK;
}
outTiming->timescale = decoder->timescale;
outTiming->ptsInTimescales = 0;
for (int imageIndex = 0; imageIndex < (int)frameIndex; ++imageIndex) {
outTiming->ptsInTimescales += avifSampleTableGetImageDelta(decoder->data->sourceSampleTable, imageIndex);
}
outTiming->durationInTimescales = avifSampleTableGetImageDelta(decoder->data->sourceSampleTable, frameIndex);
if (outTiming->timescale > 0) {
outTiming->pts = (double)outTiming->ptsInTimescales / (double)outTiming->timescale;
outTiming->duration = (double)outTiming->durationInTimescales / (double)outTiming->timescale;
} else {
outTiming->pts = 0.0;
outTiming->duration = 0.0;
}
return AVIF_RESULT_OK;
}
avifResult avifDecoderNthImage(avifDecoder * decoder, uint32_t frameIndex)
{
avifDiagnosticsClearError(&decoder->diag);
if (!decoder->data) {
// Nothing has been parsed yet
return AVIF_RESULT_NO_CONTENT;
}
if ((frameIndex > INT_MAX) || ((int)frameIndex >= decoder->imageCount)) {
// Impossible index
return AVIF_RESULT_NO_IMAGES_REMAINING;
}
int requestedIndex = (int)frameIndex;
if (requestedIndex == (decoder->imageIndex + 1)) {
// It's just the next image (already partially decoded or not at all), nothing special here
return avifDecoderNextImage(decoder);
}
if (requestedIndex == decoder->imageIndex) {
if (avifDecoderDataFrameFullyDecoded(decoder->data)) {
// The current fully decoded image (decoder->imageIndex) is requested, nothing to do
return AVIF_RESULT_OK;
}
// The next image (decoder->imageIndex + 1) is partially decoded but
// the previous image (decoder->imageIndex) is requested.
// Fall through to resetting the decoder data and start decoding from
// the nearest key frame.
}
int nearestKeyFrame = (int)avifDecoderNearestKeyframe(decoder, frameIndex);
if ((nearestKeyFrame > (decoder->imageIndex + 1)) || (requestedIndex <= decoder->imageIndex)) {
// If we get here, we need to start decoding from the nearest key frame.
// So discard the unused decoder state and its previous frames. This
// will force the setup of new AV1 decoder (avifCodec) instances in
// avifDecoderNextImage().
decoder->imageIndex = nearestKeyFrame - 1; // prepare to read nearest keyframe
avifDecoderDataResetCodec(decoder->data);
}
for (;;) {
avifResult result = avifDecoderNextImage(decoder);
if (result != AVIF_RESULT_OK) {
return result;
}
if (requestedIndex == decoder->imageIndex) {
break;
}
}
return AVIF_RESULT_OK;
}
avifBool avifDecoderIsKeyframe(const avifDecoder * decoder, uint32_t frameIndex)
{
if (!decoder->data || (decoder->data->tiles.count == 0)) {
// Nothing has been parsed yet
return AVIF_FALSE;
}
// *All* tiles for the requested frameIndex must be keyframes in order for
// avifDecoderIsKeyframe() to return true, otherwise we may seek to a frame in which the color
// planes are a keyframe but the alpha plane isn't a keyframe, which will cause an alpha plane
// decode failure.
for (unsigned int i = 0; i < decoder->data->tiles.count; ++i) {
const avifTile * tile = &decoder->data->tiles.tile[i];
if ((frameIndex >= tile->input->samples.count) || !tile->input->samples.sample[frameIndex].sync) {
return AVIF_FALSE;
}
}
return AVIF_TRUE;
}
uint32_t avifDecoderNearestKeyframe(const avifDecoder * decoder, uint32_t frameIndex)
{
if (!decoder->data) {
// Nothing has been parsed yet
return 0;
}
for (; frameIndex != 0; --frameIndex) {
if (avifDecoderIsKeyframe(decoder, frameIndex)) {
break;
}
}
return frameIndex;
}
// Returns the number of available rows in decoder->image given a color or alpha subimage.
static uint32_t avifGetDecodedRowCount(const avifDecoder * decoder, const avifTileInfo * info, const avifImage * image)
{
if (info->decodedTileCount == info->tileCount) {
return image->height;
}
if (info->decodedTileCount == 0) {
return 0;
}
#if defined(AVIF_ENABLE_EXPERIMENTAL_SAMPLE_TRANSFORM)
if (decoder->data->meta->sampleTransformExpression.count > 0) {
// TODO(yguyon): Support incremental Sample Transforms
return 0;
}
#endif
if ((info->grid.rows > 0) && (info->grid.columns > 0)) {
// Grid of AVIF tiles (not to be confused with AV1 tiles).
const uint32_t tileHeight = decoder->data->tiles.tile[info->firstTileIndex].height;
return AVIF_MIN((info->decodedTileCount / info->grid.columns) * tileHeight, image->height);
} else {
// Non-grid image.
return image->height;
}
}
uint32_t avifDecoderDecodedRowCount(const avifDecoder * decoder)
{
uint32_t minRowCount = decoder->image->height;
for (int c = 0; c < AVIF_ITEM_CATEGORY_COUNT; ++c) {
#if defined(AVIF_ENABLE_EXPERIMENTAL_GAIN_MAP)
if (c == AVIF_ITEM_GAIN_MAP) {
const avifImage * const gainMap = decoder->image->gainMap ? decoder->image->gainMap->image : NULL;
if (decoder->gainMapPresent && decoder->enableDecodingGainMap && gainMap != NULL && gainMap->height != 0) {
uint32_t gainMapRowCount = avifGetDecodedRowCount(decoder, &decoder->data->tileInfos[AVIF_ITEM_GAIN_MAP], gainMap);
if (gainMap->height != decoder->image->height) {
const uint32_t scaledGainMapRowCount =
(uint32_t)floorf((float)gainMapRowCount / gainMap->height * decoder->image->height);
// Make sure it matches the formula described in the comment of avifDecoderDecodedRowCount() in avif.h.
AVIF_CHECKERR((uint32_t)lround((double)scaledGainMapRowCount / decoder->image->height *
decoder->image->gainMap->image->height) <= gainMapRowCount,
0);
gainMapRowCount = scaledGainMapRowCount;
}
minRowCount = AVIF_MIN(minRowCount, gainMapRowCount);
}
continue;
}
#endif
const uint32_t rowCount = avifGetDecodedRowCount(decoder, &decoder->data->tileInfos[c], decoder->image);
minRowCount = AVIF_MIN(minRowCount, rowCount);
}
return minRowCount;
}
avifResult avifDecoderRead(avifDecoder * decoder, avifImage * image)
{
avifResult result = avifDecoderParse(decoder);
if (result != AVIF_RESULT_OK) {
return result;
}
result = avifDecoderNextImage(decoder);
if (result != AVIF_RESULT_OK) {
return result;
}
// If decoder->image->imageOwnsYUVPlanes is true and decoder->image is not used after this call,
// the ownership of the planes in decoder->image could be transferred here instead of copied.
// However most codec_*.c implementations allocate the output buffer themselves and return a
// view, unless some postprocessing is applied (container-level grid reconstruction for
// example), so the first condition rarely holds.
// The second condition does not hold either: it is not required by the documentation in avif.h.
return avifImageCopy(image, decoder->image, AVIF_PLANES_ALL);
}
avifResult avifDecoderReadMemory(avifDecoder * decoder, avifImage * image, const uint8_t * data, size_t size)
{
avifDiagnosticsClearError(&decoder->diag);
avifResult result = avifDecoderSetIOMemory(decoder, data, size);
if (result != AVIF_RESULT_OK) {
return result;
}
return avifDecoderRead(decoder, image);
}
avifResult avifDecoderReadFile(avifDecoder * decoder, avifImage * image, const char * filename)
{
avifDiagnosticsClearError(&decoder->diag);
avifResult result = avifDecoderSetIOFile(decoder, filename);
if (result != AVIF_RESULT_OK) {
return result;
}
return avifDecoderRead(decoder, image);
}