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aomedia / libavif / 6b0a47b53604d8cdd8f44dcf7bc4bc69fb5fa6f5 / . / src / write.c
blob: 5d54ca625a74e87de2aec30c0dbd46986e862d5e [file] [log] [blame]
// Copyright 2019 Joe Drago. All rights reserved.
// SPDX-License-Identifier: BSD-2-Clause
#include "avif/internal.h"
#include <assert.h>
#include <string.h>
#include <time.h>
#define MAX_ASSOCIATIONS 16
struct ipmaArray
{
uint8_t associations[MAX_ASSOCIATIONS];
avifBool essential[MAX_ASSOCIATIONS];
uint8_t count;
};
// Used to store offsets in meta boxes which need to point at mdat offsets that
// aren't known yet. When an item's mdat payload is written, all registered fixups
// will have this now-known offset "fixed up".
typedef struct avifOffsetFixup
{
size_t offset;
} avifOffsetFixup;
AVIF_ARRAY_DECLARE(avifOffsetFixupArray, avifOffsetFixup, fixup);
static const char alphaURN[] = AVIF_URN_ALPHA0;
static const size_t alphaURNSize = sizeof(alphaURN);
static const char xmpContentType[] = AVIF_CONTENT_TYPE_XMP;
static const size_t xmpContentTypeSize = sizeof(xmpContentType);
static avifResult writeCodecConfig(avifRWStream * s, const avifCodecConfigurationBox * cfg);
static avifResult writeConfigBox(avifRWStream * s, const avifCodecConfigurationBox * cfg, const char * configPropName);
// ---------------------------------------------------------------------------
// avifSetTileConfiguration
static int floorLog2(uint32_t n)
{
assert(n > 0);
int count = 0;
while (n != 0) {
++count;
n >>= 1;
}
return count - 1;
}
// Splits tilesLog2 into *tileDim1Log2 and *tileDim2Log2, considering the ratio of dim1 to dim2.
//
// Precondition:
// dim1 >= dim2
// Postcondition:
// tilesLog2 == *tileDim1Log2 + *tileDim2Log2
// *tileDim1Log2 >= *tileDim2Log2
static void splitTilesLog2(uint32_t dim1, uint32_t dim2, int tilesLog2, int * tileDim1Log2, int * tileDim2Log2)
{
assert(dim1 >= dim2);
uint32_t ratio = dim1 / dim2;
int diffLog2 = floorLog2(ratio);
int subtract = tilesLog2 - diffLog2;
if (subtract < 0) {
subtract = 0;
}
*tileDim2Log2 = subtract / 2;
*tileDim1Log2 = tilesLog2 - *tileDim2Log2;
assert(*tileDim1Log2 >= *tileDim2Log2);
}
// Set the tile configuration: the number of tiles and the tile size.
//
// Tiles improve encoding and decoding speeds when multiple threads are available. However, for
// image coding, the total tile boundary length affects the compression efficiency because intra
// prediction can't go across tile boundaries. So the more tiles there are in an image, the worse
// the compression ratio is. For a given number of tiles, making the tile size close to a square
// tends to reduce the total tile boundary length inside the image. Use more tiles along the longer
// dimension of the image to make the tile size closer to a square.
void avifSetTileConfiguration(int threads, uint32_t width, uint32_t height, int * tileRowsLog2, int * tileColsLog2)
{
*tileRowsLog2 = 0;
*tileColsLog2 = 0;
if (threads > 1) {
// Avoid small tiles because they are particularly bad for image coding.
//
// Use no more tiles than the number of threads. Aim for one tile per thread. Using more
// than one thread inside one tile could be less efficient. Using more tiles than the
// number of threads would result in a compression penalty without much benefit.
const uint32_t kMinTileArea = 512 * 512;
const uint32_t kMaxTiles = 32;
uint32_t imageArea = width * height;
uint32_t tiles = (imageArea + kMinTileArea - 1) / kMinTileArea;
if (tiles > kMaxTiles) {
tiles = kMaxTiles;
}
if (tiles > (uint32_t)threads) {
tiles = threads;
}
int tilesLog2 = floorLog2(tiles);
// If the image's width is greater than the height, use more tile columns than tile rows.
if (width >= height) {
splitTilesLog2(width, height, tilesLog2, tileColsLog2, tileRowsLog2);
} else {
splitTilesLog2(height, width, tilesLog2, tileRowsLog2, tileColsLog2);
}
}
}
// ---------------------------------------------------------------------------
// avifCodecEncodeOutput
avifCodecEncodeOutput * avifCodecEncodeOutputCreate(void)
{
avifCodecEncodeOutput * encodeOutput = (avifCodecEncodeOutput *)avifAlloc(sizeof(avifCodecEncodeOutput));
if (encodeOutput == NULL) {
return NULL;
}
memset(encodeOutput, 0, sizeof(avifCodecEncodeOutput));
if (!avifArrayCreate(&encodeOutput->samples, sizeof(avifEncodeSample), 1)) {
avifCodecEncodeOutputDestroy(encodeOutput);
return NULL;
}
return encodeOutput;
}
avifResult avifCodecEncodeOutputAddSample(avifCodecEncodeOutput * encodeOutput, const uint8_t * data, size_t len, avifBool sync)
{
avifEncodeSample * sample = (avifEncodeSample *)avifArrayPush(&encodeOutput->samples);
AVIF_CHECKERR(sample, AVIF_RESULT_OUT_OF_MEMORY);
const avifResult result = avifRWDataSet(&sample->data, data, len);
if (result != AVIF_RESULT_OK) {
avifArrayPop(&encodeOutput->samples);
return result;
}
sample->sync = sync;
return AVIF_RESULT_OK;
}
void avifCodecEncodeOutputDestroy(avifCodecEncodeOutput * encodeOutput)
{
for (uint32_t sampleIndex = 0; sampleIndex < encodeOutput->samples.count; ++sampleIndex) {
avifRWDataFree(&encodeOutput->samples.sample[sampleIndex].data);
}
avifArrayDestroy(&encodeOutput->samples);
avifFree(encodeOutput);
}
// ---------------------------------------------------------------------------
// avifEncoderItem
// one "item" worth for encoder
typedef struct avifEncoderItem
{
uint16_t id;
uint8_t type[4]; // 4-character 'item_type' field in the 'infe' (item info entry) box
avifCodec * codec; // only present on image items
avifCodecEncodeOutput * encodeOutput; // AV1 sample data
avifRWData metadataPayload; // Exif/XMP data
avifCodecConfigurationBox av1C; // Harvested in avifEncoderFinish(), if encodeOutput has samples
// TODO(yguyon): Rename or add av2C
uint32_t cellIndex; // Which row-major cell index corresponds to this item. only present on image items
avifItemCategory itemCategory; // Category of item being encoded
avifBool hiddenImage; // A hidden image item has (flags & 1) equal to 1 in its ItemInfoEntry.
const char * infeName;
size_t infeNameSize;
const char * infeContentType;
size_t infeContentTypeSize;
avifOffsetFixupArray mdatFixups;
uint16_t irefToID; // if non-zero, make an iref from this id -> irefToID
const char * irefType;
uint32_t gridCols; // if non-zero (legal range [1-256]), this is a grid item
uint32_t gridRows; // if non-zero (legal range [1-256]), this is a grid item
// the reconstructed image of a grid item will be trimmed to these dimensions (only present on grid items)
uint32_t gridWidth;
uint32_t gridHeight;
uint32_t extraLayerCount; // if non-zero (legal range [1-(AVIF_MAX_AV1_LAYER_COUNT-1)]), this is a layered AV1 image
uint16_t dimgFromID; // if non-zero, make an iref from dimgFromID -> this id
struct ipmaArray ipma;
} avifEncoderItem;
AVIF_ARRAY_DECLARE(avifEncoderItemArray, avifEncoderItem, item);
// ---------------------------------------------------------------------------
// avifEncoderItemReference
// pointer to one "item" interested in
typedef avifEncoderItem * avifEncoderItemReference;
AVIF_ARRAY_DECLARE(avifEncoderItemReferenceArray, avifEncoderItemReference, ref);
// ---------------------------------------------------------------------------
// avifEncoderFrame
typedef struct avifEncoderFrame
{
uint64_t durationInTimescales;
} avifEncoderFrame;
AVIF_ARRAY_DECLARE(avifEncoderFrameArray, avifEncoderFrame, frame);
// ---------------------------------------------------------------------------
// avifEncoderData
AVIF_ARRAY_DECLARE(avifEncoderItemIdArray, uint16_t, item_id);
typedef struct avifEncoderData
{
avifEncoderItemArray items;
avifEncoderFrameArray frames;
// Map the encoder settings quality and qualityAlpha to quantizer and quantizerAlpha
int quantizer;
int quantizerAlpha;
#if defined(AVIF_ENABLE_EXPERIMENTAL_GAIN_MAP)
int quantizerGainMap;
#endif
// tileRowsLog2 and tileColsLog2 are the actual tiling values after automatic tiling is handled
int tileRowsLog2;
int tileColsLog2;
avifEncoder lastEncoder;
// lastQuantizer and lastQuantizerAlpha are the quantizer and quantizerAlpha values used last
// time
int lastQuantizer;
int lastQuantizerAlpha;
// lastTileRowsLog2 and lastTileColsLog2 are the actual tiling values used last time
int lastTileRowsLog2;
int lastTileColsLog2;
avifImage * imageMetadata;
#if defined(AVIF_ENABLE_EXPERIMENTAL_GAIN_MAP)
// For convenience, holds metadata derived from the avifGainMap struct (when present) about the
// altenate image
avifImage * altImageMetadata;
#endif
uint16_t lastItemID;
uint16_t primaryItemID;
avifEncoderItemIdArray alternativeItemIDs; // list of item ids for an 'altr' box (group of alternatives to each other)
avifBool singleImage; // if true, the AVIF_ADD_IMAGE_FLAG_SINGLE flag was set on the first call to avifEncoderAddImage()
avifBool alphaPresent;
size_t gainMapSizeBytes;
// Fields specific to AV1/AV2
const char * imageItemType; // "av01" for AV1 ("av02" for AV2 if AVIF_CODEC_AVM)
const char * configPropName; // "av1C" for AV1 ("av2C" for AV2 if AVIF_CODEC_AVM)
} avifEncoderData;
static void avifEncoderDataDestroy(avifEncoderData * data);
// Returns NULL if a memory allocation failed.
static avifEncoderData * avifEncoderDataCreate(void)
{
avifEncoderData * data = (avifEncoderData *)avifAlloc(sizeof(avifEncoderData));
if (!data) {
return NULL;
}
memset(data, 0, sizeof(avifEncoderData));
data->imageMetadata = avifImageCreateEmpty();
if (!data->imageMetadata) {
goto error;
}
#if defined(AVIF_ENABLE_EXPERIMENTAL_GAIN_MAP)
data->altImageMetadata = avifImageCreateEmpty();
if (!data->altImageMetadata) {
goto error;
}
#endif
if (!avifArrayCreate(&data->items, sizeof(avifEncoderItem), 8)) {
goto error;
}
if (!avifArrayCreate(&data->frames, sizeof(avifEncoderFrame), 1)) {
goto error;
}
if (!avifArrayCreate(&data->alternativeItemIDs, sizeof(uint16_t), 1)) {
goto error;
}
return data;
error:
avifEncoderDataDestroy(data);
return NULL;
}
static avifEncoderItem * avifEncoderDataCreateItem(avifEncoderData * data, const char * type, const char * infeName, size_t infeNameSize, uint32_t cellIndex)
{
avifEncoderItem * item = (avifEncoderItem *)avifArrayPush(&data->items);
if (item == NULL) {
return NULL;
}
++data->lastItemID;
item->id = data->lastItemID;
memcpy(item->type, type, sizeof(item->type));
item->infeName = infeName;
item->infeNameSize = infeNameSize;
item->encodeOutput = avifCodecEncodeOutputCreate();
if (item->encodeOutput == NULL) {
goto error;
}
item->cellIndex = cellIndex;
if (!avifArrayCreate(&item->mdatFixups, sizeof(avifOffsetFixup), 4)) {
goto error;
}
return item;
error:
if (item->encodeOutput != NULL) {
avifCodecEncodeOutputDestroy(item->encodeOutput);
}
--data->lastItemID;
avifArrayPop(&data->items);
return NULL;
}
static avifEncoderItem * avifEncoderDataFindItemByID(avifEncoderData * data, uint16_t id)
{
for (uint32_t itemIndex = 0; itemIndex < data->items.count; ++itemIndex) {
avifEncoderItem * item = &data->items.item[itemIndex];
if (item->id == id) {
return item;
}
}
return NULL;
}
static void avifEncoderDataDestroy(avifEncoderData * data)
{
for (uint32_t i = 0; i < data->items.count; ++i) {
avifEncoderItem * item = &data->items.item[i];
if (item->codec) {
avifCodecDestroy(item->codec);
}
avifCodecEncodeOutputDestroy(item->encodeOutput);
avifRWDataFree(&item->metadataPayload);
avifArrayDestroy(&item->mdatFixups);
}
if (data->imageMetadata) {
avifImageDestroy(data->imageMetadata);
}
#if defined(AVIF_ENABLE_EXPERIMENTAL_GAIN_MAP)
if (data->altImageMetadata) {
avifImageDestroy(data->altImageMetadata);
}
#endif
avifArrayDestroy(&data->items);
avifArrayDestroy(&data->frames);
avifArrayDestroy(&data->alternativeItemIDs);
avifFree(data);
}
static avifResult avifEncoderItemAddMdatFixup(avifEncoderItem * item, const avifRWStream * s)
{
avifOffsetFixup * fixup = (avifOffsetFixup *)avifArrayPush(&item->mdatFixups);
AVIF_CHECKERR(fixup != NULL, AVIF_RESULT_OUT_OF_MEMORY);
fixup->offset = avifRWStreamOffset(s);
return AVIF_RESULT_OK;
}
// ---------------------------------------------------------------------------
// avifItemPropertyDedup - Provides ipco deduplication
typedef struct avifItemProperty
{
uint8_t index;
size_t offset;
size_t size;
} avifItemProperty;
AVIF_ARRAY_DECLARE(avifItemPropertyArray, avifItemProperty, property);
typedef struct avifItemPropertyDedup
{
avifItemPropertyArray properties;
avifRWStream s; // Temporary stream for each new property, checked against already-written boxes for deduplications
avifRWData buffer; // Temporary storage for 's'
uint8_t nextIndex; // 1-indexed, incremented every time another unique property is finished
} avifItemPropertyDedup;
static avifItemPropertyDedup * avifItemPropertyDedupCreate(void)
{
avifItemPropertyDedup * dedup = (avifItemPropertyDedup *)avifAlloc(sizeof(avifItemPropertyDedup));
if (dedup == NULL) {
return NULL;
}
memset(dedup, 0, sizeof(avifItemPropertyDedup));
if (!avifArrayCreate(&dedup->properties, sizeof(avifItemProperty), 8)) {
avifFree(dedup);
return NULL;
}
if (avifRWDataRealloc(&dedup->buffer, 2048) != AVIF_RESULT_OK) {
avifArrayDestroy(&dedup->properties);
avifFree(dedup);
return NULL;
}
return dedup;
}
static void avifItemPropertyDedupDestroy(avifItemPropertyDedup * dedup)
{
avifArrayDestroy(&dedup->properties);
avifRWDataFree(&dedup->buffer);
avifFree(dedup);
}
// Resets the dedup's temporary write stream in preparation for a single item property's worth of writing
static void avifItemPropertyDedupStart(avifItemPropertyDedup * dedup)
{
avifRWStreamStart(&dedup->s, &dedup->buffer);
}
// This compares the newly written item property (in the dedup's temporary storage buffer) to
// already-written properties (whose offsets/sizes in outputStream are recorded in the dedup). If a
// match is found, the previous property's index is used. If this new property is unique, it is
// assigned the next available property index, written to the output stream, and its offset/size in
// the output stream is recorded in the dedup for future comparisons.
//
// On success, this function adds to the given ipma box a property association linking the reused
// or newly created property with the item.
static avifResult avifItemPropertyDedupFinish(avifItemPropertyDedup * dedup, avifRWStream * outputStream, struct ipmaArray * ipma, avifBool essential)
{
uint8_t propertyIndex = 0;
const size_t newPropertySize = avifRWStreamOffset(&dedup->s);
for (size_t i = 0; i < dedup->properties.count; ++i) {
avifItemProperty * property = &dedup->properties.property[i];
if ((property->size == newPropertySize) &&
!memcmp(&outputStream->raw->data[property->offset], dedup->buffer.data, newPropertySize)) {
// We've already written this exact property, reuse it
propertyIndex = property->index;
AVIF_ASSERT_OR_RETURN(propertyIndex != 0);
break;
}
}
if (propertyIndex == 0) {
// Write a new property, and remember its location in the output stream for future deduplication
avifItemProperty * property = (avifItemProperty *)avifArrayPush(&dedup->properties);
AVIF_CHECKERR(property != NULL, AVIF_RESULT_OUT_OF_MEMORY);
property->index = ++dedup->nextIndex; // preincrement so the first new index is 1 (as ipma is 1-indexed)
property->size = newPropertySize;
property->offset = avifRWStreamOffset(outputStream);
AVIF_CHECKRES(avifRWStreamWrite(outputStream, dedup->buffer.data, newPropertySize));
propertyIndex = property->index;
}
AVIF_CHECKERR(ipma->count < MAX_ASSOCIATIONS, AVIF_RESULT_UNKNOWN_ERROR);
ipma->associations[ipma->count] = propertyIndex;
ipma->essential[ipma->count] = essential;
++ipma->count;
return AVIF_RESULT_OK;
}
// ---------------------------------------------------------------------------
static const avifScalingMode noScaling = { { 1, 1 }, { 1, 1 } };
avifEncoder * avifEncoderCreate(void)
{
avifEncoder * encoder = (avifEncoder *)avifAlloc(sizeof(avifEncoder));
if (!encoder) {
return NULL;
}
memset(encoder, 0, sizeof(avifEncoder));
encoder->codecChoice = AVIF_CODEC_CHOICE_AUTO;
encoder->maxThreads = 1;
encoder->speed = AVIF_SPEED_DEFAULT;
encoder->keyframeInterval = 0;
encoder->timescale = 1;
encoder->repetitionCount = AVIF_REPETITION_COUNT_INFINITE;
encoder->quality = AVIF_QUALITY_DEFAULT;
encoder->qualityAlpha = AVIF_QUALITY_DEFAULT;
#if defined(AVIF_ENABLE_EXPERIMENTAL_GAIN_MAP)
encoder->qualityGainMap = AVIF_QUALITY_DEFAULT;
#endif
encoder->minQuantizer = AVIF_QUANTIZER_BEST_QUALITY;
encoder->maxQuantizer = AVIF_QUANTIZER_WORST_QUALITY;
encoder->minQuantizerAlpha = AVIF_QUANTIZER_BEST_QUALITY;
encoder->maxQuantizerAlpha = AVIF_QUANTIZER_WORST_QUALITY;
encoder->tileRowsLog2 = 0;
encoder->tileColsLog2 = 0;
encoder->autoTiling = AVIF_FALSE;
encoder->scalingMode = noScaling;
encoder->data = avifEncoderDataCreate();
encoder->csOptions = avifCodecSpecificOptionsCreate();
if (!encoder->data || !encoder->csOptions) {
avifEncoderDestroy(encoder);
return NULL;
}
encoder->headerFormat = AVIF_HEADER_FULL;
#if defined(AVIF_ENABLE_EXPERIMENTAL_SAMPLE_TRANSFORM)
encoder->sampleTransformRecipe = AVIF_SAMPLE_TRANSFORM_NONE;
#endif
return encoder;
}
void avifEncoderDestroy(avifEncoder * encoder)
{
if (encoder->csOptions) {
avifCodecSpecificOptionsDestroy(encoder->csOptions);
}
if (encoder->data) {
avifEncoderDataDestroy(encoder->data);
}
avifFree(encoder);
}
avifResult avifEncoderSetCodecSpecificOption(avifEncoder * encoder, const char * key, const char * value)
{
return avifCodecSpecificOptionsSet(encoder->csOptions, key, value);
}
static void avifEncoderBackupSettings(avifEncoder * encoder)
{
avifEncoder * lastEncoder = &encoder->data->lastEncoder;
// lastEncoder->data is only used to mark that lastEncoder is initialized. lastEncoder->data
// must not be dereferenced.
lastEncoder->data = encoder->data;
lastEncoder->codecChoice = encoder->codecChoice;
lastEncoder->maxThreads = encoder->maxThreads;
lastEncoder->speed = encoder->speed;
lastEncoder->keyframeInterval = encoder->keyframeInterval;
lastEncoder->timescale = encoder->timescale;
lastEncoder->repetitionCount = encoder->repetitionCount;
lastEncoder->extraLayerCount = encoder->extraLayerCount;
lastEncoder->minQuantizer = encoder->minQuantizer;
lastEncoder->maxQuantizer = encoder->maxQuantizer;
lastEncoder->minQuantizerAlpha = encoder->minQuantizerAlpha;
lastEncoder->maxQuantizerAlpha = encoder->maxQuantizerAlpha;
encoder->data->lastQuantizer = encoder->data->quantizer;
encoder->data->lastQuantizerAlpha = encoder->data->quantizerAlpha;
encoder->data->lastTileRowsLog2 = encoder->data->tileRowsLog2;
encoder->data->lastTileColsLog2 = encoder->data->tileColsLog2;
lastEncoder->scalingMode = encoder->scalingMode;
#if defined(AVIF_ENABLE_EXPERIMENTAL_SAMPLE_TRANSFORM)
lastEncoder->sampleTransformRecipe = encoder->sampleTransformRecipe;
#endif
}
// This function detects changes made on avifEncoder. It returns true on success (i.e., if every
// change is valid), or false on failure (i.e., if any setting that can't change was changed). It
// reports a bitwise-OR of detected changes in encoderChanges.
static avifBool avifEncoderDetectChanges(const avifEncoder * encoder, avifEncoderChanges * encoderChanges)
{
const avifEncoder * lastEncoder = &encoder->data->lastEncoder;
*encoderChanges = 0;
if (!lastEncoder->data) {
// lastEncoder is not initialized.
return AVIF_TRUE;
}
if ((lastEncoder->codecChoice != encoder->codecChoice) || (lastEncoder->maxThreads != encoder->maxThreads) ||
(lastEncoder->speed != encoder->speed) || (lastEncoder->keyframeInterval != encoder->keyframeInterval) ||
(lastEncoder->timescale != encoder->timescale) || (lastEncoder->repetitionCount != encoder->repetitionCount) ||
(lastEncoder->extraLayerCount != encoder->extraLayerCount)) {
return AVIF_FALSE;
}
if (encoder->data->lastQuantizer != encoder->data->quantizer) {
*encoderChanges |= AVIF_ENCODER_CHANGE_QUANTIZER;
}
if (encoder->data->lastQuantizerAlpha != encoder->data->quantizerAlpha) {
*encoderChanges |= AVIF_ENCODER_CHANGE_QUANTIZER_ALPHA;
}
if (lastEncoder->minQuantizer != encoder->minQuantizer) {
*encoderChanges |= AVIF_ENCODER_CHANGE_MIN_QUANTIZER;
}
if (lastEncoder->maxQuantizer != encoder->maxQuantizer) {
*encoderChanges |= AVIF_ENCODER_CHANGE_MAX_QUANTIZER;
}
if (lastEncoder->minQuantizerAlpha != encoder->minQuantizerAlpha) {
*encoderChanges |= AVIF_ENCODER_CHANGE_MIN_QUANTIZER_ALPHA;
}
if (lastEncoder->maxQuantizerAlpha != encoder->maxQuantizerAlpha) {
*encoderChanges |= AVIF_ENCODER_CHANGE_MAX_QUANTIZER_ALPHA;
}
if (encoder->data->lastTileRowsLog2 != encoder->data->tileRowsLog2) {
*encoderChanges |= AVIF_ENCODER_CHANGE_TILE_ROWS_LOG2;
}
if (encoder->data->lastTileColsLog2 != encoder->data->tileColsLog2) {
*encoderChanges |= AVIF_ENCODER_CHANGE_TILE_COLS_LOG2;
}
if (memcmp(&lastEncoder->scalingMode, &encoder->scalingMode, sizeof(avifScalingMode)) != 0) {
*encoderChanges |= AVIF_ENCODER_CHANGE_SCALING_MODE;
}
if (encoder->csOptions->count > 0) {
*encoderChanges |= AVIF_ENCODER_CHANGE_CODEC_SPECIFIC;
}
#if defined(AVIF_ENABLE_EXPERIMENTAL_SAMPLE_TRANSFORM)
if (lastEncoder->sampleTransformRecipe != encoder->sampleTransformRecipe) {
return AVIF_FALSE;
}
#endif
return AVIF_TRUE;
}
// Same as 'avifEncoderWriteColorProperties' but for the colr nclx box only.
static avifResult avifEncoderWriteNclxProperty(avifRWStream * dedupStream,
avifRWStream * outputStream,
const avifImage * imageMetadata,
struct ipmaArray * ipma,
avifItemPropertyDedup * dedup)
{
if (dedup) {
avifItemPropertyDedupStart(dedup);
}
avifBoxMarker colr;
AVIF_CHECKRES(avifRWStreamWriteBox(dedupStream, "colr", AVIF_BOX_SIZE_TBD, &colr));
AVIF_CHECKRES(avifRWStreamWriteChars(dedupStream, "nclx", 4)); // unsigned int(32) colour_type;
AVIF_CHECKRES(avifRWStreamWriteU16(dedupStream, imageMetadata->colorPrimaries)); // unsigned int(16) colour_primaries;
AVIF_CHECKRES(avifRWStreamWriteU16(dedupStream, imageMetadata->transferCharacteristics)); // unsigned int(16) transfer_characteristics;
AVIF_CHECKRES(avifRWStreamWriteU16(dedupStream, imageMetadata->matrixCoefficients)); // unsigned int(16) matrix_coefficients;
AVIF_CHECKRES(avifRWStreamWriteBits(dedupStream, (imageMetadata->yuvRange == AVIF_RANGE_FULL) ? 1 : 0, /*bitCount=*/1)); // unsigned int(1) full_range_flag;
AVIF_CHECKRES(avifRWStreamWriteBits(dedupStream, 0, /*bitCount=*/7)); // unsigned int(7) reserved = 0;
avifRWStreamFinishBox(dedupStream, colr);
if (dedup) {
AVIF_CHECKRES(avifItemPropertyDedupFinish(dedup, outputStream, ipma, AVIF_FALSE));
}
return AVIF_RESULT_OK;
}
// Subset of avifEncoderWriteColorProperties() for the properties pasp, clap, irot, imir.
static avifResult avifEncoderWriteExtendedColorProperties(avifRWStream * dedupStream,
avifRWStream * outputStream,
const avifImage * imageMetadata,
struct ipmaArray * ipma,
avifItemPropertyDedup * dedup);
// This function is used in two codepaths:
// * writing color *item* properties
// * writing color *track* properties
//
// Item properties must have property associations with them and can be deduplicated (by reusing
// these associations), so this function leverages the ipma and dedup arguments to do this.
//
// Track properties, however, are implicitly associated by the track in which they are contained, so
// there is no need to build a property association box (ipma), and no way to deduplicate/reuse a
// property. In this case, the ipma and dedup properties should/will be set to NULL, and this
// function will avoid using them.
static avifResult avifEncoderWriteColorProperties(avifRWStream * outputStream,
const avifImage * imageMetadata,
struct ipmaArray * ipma,
avifItemPropertyDedup * dedup)
{
// outputStream is the final bitstream that will be output by the libavif encoder API.
// dedupStream is either equal to outputStream or to &dedup->s which is a temporary stream used
// to store parts of the final bitstream; these parts may be discarded if they are a duplicate
// of an already stored property.
avifRWStream * dedupStream = outputStream;
if (dedup) {
AVIF_ASSERT_OR_RETURN(ipma);
// Use the dedup's temporary stream for box writes.
dedupStream = &dedup->s;
}
if (imageMetadata->icc.size > 0) {
if (dedup) {
avifItemPropertyDedupStart(dedup);
}
avifBoxMarker colr;
AVIF_CHECKRES(avifRWStreamWriteBox(dedupStream, "colr", AVIF_BOX_SIZE_TBD, &colr));
AVIF_CHECKRES(avifRWStreamWriteChars(dedupStream, "prof", 4)); // unsigned int(32) colour_type;
AVIF_CHECKRES(avifRWStreamWrite(dedupStream, imageMetadata->icc.data, imageMetadata->icc.size));
avifRWStreamFinishBox(dedupStream, colr);
if (dedup) {
AVIF_CHECKRES(avifItemPropertyDedupFinish(dedup, outputStream, ipma, AVIF_FALSE));
}
}
// HEIF 6.5.5.1, from Amendment 3 allows multiple colr boxes: "at most one for a given value of colour type"
// Therefore, *always* writing an nclx box, even if an a prof box was already written above.
AVIF_CHECKRES(avifEncoderWriteNclxProperty(dedupStream, outputStream, imageMetadata, ipma, dedup));
return avifEncoderWriteExtendedColorProperties(dedupStream, outputStream, imageMetadata, ipma, dedup);
}
// Same as 'avifEncoderWriteColorProperties' but for properties related to High Dynamic Range only.
static avifResult avifEncoderWriteHDRProperties(avifRWStream * dedupStream,
avifRWStream * outputStream,
const avifImage * imageMetadata,
struct ipmaArray * ipma,
avifItemPropertyDedup * dedup)
{
// Write Content Light Level Information, if present
if (imageMetadata->clli.maxCLL || imageMetadata->clli.maxPALL) {
if (dedup) {
avifItemPropertyDedupStart(dedup);
}
avifBoxMarker clli;
AVIF_CHECKRES(avifRWStreamWriteBox(dedupStream, "clli", AVIF_BOX_SIZE_TBD, &clli));
AVIF_CHECKRES(avifRWStreamWriteU16(dedupStream, imageMetadata->clli.maxCLL)); // unsigned int(16) max_content_light_level;
AVIF_CHECKRES(avifRWStreamWriteU16(dedupStream, imageMetadata->clli.maxPALL)); // unsigned int(16) max_pic_average_light_level;
avifRWStreamFinishBox(dedupStream, clli);
if (dedup) {
AVIF_CHECKRES(avifItemPropertyDedupFinish(dedup, outputStream, ipma, AVIF_FALSE));
}
}
// TODO(maryla): add other HDR boxes: mdcv, cclv, etc.
return AVIF_RESULT_OK;
}
static avifResult avifEncoderWriteExtendedColorProperties(avifRWStream * dedupStream,
avifRWStream * outputStream,
const avifImage * imageMetadata,
struct ipmaArray * ipma,
avifItemPropertyDedup * dedup)
{
// Write (Optional) Transformations
if (imageMetadata->transformFlags & AVIF_TRANSFORM_PASP) {
if (dedup) {
avifItemPropertyDedupStart(dedup);
}
avifBoxMarker pasp;
AVIF_CHECKRES(avifRWStreamWriteBox(dedupStream, "pasp", AVIF_BOX_SIZE_TBD, &pasp));
AVIF_CHECKRES(avifRWStreamWriteU32(dedupStream, imageMetadata->pasp.hSpacing)); // unsigned int(32) hSpacing;
AVIF_CHECKRES(avifRWStreamWriteU32(dedupStream, imageMetadata->pasp.vSpacing)); // unsigned int(32) vSpacing;
avifRWStreamFinishBox(dedupStream, pasp);
if (dedup) {
AVIF_CHECKRES(avifItemPropertyDedupFinish(dedup, outputStream, ipma, AVIF_FALSE));
}
}
if (imageMetadata->transformFlags & AVIF_TRANSFORM_CLAP) {
if (dedup) {
avifItemPropertyDedupStart(dedup);
}
avifBoxMarker clap;
AVIF_CHECKRES(avifRWStreamWriteBox(dedupStream, "clap", AVIF_BOX_SIZE_TBD, &clap));
AVIF_CHECKRES(avifRWStreamWriteU32(dedupStream, imageMetadata->clap.widthN)); // unsigned int(32) cleanApertureWidthN;
AVIF_CHECKRES(avifRWStreamWriteU32(dedupStream, imageMetadata->clap.widthD)); // unsigned int(32) cleanApertureWidthD;
AVIF_CHECKRES(avifRWStreamWriteU32(dedupStream, imageMetadata->clap.heightN)); // unsigned int(32) cleanApertureHeightN;
AVIF_CHECKRES(avifRWStreamWriteU32(dedupStream, imageMetadata->clap.heightD)); // unsigned int(32) cleanApertureHeightD;
AVIF_CHECKRES(avifRWStreamWriteU32(dedupStream, imageMetadata->clap.horizOffN)); // unsigned int(32) horizOffN;
AVIF_CHECKRES(avifRWStreamWriteU32(dedupStream, imageMetadata->clap.horizOffD)); // unsigned int(32) horizOffD;
AVIF_CHECKRES(avifRWStreamWriteU32(dedupStream, imageMetadata->clap.vertOffN)); // unsigned int(32) vertOffN;
AVIF_CHECKRES(avifRWStreamWriteU32(dedupStream, imageMetadata->clap.vertOffD)); // unsigned int(32) vertOffD;
avifRWStreamFinishBox(dedupStream, clap);
if (dedup) {
AVIF_CHECKRES(avifItemPropertyDedupFinish(dedup, outputStream, ipma, AVIF_TRUE));
}
}
if (imageMetadata->transformFlags & AVIF_TRANSFORM_IROT) {
if (dedup) {
avifItemPropertyDedupStart(dedup);
}
avifBoxMarker irot;
AVIF_CHECKRES(avifRWStreamWriteBox(dedupStream, "irot", AVIF_BOX_SIZE_TBD, &irot));
AVIF_CHECKRES(avifRWStreamWriteBits(dedupStream, 0, /*bitCount=*/6)); // unsigned int (6) reserved = 0;
AVIF_CHECKRES(avifRWStreamWriteBits(dedupStream, imageMetadata->irot.angle & 0x3, /*bitCount=*/2)); // unsigned int (2) angle;
avifRWStreamFinishBox(dedupStream, irot);
if (dedup) {
AVIF_CHECKRES(avifItemPropertyDedupFinish(dedup, outputStream, ipma, AVIF_TRUE));
}
}
if (imageMetadata->transformFlags & AVIF_TRANSFORM_IMIR) {
if (dedup) {
avifItemPropertyDedupStart(dedup);
}
avifBoxMarker imir;
AVIF_CHECKRES(avifRWStreamWriteBox(dedupStream, "imir", AVIF_BOX_SIZE_TBD, &imir));
AVIF_CHECKRES(avifRWStreamWriteBits(dedupStream, 0, /*bitCount=*/7)); // unsigned int(7) reserved = 0;
AVIF_CHECKRES(avifRWStreamWriteBits(dedupStream, imageMetadata->imir.axis ? 1 : 0, /*bitCount=*/1)); // unsigned int(1) axis;
avifRWStreamFinishBox(dedupStream, imir);
if (dedup) {
AVIF_CHECKRES(avifItemPropertyDedupFinish(dedup, outputStream, ipma, AVIF_TRUE));
}
}
return AVIF_RESULT_OK;
}
// Write unassociated metadata items (EXIF, XMP) to a small meta box inside of a trak box.
// These items are implicitly associated with the track they are contained within.
static avifResult avifEncoderWriteTrackMetaBox(avifEncoder * encoder, avifRWStream * s)
{
// Count how many non-image items (such as EXIF/XMP) are being written
uint32_t metadataItemCount = 0;
for (uint32_t itemIndex = 0; itemIndex < encoder->data->items.count; ++itemIndex) {
avifEncoderItem * item = &encoder->data->items.item[itemIndex];
if (memcmp(item->type, encoder->data->imageItemType, 4) != 0) {
++metadataItemCount;
}
}
if (metadataItemCount == 0) {
// Don't even bother writing the trak meta box
return AVIF_RESULT_OK;
}
avifBoxMarker meta;
AVIF_CHECKRES(avifRWStreamWriteFullBox(s, "meta", AVIF_BOX_SIZE_TBD, 0, 0, &meta));
avifBoxMarker hdlr;
AVIF_CHECKRES(avifRWStreamWriteFullBox(s, "hdlr", AVIF_BOX_SIZE_TBD, 0, 0, &hdlr));
AVIF_CHECKRES(avifRWStreamWriteU32(s, 0)); // unsigned int(32) pre_defined = 0;
AVIF_CHECKRES(avifRWStreamWriteChars(s, "pict", 4)); // unsigned int(32) handler_type;
AVIF_CHECKRES(avifRWStreamWriteZeros(s, 12)); // const unsigned int(32)[3] reserved = 0;
AVIF_CHECKRES(avifRWStreamWriteChars(s, "libavif", 8)); // string name; (writing null terminator)
avifRWStreamFinishBox(s, hdlr);
avifBoxMarker iloc;
AVIF_CHECKRES(avifRWStreamWriteFullBox(s, "iloc", AVIF_BOX_SIZE_TBD, 0, 0, &iloc));
AVIF_CHECKRES(avifRWStreamWriteBits(s, 4, /*bitCount=*/4)); // unsigned int(4) offset_size;
AVIF_CHECKRES(avifRWStreamWriteBits(s, 4, /*bitCount=*/4)); // unsigned int(4) length_size;
AVIF_CHECKRES(avifRWStreamWriteBits(s, 0, /*bitCount=*/4)); // unsigned int(4) base_offset_size;
AVIF_CHECKRES(avifRWStreamWriteBits(s, 0, /*bitCount=*/4)); // unsigned int(4) reserved;
AVIF_CHECKRES(avifRWStreamWriteU16(s, (uint16_t)metadataItemCount)); // unsigned int(16) item_count;
for (uint32_t trakItemIndex = 0; trakItemIndex < encoder->data->items.count; ++trakItemIndex) {
avifEncoderItem * item = &encoder->data->items.item[trakItemIndex];
if (memcmp(item->type, encoder->data->imageItemType, 4) == 0) {
// Skip over all non-metadata items
continue;
}
AVIF_CHECKRES(avifRWStreamWriteU16(s, item->id)); // unsigned int(16) item_ID;
AVIF_CHECKRES(avifRWStreamWriteU16(s, 0)); // unsigned int(16) data_reference_index;
AVIF_CHECKRES(avifRWStreamWriteU16(s, 1)); // unsigned int(16) extent_count;
AVIF_CHECKRES(avifEncoderItemAddMdatFixup(item, s)); //
AVIF_CHECKRES(avifRWStreamWriteU32(s, 0 /* set later */)); // unsigned int(offset_size*8) extent_offset;
AVIF_CHECKRES(avifRWStreamWriteU32(s, (uint32_t)item->metadataPayload.size)); // unsigned int(length_size*8) extent_length;
}
avifRWStreamFinishBox(s, iloc);
avifBoxMarker iinf;
AVIF_CHECKRES(avifRWStreamWriteFullBox(s, "iinf", AVIF_BOX_SIZE_TBD, 0, 0, &iinf));
AVIF_CHECKRES(avifRWStreamWriteU16(s, (uint16_t)metadataItemCount)); // unsigned int(16) entry_count;
for (uint32_t trakItemIndex = 0; trakItemIndex < encoder->data->items.count; ++trakItemIndex) {
avifEncoderItem * item = &encoder->data->items.item[trakItemIndex];
if (memcmp(item->type, encoder->data->imageItemType, 4) == 0) {
continue;
}
AVIF_ASSERT_OR_RETURN(!item->hiddenImage);
avifBoxMarker infe;
AVIF_CHECKRES(avifRWStreamWriteFullBox(s, "infe", AVIF_BOX_SIZE_TBD, 2, 0, &infe));
AVIF_CHECKRES(avifRWStreamWriteU16(s, item->id)); // unsigned int(16) item_ID;
AVIF_CHECKRES(avifRWStreamWriteU16(s, 0)); // unsigned int(16) item_protection_index;
AVIF_CHECKRES(avifRWStreamWrite(s, item->type, 4)); // unsigned int(32) item_type;
AVIF_CHECKRES(avifRWStreamWriteChars(s, item->infeName, item->infeNameSize)); // string item_name; (writing null terminator)
if (item->infeContentType && item->infeContentTypeSize) { // string content_type; (writing null terminator)
AVIF_CHECKRES(avifRWStreamWriteChars(s, item->infeContentType, item->infeContentTypeSize));
}
avifRWStreamFinishBox(s, infe);
}
avifRWStreamFinishBox(s, iinf);
avifRWStreamFinishBox(s, meta);
return AVIF_RESULT_OK;
}
static avifResult avifWriteGridPayload(avifRWData * data, uint32_t gridCols, uint32_t gridRows, uint32_t gridWidth, uint32_t gridHeight)
{
// ISO/IEC 23008-12 6.6.2.3.2
// aligned(8) class ImageGrid {
// unsigned int(8) version = 0;
// unsigned int(8) flags;
// FieldLength = ((flags & 1) + 1) * 16;
// unsigned int(8) rows_minus_one;
// unsigned int(8) columns_minus_one;
// unsigned int(FieldLength) output_width;
// unsigned int(FieldLength) output_height;
// }
uint8_t gridFlags = ((gridWidth > 65535) || (gridHeight > 65535)) ? 1 : 0;
avifRWStream s;
avifRWStreamStart(&s, data);
AVIF_CHECKRES(avifRWStreamWriteU8(&s, 0)); // unsigned int(8) version = 0;
AVIF_CHECKRES(avifRWStreamWriteU8(&s, gridFlags)); // unsigned int(8) flags;
AVIF_CHECKRES(avifRWStreamWriteU8(&s, (uint8_t)(gridRows - 1))); // unsigned int(8) rows_minus_one;
AVIF_CHECKRES(avifRWStreamWriteU8(&s, (uint8_t)(gridCols - 1))); // unsigned int(8) columns_minus_one;
if (gridFlags & 1) {
AVIF_CHECKRES(avifRWStreamWriteU32(&s, gridWidth)); // unsigned int(FieldLength) output_width;
AVIF_CHECKRES(avifRWStreamWriteU32(&s, gridHeight)); // unsigned int(FieldLength) output_height;
} else {
uint16_t tmpWidth = (uint16_t)gridWidth;
uint16_t tmpHeight = (uint16_t)gridHeight;
AVIF_CHECKRES(avifRWStreamWriteU16(&s, tmpWidth)); // unsigned int(FieldLength) output_width;
AVIF_CHECKRES(avifRWStreamWriteU16(&s, tmpHeight)); // unsigned int(FieldLength) output_height;
}
avifRWStreamFinishWrite(&s);
return AVIF_RESULT_OK;
}
#if defined(AVIF_ENABLE_EXPERIMENTAL_GAIN_MAP)
static avifBool avifWriteToneMappedImagePayload(avifRWData * data, const avifGainMapMetadata * metadata)
{
avifRWStream s;
avifRWStreamStart(&s, data);
const uint8_t version = 0;
AVIF_CHECKRES(avifRWStreamWriteU8(&s, version));
const uint16_t minimumVersion = 0;
AVIF_CHECKRES(avifRWStreamWriteU16(&s, minimumVersion));
const uint16_t writerVersion = 0;
AVIF_CHECKRES(avifRWStreamWriteU16(&s, writerVersion));
uint8_t flags = 0u;
// Always write three channels for now for simplicity.
// TODO(maryla): the draft says that this specifies the count of channels of the
// gain map. But tone mapping is done in RGB space so there are always three
// channels, even if the gain map is grayscale. Should this be revised?
const avifBool allChannelsIdentical =
metadata->gainMapMinN[0] == metadata->gainMapMinN[1] && metadata->gainMapMinN[0] == metadata->gainMapMinN[2] &&
metadata->gainMapMinD[0] == metadata->gainMapMinD[1] && metadata->gainMapMinD[0] == metadata->gainMapMinD[2] &&
metadata->gainMapMaxN[0] == metadata->gainMapMaxN[1] && metadata->gainMapMaxN[0] == metadata->gainMapMaxN[2] &&
metadata->gainMapMaxD[0] == metadata->gainMapMaxD[1] && metadata->gainMapMaxD[0] == metadata->gainMapMaxD[2] &&
metadata->gainMapGammaN[0] == metadata->gainMapGammaN[1] && metadata->gainMapGammaN[0] == metadata->gainMapGammaN[2] &&
metadata->gainMapGammaD[0] == metadata->gainMapGammaD[1] && metadata->gainMapGammaD[0] == metadata->gainMapGammaD[2] &&
metadata->baseOffsetN[0] == metadata->baseOffsetN[1] && metadata->baseOffsetN[0] == metadata->baseOffsetN[2] &&
metadata->baseOffsetD[0] == metadata->baseOffsetD[1] && metadata->baseOffsetD[0] == metadata->baseOffsetD[2] &&
metadata->alternateOffsetN[0] == metadata->alternateOffsetN[1] &&
metadata->alternateOffsetN[0] == metadata->alternateOffsetN[2] &&
metadata->alternateOffsetD[0] == metadata->alternateOffsetD[1] &&
metadata->alternateOffsetD[0] == metadata->alternateOffsetD[2];
const uint8_t channelCount = allChannelsIdentical ? 1u : 3u;
if (channelCount == 3) {
flags |= (1 << 7);
}
if (metadata->useBaseColorSpace) {
flags |= (1 << 6);
}
AVIF_CHECKRES(avifRWStreamWriteU8(&s, flags));
AVIF_CHECKRES(avifRWStreamWriteU32(&s, metadata->baseHdrHeadroomN));
AVIF_CHECKRES(avifRWStreamWriteU32(&s, metadata->baseHdrHeadroomD));
AVIF_CHECKRES(avifRWStreamWriteU32(&s, metadata->alternateHdrHeadroomN));
AVIF_CHECKRES(avifRWStreamWriteU32(&s, metadata->alternateHdrHeadroomD));
for (int c = 0; c < channelCount; ++c) {
AVIF_CHECKRES(avifRWStreamWriteU32(&s, (uint32_t)metadata->gainMapMinN[c]));
AVIF_CHECKRES(avifRWStreamWriteU32(&s, metadata->gainMapMinD[c]));
AVIF_CHECKRES(avifRWStreamWriteU32(&s, (uint32_t)metadata->gainMapMaxN[c]));
AVIF_CHECKRES(avifRWStreamWriteU32(&s, metadata->gainMapMaxD[c]));
AVIF_CHECKRES(avifRWStreamWriteU32(&s, metadata->gainMapGammaN[c]));
AVIF_CHECKRES(avifRWStreamWriteU32(&s, metadata->gainMapGammaD[c]));
AVIF_CHECKRES(avifRWStreamWriteU32(&s, (uint32_t)metadata->baseOffsetN[c]));
AVIF_CHECKRES(avifRWStreamWriteU32(&s, metadata->baseOffsetD[c]));
AVIF_CHECKRES(avifRWStreamWriteU32(&s, (uint32_t)metadata->alternateOffsetN[c]));
AVIF_CHECKRES(avifRWStreamWriteU32(&s, metadata->alternateOffsetD[c]));
}
avifRWStreamFinishWrite(&s);
return AVIF_TRUE;
}
size_t avifEncoderGetGainMapSizeBytes(avifEncoder * encoder)
{
return encoder->data->gainMapSizeBytes;
}
// Sets altImageMetadata's metadata values to represent the "alternate" image as if applying the gain map to the base image.
static avifResult avifImageCopyAltImageMetadata(avifImage * altImageMetadata, const avifImage * imageWithGainMap)
{
altImageMetadata->width = imageWithGainMap->width;
altImageMetadata->height = imageWithGainMap->height;
AVIF_CHECKRES(avifRWDataSet(&altImageMetadata->icc, imageWithGainMap->gainMap->altICC.data, imageWithGainMap->gainMap->altICC.size));
altImageMetadata->colorPrimaries = imageWithGainMap->gainMap->altColorPrimaries;
altImageMetadata->transferCharacteristics = imageWithGainMap->gainMap->altTransferCharacteristics;
altImageMetadata->matrixCoefficients = imageWithGainMap->gainMap->altMatrixCoefficients;
altImageMetadata->yuvRange = imageWithGainMap->gainMap->altYUVRange;
altImageMetadata->depth = imageWithGainMap->gainMap->altDepth
? imageWithGainMap->gainMap->altDepth
: AVIF_MAX(imageWithGainMap->depth, imageWithGainMap->gainMap->image->depth);
altImageMetadata->yuvFormat = (imageWithGainMap->gainMap->altPlaneCount == 1) ? AVIF_PIXEL_FORMAT_YUV400 : AVIF_PIXEL_FORMAT_YUV444;
altImageMetadata->clli = imageWithGainMap->gainMap->altCLLI;
return AVIF_RESULT_OK;
}
#endif // AVIF_ENABLE_EXPERIMENTAL_GAIN_MAP
#if defined(AVIF_ENABLE_EXPERIMENTAL_SAMPLE_TRANSFORM)
static avifResult avifEncoderWriteSampleTransformTokens(avifRWStream * s, const avifSampleTransformExpression * expression)
{
AVIF_ASSERT_OR_RETURN(expression->count <= 256);
AVIF_CHECKRES(avifRWStreamWriteU8(s, (uint8_t)expression->count)); // unsigned int(8) token_count;
for (uint32_t t = 0; t < expression->count; ++t) {
const avifSampleTransformToken * token = &expression->tokens[t];
AVIF_CHECKRES(avifRWStreamWriteU8(s, token->type)); // unsigned int(8) token;
if (token->type == AVIF_SAMPLE_TRANSFORM_CONSTANT) {
// TODO(yguyon): Verify two's complement representation is guaranteed here.
const uint32_t constant = *(const uint32_t *)&token->constant;
AVIF_CHECKRES(avifRWStreamWriteU32(s, constant)); // signed int(1<<(bit_depth+3)) constant;
} else if (token->type == AVIF_SAMPLE_TRANSFORM_INPUT_IMAGE_ITEM_INDEX) {
AVIF_CHECKRES(avifRWStreamWriteU8(s, token->inputImageItemIndex)); // unsigned int(8) input_image_item_index;
}
}
return AVIF_RESULT_OK;
}
static avifResult avifEncoderWriteSampleTransformPayload(avifEncoder * encoder, avifRWData * data)
{
avifRWStream s;
avifRWStreamStart(&s, data);
AVIF_CHECKRES(avifRWStreamWriteBits(&s, 0, /*bitCount=*/6)); // unsigned int(6) version = 0;
// AVIF_SAMPLE_TRANSFORM_BIT_DEPTH_32 is necessary because the two input images
// once combined use 16-bit unsigned values, but intermediate results are stored in signed integers.
AVIF_CHECKRES(avifRWStreamWriteBits(&s, AVIF_SAMPLE_TRANSFORM_BIT_DEPTH_32, /*bitCount=*/2)); // unsigned int(2) bit_depth;
avifSampleTransformExpression expression = { 0 };
AVIF_CHECKRES(avifSampleTransformRecipeToExpression(encoder->sampleTransformRecipe, &expression));
const avifResult result = avifEncoderWriteSampleTransformTokens(&s, &expression);
avifArrayDestroy(&expression);
if (result != AVIF_RESULT_OK) {
avifDiagnosticsPrintf(&encoder->diag, "Failed to write sample transform metadata for recipe %d", (int)encoder->sampleTransformRecipe);
return result;
}
avifRWStreamFinishWrite(&s);
return AVIF_RESULT_OK;
}
#endif // AVIF_ENABLE_EXPERIMENTAL_SAMPLE_TRANSFORM
static avifResult avifEncoderDataCreateExifItem(avifEncoderData * data, const avifRWData * exif)
{
size_t exifTiffHeaderOffset;
const avifResult result = avifGetExifTiffHeaderOffset(exif->data, exif->size, &exifTiffHeaderOffset);
if (result != AVIF_RESULT_OK) {
// Couldn't find the TIFF header
return result;
}
avifEncoderItem * exifItem = avifEncoderDataCreateItem(data, "Exif", "Exif", 5, 0);
if (!exifItem) {
return AVIF_RESULT_OUT_OF_MEMORY;
}
exifItem->irefToID = data->primaryItemID;
exifItem->irefType = "cdsc";
const uint32_t offset32bit = avifHTONL((uint32_t)exifTiffHeaderOffset);
AVIF_CHECKRES(avifRWDataRealloc(&exifItem->metadataPayload, sizeof(offset32bit) + exif->size));
memcpy(exifItem->metadataPayload.data, &offset32bit, sizeof(offset32bit));
memcpy(exifItem->metadataPayload.data + sizeof(offset32bit), exif->data, exif->size);
return AVIF_RESULT_OK;
}
static avifResult avifEncoderDataCreateXMPItem(avifEncoderData * data, const avifRWData * xmp)
{
avifEncoderItem * xmpItem = avifEncoderDataCreateItem(data, "mime", "XMP", 4, 0);
if (!xmpItem) {
return AVIF_RESULT_OUT_OF_MEMORY;
}
xmpItem->irefToID = data->primaryItemID;
xmpItem->irefType = "cdsc";
xmpItem->infeContentType = xmpContentType;
xmpItem->infeContentTypeSize = xmpContentTypeSize;
AVIF_CHECKRES(avifRWDataSet(&xmpItem->metadataPayload, xmp->data, xmp->size));
return AVIF_RESULT_OK;
}
// Same as avifImageCopy() but pads the dstImage with border pixel values to reach dstWidth and dstHeight.
static avifResult avifImageCopyAndPad(avifImage * const dstImage, const avifImage * srcImage, uint32_t dstWidth, uint32_t dstHeight)
{
AVIF_ASSERT_OR_RETURN(dstImage);
AVIF_ASSERT_OR_RETURN(!dstImage->width && !dstImage->height); // dstImage is not set yet.
AVIF_ASSERT_OR_RETURN(dstWidth >= srcImage->width);
AVIF_ASSERT_OR_RETURN(dstHeight >= srcImage->height);
// Copy all fields but do not allocate the planes.
AVIF_CHECKRES(avifImageCopy(dstImage, srcImage, (avifPlanesFlag)0));
dstImage->width = dstWidth;
dstImage->height = dstHeight;
if (srcImage->yuvPlanes[AVIF_CHAN_Y]) {
AVIF_CHECKRES(avifImageAllocatePlanes(dstImage, AVIF_PLANES_YUV));
}
if (srcImage->alphaPlane) {
AVIF_CHECKRES(avifImageAllocatePlanes(dstImage, AVIF_PLANES_A));
}
const avifBool usesU16 = avifImageUsesU16(srcImage);
for (int plane = AVIF_CHAN_Y; plane <= AVIF_CHAN_A; ++plane) {
const uint8_t * srcRow = avifImagePlane(srcImage, plane);
const uint32_t srcRowBytes = avifImagePlaneRowBytes(srcImage, plane);
const uint32_t srcPlaneWidth = avifImagePlaneWidth(srcImage, plane);
const uint32_t srcPlaneHeight = avifImagePlaneHeight(srcImage, plane); // 0 for A if no alpha and 0 for UV if 4:0:0.
const size_t srcPlaneWidthBytes = (size_t)srcPlaneWidth << usesU16;
uint8_t * dstRow = avifImagePlane(dstImage, plane);
const uint32_t dstRowBytes = avifImagePlaneRowBytes(dstImage, plane);
const uint32_t dstPlaneWidth = avifImagePlaneWidth(dstImage, plane);
const uint32_t dstPlaneHeight = avifImagePlaneHeight(dstImage, plane); // 0 for A if no alpha and 0 for UV if 4:0:0.
const size_t dstPlaneWidthBytes = (size_t)dstPlaneWidth << usesU16;
for (uint32_t j = 0; j < srcPlaneHeight; ++j) {
memcpy(dstRow, srcRow, srcPlaneWidthBytes);
// Pad columns.
if (dstPlaneWidth > srcPlaneWidth) {
if (usesU16) {
uint16_t * dstRow16 = (uint16_t *)dstRow;
for (uint32_t x = srcPlaneWidth; x < dstPlaneWidth; ++x) {
dstRow16[x] = dstRow16[srcPlaneWidth - 1];
}
} else {
memset(&dstRow[srcPlaneWidth], dstRow[srcPlaneWidth - 1], dstPlaneWidth - srcPlaneWidth);
}
}
srcRow += srcRowBytes;
dstRow += dstRowBytes;
}
// Pad rows.
for (uint32_t j = srcPlaneHeight; j < dstPlaneHeight; ++j) {
memcpy(dstRow, dstRow - dstRowBytes, dstPlaneWidthBytes);
dstRow += dstRowBytes;
}
}
return AVIF_RESULT_OK;
}
static int avifQualityToQuantizer(int quality, int minQuantizer, int maxQuantizer)
{
int quantizer;
if (quality == AVIF_QUALITY_DEFAULT) {
// In older libavif releases, avifEncoder didn't have the quality and qualityAlpha fields.
// Supply a default value for quantizer.
quantizer = (minQuantizer + maxQuantizer) / 2;
quantizer = AVIF_CLAMP(quantizer, 0, 63);
} else {
quality = AVIF_CLAMP(quality, 0, 100);
quantizer = ((100 - quality) * 63 + 50) / 100;
}
return quantizer;
}
static const char infeNameColor[] = "Color";
static const char infeNameAlpha[] = "Alpha";
#if defined(AVIF_ENABLE_EXPERIMENTAL_GAIN_MAP)
static const char infeNameGainMap[] = "GMap";
#endif
#if defined(AVIF_ENABLE_EXPERIMENTAL_SAMPLE_TRANSFORM)
static const char infeNameSampleTransform[] = "SampleTransform";
#endif
static const char * getInfeName(avifItemCategory itemCategory)
{
if (avifIsAlpha(itemCategory)) {
return infeNameAlpha;
}
#if defined(AVIF_ENABLE_EXPERIMENTAL_GAIN_MAP)
if (itemCategory == AVIF_ITEM_GAIN_MAP) {
return infeNameGainMap;
}
#endif
#if defined(AVIF_ENABLE_EXPERIMENTAL_SAMPLE_TRANSFORM)
if (itemCategory >= AVIF_SAMPLE_TRANSFORM_MIN_CATEGORY && itemCategory <= AVIF_SAMPLE_TRANSFORM_MAX_CATEGORY) {
return infeNameSampleTransform;
}
#endif
return infeNameColor;
}
// Adds the items for a single cell or a grid of cells. Outputs the topLevelItemID which is
// the only item if there is exactly one cell, or the grid item for multiple cells.
// Note: The topLevelItemID output argument has the type uint16_t* instead of avifEncoderItem** because
// the avifEncoderItem pointer may be invalidated by a call to avifEncoderDataCreateItem().
static avifResult avifEncoderAddImageItems(avifEncoder * encoder,
uint32_t gridCols,
uint32_t gridRows,
uint32_t gridWidth,
uint32_t gridHeight,
avifItemCategory itemCategory,
uint16_t * topLevelItemID)
{
const uint32_t cellCount = gridCols * gridRows;
const char * infeName = getInfeName(itemCategory);
const size_t infeNameSize = strlen(infeName) + 1;
if (cellCount > 1) {
avifEncoderItem * gridItem = avifEncoderDataCreateItem(encoder->data, "grid", infeName, infeNameSize, 0);
AVIF_CHECKRES(avifWriteGridPayload(&gridItem->metadataPayload, gridCols, gridRows, gridWidth, gridHeight));
gridItem->itemCategory = itemCategory;
gridItem->gridCols = gridCols;
gridItem->gridRows = gridRows;
gridItem->gridWidth = gridWidth;
gridItem->gridHeight = gridHeight;
*topLevelItemID = gridItem->id;
}
for (uint32_t cellIndex = 0; cellIndex < cellCount; ++cellIndex) {
avifEncoderItem * item =
avifEncoderDataCreateItem(encoder->data, encoder->data->imageItemType, infeName, infeNameSize, cellIndex);
AVIF_CHECKERR(item, AVIF_RESULT_OUT_OF_MEMORY);
AVIF_CHECKRES(avifCodecCreate(encoder->codecChoice, AVIF_CODEC_FLAG_CAN_ENCODE, &item->codec));
item->codec->csOptions = encoder->csOptions;
item->codec->diag = &encoder->diag;
item->itemCategory = itemCategory;
item->extraLayerCount = encoder->extraLayerCount;
if (cellCount > 1) {
item->dimgFromID = *topLevelItemID;
item->hiddenImage = AVIF_TRUE;
} else {
*topLevelItemID = item->id;
}
}
return AVIF_RESULT_OK;
}
#if defined(AVIF_ENABLE_EXPERIMENTAL_SAMPLE_TRANSFORM)
static avifResult avifEncoderCreateBitDepthExtensionItems(avifEncoder * encoder,
uint32_t gridCols,
uint32_t gridRows,
uint32_t gridWidth,
uint32_t gridHeight,
uint16_t colorItemID)
{
AVIF_ASSERT_OR_RETURN(encoder->sampleTransformRecipe == AVIF_SAMPLE_TRANSFORM_BIT_DEPTH_EXTENSION_8B_8B ||
encoder->sampleTransformRecipe == AVIF_SAMPLE_TRANSFORM_BIT_DEPTH_EXTENSION_12B_4B);
// There are multiple possible ISOBMFF box hierarchies for translucent images,
// using 'sato' (Sample Transform) derived image items:
// - a primary 'sato' item uses a main color coded item and a hidden color coded item; each color coded
// item has an auxiliary alpha coded item; the main color coded item and the 'sato' item are in
// an 'altr' group (backward-compatible, implemented)
// - a primary 'sato' item uses a main color coded item and a hidden color coded item; the primary
// 'sato' item has an auxiliary alpha 'sato' item using two alpha coded items (backward-incompatible)
// Likewise, there are multiple possible ISOBMFF box hierarchies for bit-depth-extended grids,
// using 'sato' (Sample Transform) derived image items:
// - a primary color 'grid', an auxiliary alpha 'grid', a hidden color 'grid', a hidden auxiliary alpha 'grid'
// and a 'sato' using the two color 'grid's as input items in this order; the primary color item
// and the 'sato' item being in an 'altr' group (backward-compatible, implemented)
// - a primary 'grid' of 'sato' cells and an auxiliary alpha 'grid' of 'sato' cells (backward-incompatible)
avifEncoderItem * sampleTransformItem = avifEncoderDataCreateItem(encoder->data,
"sato",
infeNameSampleTransform,
/*infeNameSize=*/strlen(infeNameSampleTransform) + 1,
/*cellIndex=*/0);
AVIF_CHECKRES(avifEncoderWriteSampleTransformPayload(encoder, &sampleTransformItem->metadataPayload));
sampleTransformItem->itemCategory = AVIF_ITEM_SAMPLE_TRANSFORM;
uint16_t sampleTransformItemID = sampleTransformItem->id;
// 'altr' group
uint16_t * alternativeItemID = (uint16_t *)avifArrayPush(&encoder->data->alternativeItemIDs);
AVIF_CHECKERR(alternativeItemID != NULL, AVIF_RESULT_OUT_OF_MEMORY);
*alternativeItemID = sampleTransformItem->id;
alternativeItemID = (uint16_t *)avifArrayPush(&encoder->data->alternativeItemIDs);
AVIF_CHECKERR(alternativeItemID != NULL, AVIF_RESULT_OUT_OF_MEMORY);
*alternativeItemID = colorItemID;
uint16_t bitDepthExtensionColorItemId;
AVIF_CHECKRES(
avifEncoderAddImageItems(encoder, gridCols, gridRows, gridWidth, gridHeight, AVIF_ITEM_SAMPLE_TRANSFORM_INPUT_0_COLOR, &bitDepthExtensionColorItemId));
avifEncoderItem * bitDepthExtensionColorItem = avifEncoderDataFindItemByID(encoder->data, bitDepthExtensionColorItemId);
assert(bitDepthExtensionColorItem);
bitDepthExtensionColorItem->hiddenImage = AVIF_TRUE;
// Set the color and bit depth extension items' dimgFromID value to point to the sample transform item.
// The color item shall be first, and the bit depth extension item second. avifEncoderFinish() writes the
// dimg item references in item id order, so as long as colorItemID < bitDepthExtensionColorItemId, the order
// will be correct.
AVIF_ASSERT_OR_RETURN(colorItemID < bitDepthExtensionColorItemId);
avifEncoderItem * colorItem = avifEncoderDataFindItemByID(encoder->data, colorItemID);
AVIF_ASSERT_OR_RETURN(colorItem != NULL);
AVIF_ASSERT_OR_RETURN(colorItem->dimgFromID == 0); // Our internal API only allows one dimg value per item.
colorItem->dimgFromID = sampleTransformItemID;
bitDepthExtensionColorItem->dimgFromID = sampleTransformItemID;
if (encoder->data->alphaPresent) {
uint16_t bitDepthExtensionAlphaItemId;
AVIF_CHECKRES(
avifEncoderAddImageItems(encoder, gridCols, gridRows, gridWidth, gridHeight, AVIF_ITEM_SAMPLE_TRANSFORM_INPUT_0_ALPHA, &bitDepthExtensionAlphaItemId));
avifEncoderItem * bitDepthExtensionAlphaItem = avifEncoderDataFindItemByID(encoder->data, bitDepthExtensionAlphaItemId);
assert(bitDepthExtensionAlphaItem);
bitDepthExtensionAlphaItem->irefType = "auxl";
bitDepthExtensionAlphaItem->irefToID = bitDepthExtensionColorItemId;
if (encoder->data->imageMetadata->alphaPremultiplied) {
// The reference may have changed; fetch it again.
bitDepthExtensionColorItem = avifEncoderDataFindItemByID(encoder->data, bitDepthExtensionColorItemId);
assert(bitDepthExtensionColorItem);
bitDepthExtensionColorItem->irefType = "prem";
bitDepthExtensionColorItem->irefToID = bitDepthExtensionAlphaItemId;
}
}
return AVIF_RESULT_OK;
}
// Same as avifImageApplyExpression() but for the expression (inputImageItem [op] constant).
// Convenience function.
static avifResult avifImageApplyImgOpConst(avifImage * result,
const avifImage * inputImageItem,
avifSampleTransformTokenType op,
int32_t constant,
avifPlanesFlags planes)
{
// Postfix notation.
const avifSampleTransformToken tokens[] = { { AVIF_SAMPLE_TRANSFORM_INPUT_IMAGE_ITEM_INDEX, 0, /*inputImageItemIndex=*/1 },
{ AVIF_SAMPLE_TRANSFORM_CONSTANT, constant, 0 },
{ (uint8_t)op, 0, 0 } };
return avifImageApplyOperations(result, AVIF_SAMPLE_TRANSFORM_BIT_DEPTH_32, /*numTokens=*/3, tokens, /*numInputImageItems=*/1, &inputImageItem, planes);
}
static avifResult avifImageCreateAllocate(avifImage ** sampleTransformedImage, const avifImage * reference, uint32_t numBits, avifPlanesFlag planes)
{
*sampleTransformedImage = avifImageCreate(reference->width, reference->height, numBits, reference->yuvFormat);
AVIF_CHECKERR(*sampleTransformedImage != NULL, AVIF_RESULT_OUT_OF_MEMORY);
return avifImageAllocatePlanes(*sampleTransformedImage, planes);
}
static avifResult avifEncoderCreateSatoImage(const avifEncoder * encoder,
const avifEncoderItem * item,
avifBool itemWillBeEncodedLosslessly,
const avifImage * image,
avifImage ** sampleTransformedImage)
{
const avifPlanesFlag planes = avifIsAlpha(item->itemCategory) ? AVIF_PLANES_A : AVIF_PLANES_YUV;
// The first image item used as input to the 'sato' Sample Transform derived image item.
avifBool isBase = item->itemCategory == AVIF_ITEM_COLOR || item->itemCategory == AVIF_ITEM_ALPHA;
if (!isBase) {
// The second image item used as input to the 'sato' Sample Transform derived image item.
AVIF_ASSERT_OR_RETURN(item->itemCategory >= AVIF_SAMPLE_TRANSFORM_MIN_CATEGORY &&
item->itemCategory <= AVIF_SAMPLE_TRANSFORM_MAX_CATEGORY);
}
if (encoder->sampleTransformRecipe == AVIF_SAMPLE_TRANSFORM_BIT_DEPTH_EXTENSION_8B_8B) {
if (isBase) {
AVIF_CHECKRES(avifImageCreateAllocate(sampleTransformedImage, image, 8, planes));
AVIF_CHECKRES(avifImageApplyImgOpConst(*sampleTransformedImage, image, AVIF_SAMPLE_TRANSFORM_DIVIDE, 256, planes));
} else {
AVIF_CHECKRES(avifImageCreateAllocate(sampleTransformedImage, image, 8, planes));
AVIF_CHECKRES(avifImageApplyImgOpConst(*sampleTransformedImage, image, AVIF_SAMPLE_TRANSFORM_AND, 255, planes));
}
} else {
AVIF_CHECKERR(encoder->sampleTransformRecipe == AVIF_SAMPLE_TRANSFORM_BIT_DEPTH_EXTENSION_12B_4B, AVIF_RESULT_NOT_IMPLEMENTED);
if (isBase) {
AVIF_CHECKRES(avifImageCreateAllocate(sampleTransformedImage, image, 12, planes));
AVIF_CHECKRES(avifImageApplyImgOpConst(*sampleTransformedImage, image, AVIF_SAMPLE_TRANSFORM_DIVIDE, 16, planes));
} else {
AVIF_CHECKRES(avifImageCreateAllocate(sampleTransformedImage, image, 8, planes));
AVIF_CHECKRES(avifImageApplyImgOpConst(*sampleTransformedImage, image, AVIF_SAMPLE_TRANSFORM_AND, 15, planes));
// AVIF only supports 8, 10 or 12-bit image items. Scale the samples to fit the range.
// Note: The samples could be encoded as is without being shifted left before encoding,
// but they would not be shifted right after decoding either. Right shifting after
// decoding provides a guarantee on the range of values and on the lack of integer
// overflow, so it is safer to do these extra steps.
// It also makes more sense from a compression point-of-view to use the full range.
// Transform in-place.
AVIF_CHECKRES(
avifImageApplyImgOpConst(*sampleTransformedImage, *sampleTransformedImage, AVIF_SAMPLE_TRANSFORM_PRODUCT, 16, planes));
if (!itemWillBeEncodedLosslessly) {
// Small loss at encoding could be amplified by the truncation caused by the right
// shift after decoding. Offset sample values now, before encoding, to round rather
// than floor the samples shifted after decoding.
// Note: Samples were just left shifted by numShiftedBits, so adding less than
// (1<<numShiftedBits) will not trigger any integer overflow.
// Transform in-place.
AVIF_CHECKRES(
avifImageApplyImgOpConst(*sampleTransformedImage, *sampleTransformedImage, AVIF_SAMPLE_TRANSFORM_SUM, 7, planes));
}
}
}
return AVIF_RESULT_OK;
}
static avifResult avifEncoderCreateBitDepthExtensionImage(const avifEncoder * encoder,
const avifEncoderItem * item,
avifBool itemWillBeEncodedLosslessly,
const avifImage * image,
avifImage ** sampleTransformedImage)
{
AVIF_ASSERT_OR_RETURN(image->depth == 16); // Other bit depths could be supported but for now it is 16-bit only.
*sampleTransformedImage = NULL;
const avifResult result = avifEncoderCreateSatoImage(encoder, item, itemWillBeEncodedLosslessly, image, sampleTransformedImage);
if (result != AVIF_RESULT_OK && *sampleTransformedImage != NULL) {
avifImageDestroy(*sampleTransformedImage);
}
return result;
}
#endif // AVIF_ENABLE_EXPERIMENTAL_SAMPLE_TRANSFORM
static avifCodecType avifEncoderGetCodecType(const avifEncoder * encoder)
{
// TODO(yguyon): Rework when AVIF_CODEC_CHOICE_AUTO can be AVM
assert((encoder->codecChoice != AVIF_CODEC_CHOICE_AUTO) ||
(strcmp(avifCodecName(encoder->codecChoice, AVIF_CODEC_FLAG_CAN_ENCODE), "avm") != 0));
return avifCodecTypeFromChoice(encoder->codecChoice, AVIF_CODEC_FLAG_CAN_ENCODE);
}
// This function is called after every color frame is encoded. It returns AVIF_TRUE if a keyframe needs to be forced for the next
// alpha frame to be encoded, AVIF_FALSE otherwise.
static avifBool avifEncoderDataShouldForceKeyframeForAlpha(const avifEncoderData * data,
const avifEncoderItem * colorItem,
avifAddImageFlags addImageFlags)
{
if (!data->alphaPresent) {
// There is no alpha plane.
return AVIF_FALSE;
}
if (addImageFlags & AVIF_ADD_IMAGE_FLAG_SINGLE) {
// Not an animated image.
return AVIF_FALSE;
}
if (data->frames.count == 0) {
// data->frames.count is the number of frames that have been encoded so far by previous calls to avifEncoderAddImage. If
// this is the first frame, there is no need to force keyframe.
return AVIF_FALSE;
}
const uint32_t colorFramesOutputSoFar = colorItem->encodeOutput->samples.count;
const avifBool isLaggedOutput = (data->frames.count + 1) != colorFramesOutputSoFar;
if (isLaggedOutput) {
// If the encoder is operating with lag, then there is no way to determine if the last encoded frame was a keyframe until
// the encoder outputs it (after the lag). So do not force keyframe for alpha channel in this case.
return AVIF_FALSE;
}
return colorItem->encodeOutput->samples.sample[colorFramesOutputSoFar - 1].sync;
}
static avifResult avifGetErrorForItemCategory(avifItemCategory itemCategory)
{
#if defined(AVIF_ENABLE_EXPERIMENTAL_GAIN_MAP)
if (itemCategory == AVIF_ITEM_GAIN_MAP) {
return AVIF_RESULT_ENCODE_GAIN_MAP_FAILED;
}
#endif
#if defined(AVIF_ENABLE_EXPERIMENTAL_SAMPLE_TRANSFORM)
if (itemCategory == AVIF_ITEM_SAMPLE_TRANSFORM ||
(itemCategory >= AVIF_SAMPLE_TRANSFORM_MIN_CATEGORY && itemCategory <= AVIF_SAMPLE_TRANSFORM_MAX_CATEGORY)) {
return AVIF_RESULT_ENCODE_SAMPLE_TRANSFORM_FAILED;
}
#endif
return avifIsAlpha(itemCategory) ? AVIF_RESULT_ENCODE_ALPHA_FAILED : AVIF_RESULT_ENCODE_COLOR_FAILED;
}
static uint32_t avifGridWidth(uint32_t gridCols, const avifImage * firstCell, const avifImage * bottomRightCell)
{
return (gridCols - 1) * firstCell->width + bottomRightCell->width;
}
static uint32_t avifGridHeight(uint32_t gridRows, const avifImage * firstCell, const avifImage * bottomRightCell)
{
return (gridRows - 1) * firstCell->height + bottomRightCell->height;
}
static avifResult avifValidateGrid(uint32_t gridCols,
uint32_t gridRows,
const avifImage * const * cellImages,
avifBool validateGainMap,
avifDiagnostics * diag)
{
const uint32_t cellCount = gridCols * gridRows;
const avifImage * firstCell = cellImages[0];
const avifImage * bottomRightCell = cellImages[cellCount - 1];
#if defined(AVIF_ENABLE_EXPERIMENTAL_GAIN_MAP)
if (validateGainMap) {
AVIF_ASSERT_OR_RETURN(firstCell->gainMap && firstCell->gainMap->image);
firstCell = firstCell->gainMap->image;
AVIF_ASSERT_OR_RETURN(bottomRightCell->gainMap && bottomRightCell->gainMap->image);
bottomRightCell = bottomRightCell->gainMap->image;
}
#endif
const uint32_t tileWidth = firstCell->width;
const uint32_t tileHeight = firstCell->height;
const uint32_t gridWidth = avifGridWidth(gridCols, firstCell, bottomRightCell);
const uint32_t gridHeight = avifGridHeight(gridRows, firstCell, bottomRightCell);
for (uint32_t cellIndex = 0; cellIndex < cellCount; ++cellIndex) {
const avifImage * cellImage = cellImages[cellIndex];
#if defined(AVIF_ENABLE_EXPERIMENTAL_GAIN_MAP)
if (validateGainMap) {
AVIF_ASSERT_OR_RETURN(cellImage->gainMap && cellImage->gainMap->image);
cellImage = cellImage->gainMap->image;
}
#endif
const uint32_t expectedCellWidth = ((cellIndex + 1) % gridCols) ? tileWidth : bottomRightCell->width;
const uint32_t expectedCellHeight = (cellIndex < (cellCount - gridCols)) ? tileHeight : bottomRightCell->height;
if ((cellImage->width != expectedCellWidth) || (cellImage->height != expectedCellHeight)) {
avifDiagnosticsPrintf(diag,
"%s cell %u has invalid dimensions: expected %ux%u found %ux%u",
validateGainMap ? "gain map" : "image",
cellIndex,
expectedCellWidth,
expectedCellHeight,
cellImage->width,
cellImage->height);
return AVIF_RESULT_INVALID_IMAGE_GRID;
}
// 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, chroma sampling format, and the
// same decoder configuration (see 7.3.6.2).
if ((cellImage->depth != firstCell->depth) || (cellImage->yuvFormat != firstCell->yuvFormat) ||
(cellImage->yuvRange != firstCell->yuvRange) || (cellImage->colorPrimaries != firstCell->colorPrimaries) ||
(cellImage->transferCharacteristics != firstCell->transferCharacteristics) ||
(cellImage->matrixCoefficients != firstCell->matrixCoefficients) || (!!cellImage->alphaPlane != !!firstCell->alphaPlane) ||
(cellImage->alphaPremultiplied != firstCell->alphaPremultiplied)) {
avifDiagnosticsPrintf(diag,
"all grid cells should have the same value for: depth, yuvFormat, yuvRange, colorPrimaries, "
"transferCharacteristics, matrixCoefficients, alphaPlane presence, alphaPremultiplied");
return AVIF_RESULT_INVALID_IMAGE_GRID;
}
if (!cellImage->yuvPlanes[AVIF_CHAN_Y]) {
return AVIF_RESULT_NO_CONTENT;
}
}
if ((bottomRightCell->width > tileWidth) || (bottomRightCell->height > tileHeight)) {
avifDiagnosticsPrintf(diag,
"the last %s cell can be smaller but not larger than the other cells which are %ux%u, found %ux%u",
validateGainMap ? "gain map" : "image",
tileWidth,
tileHeight,
bottomRightCell->width,
bottomRightCell->height);
return AVIF_RESULT_INVALID_IMAGE_GRID;
}
if ((cellCount > 1) && !avifAreGridDimensionsValid(firstCell->yuvFormat, gridWidth, gridHeight, tileWidth, tileHeight, diag)) {
return AVIF_RESULT_INVALID_IMAGE_GRID;
}
return AVIF_RESULT_OK;
}
static avifResult avifEncoderAddImageInternal(avifEncoder * encoder,
uint32_t gridCols,
uint32_t gridRows,
const avifImage * const * cellImages,
uint64_t durationInTimescales,
avifAddImageFlags addImageFlags)
{
// -----------------------------------------------------------------------
// Verify encoding is possible
if (!avifCodecName(encoder->codecChoice, AVIF_CODEC_FLAG_CAN_ENCODE)) {
return AVIF_RESULT_NO_CODEC_AVAILABLE;
}
if (encoder->extraLayerCount >= AVIF_MAX_AV1_LAYER_COUNT) {
avifDiagnosticsPrintf(&encoder->diag, "extraLayerCount [%u] must be less than %d", encoder->extraLayerCount, AVIF_MAX_AV1_LAYER_COUNT);
return AVIF_RESULT_INVALID_ARGUMENT;
}
// -----------------------------------------------------------------------
// Validate images
const uint32_t cellCount = gridCols * gridRows;
if (cellCount == 0) {
return AVIF_RESULT_INVALID_ARGUMENT;
}
const avifImage * firstCell = cellImages[0];
const avifImage * bottomRightCell = cellImages[cellCount - 1];
#if defined(AVIF_ENABLE_EXPERIMENTAL_SAMPLE_TRANSFORM)
AVIF_CHECKERR(firstCell->depth == 8 || firstCell->depth == 10 || firstCell->depth == 12 ||
(firstCell->depth == 16 && encoder->sampleTransformRecipe != AVIF_SAMPLE_TRANSFORM_NONE),
AVIF_RESULT_UNSUPPORTED_DEPTH);
#else
AVIF_CHECKERR(firstCell->depth == 8 || firstCell->depth == 10 || firstCell->depth == 12, AVIF_RESULT_UNSUPPORTED_DEPTH);
#endif
AVIF_CHECKERR(firstCell->yuvFormat != AVIF_PIXEL_FORMAT_NONE, AVIF_RESULT_NO_YUV_FORMAT_SELECTED);
if (!firstCell->width || !firstCell->height || !bottomRightCell->width || !bottomRightCell->height) {
return AVIF_RESULT_NO_CONTENT;
}
AVIF_CHECKRES(avifValidateGrid(gridCols, gridRows, cellImages, /*validateGainMap=*/AVIF_FALSE, &encoder->diag));
#if defined(AVIF_ENABLE_EXPERIMENTAL_GAIN_MAP)
const avifBool hasGainMap = (firstCell->gainMap && firstCell->gainMap->image != NULL);
// Check that either all cells have a gain map, or none of them do.
// If a gain map is present, check that they all have the same gain map metadata.
for (uint32_t cellIndex = 0; cellIndex < cellCount; ++cellIndex) {
const avifImage * cellImage = cellImages[cellIndex];
const avifBool cellHasGainMap = (cellImage->gainMap && cellImage->gainMap->image);
if (cellHasGainMap != hasGainMap) {
avifDiagnosticsPrintf(&encoder->diag, "cells should either all have a gain map image, or none of them should, found a mix");
return AVIF_RESULT_INVALID_IMAGE_GRID;
}
if (hasGainMap) {
const avifGainMap * firstGainMap = firstCell->gainMap;
const avifGainMap * cellGainMap = cellImage->gainMap;
if (cellGainMap->altICC.size != firstGainMap->altICC.size ||
memcmp(cellGainMap->altICC.data, firstGainMap->altICC.data, cellGainMap->altICC.size) != 0 ||
cellGainMap->altColorPrimaries != firstGainMap->altColorPrimaries ||
cellGainMap->altTransferCharacteristics != firstGainMap->altTransferCharacteristics ||
cellGainMap->altMatrixCoefficients != firstGainMap->altMatrixCoefficients ||
cellGainMap->altYUVRange != firstGainMap->altYUVRange || cellGainMap->altDepth != firstGainMap->altDepth ||
cellGainMap->altPlaneCount != firstGainMap->altPlaneCount || cellGainMap->altCLLI.maxCLL != firstGainMap->altCLLI.maxCLL ||
cellGainMap->altCLLI.maxPALL != firstGainMap->altCLLI.maxPALL) {
avifDiagnosticsPrintf(&encoder->diag, "all cells should have the same alternate image metadata in the gain map");
return AVIF_RESULT_INVALID_IMAGE_GRID;
}
const avifGainMapMetadata * firstMetadata = &firstGainMap->metadata;
const avifGainMapMetadata * cellMetadata = &cellGainMap->metadata;
if (cellMetadata->baseHdrHeadroomN != firstMetadata->baseHdrHeadroomN ||
cellMetadata->baseHdrHeadroomD != firstMetadata->baseHdrHeadroomD ||
cellMetadata->alternateHdrHeadroomN != firstMetadata->alternateHdrHeadroomN ||
cellMetadata->alternateHdrHeadroomD != firstMetadata->alternateHdrHeadroomD) {
avifDiagnosticsPrintf(&encoder->diag, "all cells should have the same gain map metadata");
return AVIF_RESULT_INVALID_IMAGE_GRID;
}
for (int c = 0; c < 3; ++c) {
if (cellMetadata->gainMapMinN[c] != firstMetadata->gainMapMinN[c] ||
cellMetadata->gainMapMinD[c] != firstMetadata->gainMapMinD[c] ||
cellMetadata->gainMapMaxN[c] != firstMetadata->gainMapMaxN[c] ||
cellMetadata->gainMapMaxD[c] != firstMetadata->gainMapMaxD[c] ||
cellMetadata->gainMapGammaN[c] != firstMetadata->gainMapGammaN[c] ||
cellMetadata->gainMapGammaD[c] != firstMetadata->gainMapGammaD[c] ||
cellMetadata->baseOffsetN[c] != firstMetadata->baseOffsetN[c] ||
cellMetadata->baseOffsetD[c] != firstMetadata->baseOffsetD[c] ||
cellMetadata->alternateOffsetN[c] != firstMetadata->alternateOffsetN[c] ||
cellMetadata->alternateOffsetD[c] != firstMetadata->alternateOffsetD[c]) {
avifDiagnosticsPrintf(&encoder->diag, "all cells should have the same gain map metadata");
return AVIF_RESULT_INVALID_IMAGE_GRID;
}
}
}
}
if (hasGainMap) {
// AVIF supports 16-bit images through sample transforms used as bit depth extensions,
// but this is not implemented for gain maps for now. Stick to at most 12 bits.
// TODO(yguyon): Implement 16-bit gain maps.
AVIF_CHECKERR(firstCell->gainMap->image->depth == 8 || firstCell->gainMap->image->depth == 10 ||
firstCell->gainMap->image->depth == 12,
AVIF_RESULT_UNSUPPORTED_DEPTH);
AVIF_CHECKERR(firstCell->gainMap->image->yuvFormat != AVIF_PIXEL_FORMAT_NONE, AVIF_RESULT_NO_YUV_FORMAT_SELECTED);
AVIF_CHECKRES(avifValidateGrid(gridCols, gridRows, cellImages, /*validateGainMap=*/AVIF_TRUE, &encoder->diag));
if (firstCell->gainMap->image->colorPrimaries != AVIF_COLOR_PRIMARIES_UNSPECIFIED ||
firstCell->gainMap->image->transferCharacteristics != AVIF_TRANSFER_CHARACTERISTICS_UNSPECIFIED) {
avifDiagnosticsPrintf(&encoder->diag, "the gain map image must have colorPrimaries = 2 and transferCharacteristics = 2");
return AVIF_RESULT_INVALID_ARGUMENT;
}
}
#endif // AVIF_ENABLE_EXPERIMENTAL_GAIN_MAP
// -----------------------------------------------------------------------
// Validate flags
if (encoder->data->singleImage) {
// The previous call to avifEncoderAddImage() set AVIF_ADD_IMAGE_FLAG_SINGLE.
// avifEncoderAddImage() cannot be called again for this encode.
return AVIF_RESULT_ENCODE_COLOR_FAILED;
}
if (addImageFlags & AVIF_ADD_IMAGE_FLAG_SINGLE) {
encoder->data->singleImage = AVIF_TRUE;
if (encoder->extraLayerCount > 0) {
// AVIF_ADD_IMAGE_FLAG_SINGLE may not be set for layered image.
return AVIF_RESULT_INVALID_ARGUMENT;
}
if (encoder->data->items.count > 0) {
// AVIF_ADD_IMAGE_FLAG_SINGLE may only be set on the first and only image.
return AVIF_RESULT_INVALID_ARGUMENT;
}
}
// -----------------------------------------------------------------------
// Choose AV1 or AV2
const avifCodecType codecType = avifEncoderGetCodecType(encoder);
switch (codecType) {
case AVIF_CODEC_TYPE_AV1:
encoder->data->imageItemType = "av01";
encoder->data->configPropName = "av1C";
break;
#if defined(AVIF_CODEC_AVM)
case AVIF_CODEC_TYPE_AV2:
encoder->data->imageItemType = "av02";
encoder->data->configPropName = "av2C";
break;
#endif
default:
return AVIF_RESULT_NO_CODEC_AVAILABLE;
}
// -----------------------------------------------------------------------
// Map quality and qualityAlpha to quantizer and quantizerAlpha
encoder->data->quantizer = avifQualityToQuantizer(encoder->quality, encoder->minQuantizer, encoder->maxQuantizer);
encoder->data->quantizerAlpha = avifQualityToQuantizer(encoder->qualityAlpha, encoder->minQuantizerAlpha, encoder->maxQuantizerAlpha);
#if defined(AVIF_ENABLE_EXPERIMENTAL_GAIN_MAP)
encoder->data->quantizerGainMap =
avifQualityToQuantizer(encoder->qualityGainMap, AVIF_QUANTIZER_BEST_QUALITY, AVIF_QUANTIZER_WORST_QUALITY);
#endif
// -----------------------------------------------------------------------
// Handle automatic tiling
encoder->data->tileRowsLog2 = AVIF_CLAMP(encoder->tileRowsLog2, 0, 6);
encoder->data->tileColsLog2 = AVIF_CLAMP(encoder->tileColsLog2, 0, 6);
if (encoder->autoTiling) {
// Use as many tiles as allowed by the minimum tile area requirement and impose a maximum
// of 8 tiles.
const int threads = 8;
avifSetTileConfiguration(threads, firstCell->width, firstCell->height, &encoder->data->tileRowsLog2, &encoder->data->tileColsLog2);
}
// -----------------------------------------------------------------------
// All encoder settings are known now. Detect changes.
avifEncoderChanges encoderChanges;
if (!avifEncoderDetectChanges(encoder, &encoderChanges)) {
return AVIF_RESULT_CANNOT_CHANGE_SETTING;
}
avifEncoderBackupSettings(encoder);
// -----------------------------------------------------------------------
if (durationInTimescales == 0) {
durationInTimescales = 1;
}
if (encoder->data->items.count == 0) {
// Make a copy of the first image's metadata (sans pixels) for future writing/validation
AVIF_CHECKRES(avifImageCopy(encoder->data->imageMetadata, firstCell, 0));
#if defined(AVIF_ENABLE_EXPERIMENTAL_GAIN_MAP)
if (hasGainMap) {
AVIF_CHECKRES(avifImageCopyAltImageMetadata(encoder->data->altImageMetadata, encoder->data->imageMetadata));
}
#endif
// Prepare all AV1 items
uint16_t colorItemID;
const uint32_t gridWidth = avifGridWidth(gridCols, firstCell, bottomRightCell);
const uint32_t gridHeight = avifGridHeight(gridRows, firstCell, bottomRightCell);
AVIF_CHECKRES(avifEncoderAddImageItems(encoder, gridCols, gridRows, gridWidth, gridHeight, AVIF_ITEM_COLOR, &colorItemID));
encoder->data->primaryItemID = colorItemID;
encoder->data->alphaPresent = (firstCell->alphaPlane != NULL);
if (encoder->data->alphaPresent && (addImageFlags & AVIF_ADD_IMAGE_FLAG_SINGLE)) {
// If encoding a single image in which the alpha plane exists but is entirely opaque,
// simply skip writing an alpha AV1 payload entirely, as it'll be interpreted as opaque
// and is less bytes.
//
// However, if encoding an image sequence, the first frame's alpha plane being entirely
// opaque could be a false positive for removing the alpha AV1 payload, as it might simply
// be a fade out later in the sequence. This is why avifImageIsOpaque() is only called
// when encoding a single image.
encoder->data->alphaPresent = AVIF_FALSE;
for (uint32_t cellIndex = 0; cellIndex < cellCount; ++cellIndex) {
const avifImage * cellImage = cellImages[cellIndex];
if (!avifImageIsOpaque(cellImage)) {
encoder->data->alphaPresent = AVIF_TRUE;
break;
}
}
}
if (encoder->data->alphaPresent) {
uint16_t alphaItemID;
AVIF_CHECKRES(avifEncoderAddImageItems(encoder, gridCols, gridRows, gridWidth, gridHeight, AVIF_ITEM_ALPHA, &alphaItemID));
avifEncoderItem * alphaItem = avifEncoderDataFindItemByID(encoder->data, alphaItemID);
AVIF_ASSERT_OR_RETURN(alphaItem);
alphaItem->irefType = "auxl";
alphaItem->irefToID = colorItemID;
if (encoder->data->imageMetadata->alphaPremultiplied) {
avifEncoderItem * colorItem = avifEncoderDataFindItemByID(encoder->data, colorItemID);
AVIF_ASSERT_OR_RETURN(colorItem);
colorItem->irefType = "prem";
colorItem->irefToID = alphaItemID;
}
}
#if defined(AVIF_ENABLE_EXPERIMENTAL_GAIN_MAP)
if (firstCell->gainMap && firstCell->gainMap->image) {
avifEncoderItem * toneMappedItem = avifEncoderDataCreateItem(encoder->data,
"tmap",
infeNameGainMap,
/*infeNameSize=*/strlen(infeNameGainMap) + 1,
/*cellIndex=*/0);
if (!avifWriteToneMappedImagePayload(&toneMappedItem->metadataPayload, &firstCell->gainMap->metadata)) {
avifDiagnosticsPrintf(&encoder->diag, "failed to write gain map metadata, some values may be negative or too large");
return AVIF_RESULT_ENCODE_GAIN_MAP_FAILED;
}
// Even though the 'tmap' item is related to the gain map, it represents a color image and its metadata is more similar to the color item.
toneMappedItem->itemCategory = AVIF_ITEM_COLOR;
uint16_t toneMappedItemID = toneMappedItem->id;
AVIF_ASSERT_OR_RETURN(encoder->data->alternativeItemIDs.count == 0);
uint16_t * alternativeItemID = (uint16_t *)avifArrayPush(&encoder->data->alternativeItemIDs);
AVIF_CHECKERR(alternativeItemID != NULL, AVIF_RESULT_OUT_OF_MEMORY);
*alternativeItemID = toneMappedItemID;
alternativeItemID = (uint16_t *)avifArrayPush(&encoder->data->alternativeItemIDs);
AVIF_CHECKERR(alternativeItemID != NULL, AVIF_RESULT_OUT_OF_MEMORY);
*alternativeItemID = colorItemID;
const uint32_t gainMapGridWidth =
avifGridWidth(gridCols, cellImages[0]->gainMap->image, cellImages[gridCols * gridRows - 1]->gainMap->image);
const uint32_t gainMapGridHeight =
avifGridHeight(gridRows, cellImages[0]->gainMap->image, cellImages[gridCols * gridRows - 1]->gainMap->image);
uint16_t gainMapItemID;
AVIF_CHECKRES(
avifEncoderAddImageItems(encoder, gridCols, gridRows, gainMapGridWidth, gainMapGridHeight, AVIF_ITEM_GAIN_MAP, &gainMapItemID));
avifEncoderItem * gainMapItem = avifEncoderDataFindItemByID(encoder->data, gainMapItemID);
AVIF_ASSERT_OR_RETURN(gainMapItem);
gainMapItem->hiddenImage = AVIF_TRUE;
// Set the color item and gain map item's dimgFromID value to point to the tone mapped item.
// The color item shall be first, and the gain map second. avifEncoderFinish() writes the
// dimg item references in item id order, so as long as colorItemID < gainMapItemID, the order
// will be correct.
AVIF_ASSERT_OR_RETURN(colorItemID < gainMapItemID);
avifEncoderItem * colorItem = avifEncoderDataFindItemByID(encoder->data, colorItemID);
AVIF_ASSERT_OR_RETURN(colorItem);
AVIF_ASSERT_OR_RETURN(colorItem->dimgFromID == 0); // Our internal API only allows one dimg value per item.
colorItem->dimgFromID = toneMappedItemID;
gainMapItem->dimgFromID = toneMappedItemID;
}
#endif // AVIF_ENABLE_EXPERIMENTAL_GAIN_MAP
#if defined(AVIF_ENABLE_EXPERIMENTAL_SAMPLE_TRANSFORM)
if (encoder->sampleTransformRecipe == AVIF_SAMPLE_TRANSFORM_BIT_DEPTH_EXTENSION_8B_8B ||
encoder->sampleTransformRecipe == AVIF_SAMPLE_TRANSFORM_BIT_DEPTH_EXTENSION_12B_4B) {
// For now, only 16-bit depth is supported.
AVIF_ASSERT_OR_RETURN(firstCell->depth == 16);
#if defined(AVIF_ENABLE_EXPERIMENTAL_GAIN_MAP)
AVIF_CHECKERR(!firstCell->gainMap, AVIF_RESULT_NOT_IMPLEMENTED); // TODO(yguyon): Implement 16-bit HDR
#endif
AVIF_CHECKRES(avifEncoderCreateBitDepthExtensionItems(encoder, gridCols, gridRows, gridWidth, gridHeight, colorItemID));
} else {
AVIF_CHECKERR(encoder->sampleTransformRecipe == AVIF_SAMPLE_TRANSFORM_NONE, AVIF_RESULT_NOT_IMPLEMENTED);
}
#endif // AVIF_ENABLE_EXPERIMENTAL_SAMPLE_TRANSFORM
// -----------------------------------------------------------------------
// Create metadata items (Exif, XMP)
if (firstCell->exif.size > 0) {
const avifResult result = avifEncoderDataCreateExifItem(encoder->data, &firstCell->exif);
if (result != AVIF_RESULT_OK) {
return result;
}
}
if (firstCell->xmp.size > 0) {
const avifResult result = avifEncoderDataCreateXMPItem(encoder->data, &firstCell->xmp);
if (result != AVIF_RESULT_OK) {
return result;
}
}
} else {
// Another frame in an image sequence, or layer in a layered image
#if defined(AVIF_ENABLE_EXPERIMENTAL_GAIN_MAP)
if (hasGainMap) {
avifDiagnosticsPrintf(&encoder->diag, "gain maps are not supported for image sequences or layered images");
return AVIF_RESULT_NOT_IMPLEMENTED;
}
#endif
const avifImage * imageMetadata = encoder->data->imageMetadata;
// Image metadata that are copied to the configuration property and nclx boxes are not allowed to change.
// If the first image in the sequence had an alpha plane (even if fully opaque), all
// subsequent images must have alpha as well.
if ((imageMetadata->depth != firstCell->depth) || (imageMetadata->yuvFormat != firstCell->yuvFormat) ||
(imageMetadata->yuvRange != firstCell->yuvRange) ||
(imageMetadata->yuvChromaSamplePosition != firstCell->yuvChromaSamplePosition) ||
(imageMetadata->colorPrimaries != firstCell->colorPrimaries) ||
(imageMetadata->transferCharacteristics != firstCell->transferCharacteristics) ||
(imageMetadata->matrixCoefficients != firstCell->matrixCoefficients) ||
(imageMetadata->alphaPremultiplied != firstCell->alphaPremultiplied) ||
(encoder->data->alphaPresent && !firstCell->alphaPlane)) {
return AVIF_RESULT_INCOMPATIBLE_IMAGE;
}
}
if (encoder->data->frames.count == 1) {
// We will be writing an image sequence. When writing the AV1SampleEntry (derived from
// VisualSampleEntry) in the stsd box, we need to cast imageMetadata->width and
// imageMetadata->height to uint16_t:
// class VisualSampleEntry(codingname) extends SampleEntry (codingname){
// ...
// unsigned int(16) width;
// unsigned int(16) height;
// ...
// }
// Check whether it is safe to cast width and height to uint16_t. The maximum width and
// height of an AV1 frame are 65536, which just exceeds uint16_t.
AVIF_ASSERT_OR_RETURN(encoder->data->items.count > 0);
const avifImage * imageMetadata = encoder->data->imageMetadata;
AVIF_CHECKERR(imageMetadata->width <= 65535 && imageMetadata->height <= 65535, AVIF_RESULT_INVALID_ARGUMENT);
}
// -----------------------------------------------------------------------
// Encode AV1 OBUs
for (uint32_t itemIndex = 0; itemIndex < encoder->data->items.count; ++itemIndex) {
avifEncoderItem * item = &encoder->data->items.item[itemIndex];
if (item->codec) {
const avifImage * cellImage = cellImages[item->cellIndex];
avifImage * cellImagePlaceholder = NULL; // May be used as a temporary, modified cellImage. Left as NULL otherwise.
const avifImage * firstCellImage = firstCell;
#if defined(AVIF_ENABLE_EXPERIMENTAL_GAIN_MAP)
if (item->itemCategory == AVIF_ITEM_GAIN_MAP) {
AVIF_ASSERT_OR_RETURN(cellImage->gainMap && cellImage->gainMap->image);
cellImage = cellImage->gainMap->image;
AVIF_ASSERT_OR_RETURN(firstCell->gainMap && firstCell->gainMap->image);
firstCellImage = firstCell->gainMap->image;
}
#endif
if ((cellImage->width != firstCellImage->width) || (cellImage->height != firstCellImage->height)) {
// Pad the right-most and/or bottom-most tiles so that all tiles share the same dimensions.
cellImagePlaceholder = avifImageCreateEmpty();
AVIF_CHECKERR(cellImagePlaceholder, AVIF_RESULT_OUT_OF_MEMORY);
const avifResult result =
avifImageCopyAndPad(cellImagePlaceholder, cellImage, firstCellImage->width, firstCellImage->height);
if (result != AVIF_RESULT_OK) {
avifImageDestroy(cellImagePlaceholder);
return result;
}
cellImage = cellImagePlaceholder;
}
const avifBool isAlpha = avifIsAlpha(item->itemCategory);
int quantizer = isAlpha ? encoder->data->quantizerAlpha
#if defined(AVIF_ENABLE_EXPERIMENTAL_GAIN_MAP)
: (item->itemCategory == AVIF_ITEM_GAIN_MAP) ? encoder->data->quantizerGainMap
#endif
: encoder->data->quantizer;
#if defined(AVIF_ENABLE_EXPERIMENTAL_SAMPLE_TRANSFORM)
// Remember original quantizer values in case they change, to reset them afterwards.
int * encoderMinQuantizer = isAlpha ? &encoder->minQuantizerAlpha : &encoder->minQuantizer;
int * encoderMaxQuantizer = isAlpha ? &encoder->maxQuantizerAlpha : &encoder->maxQuantizer;
const int originalMinQuantizer = *encoderMinQuantizer;
const int originalMaxQuantizer = *encoderMaxQuantizer;
if (encoder->sampleTransformRecipe != AVIF_SAMPLE_TRANSFORM_NONE) {
if ((encoder->sampleTransformRecipe == AVIF_SAMPLE_TRANSFORM_BIT_DEPTH_EXTENSION_8B_8B ||
encoder->sampleTransformRecipe == AVIF_SAMPLE_TRANSFORM_BIT_DEPTH_EXTENSION_12B_4B) &&
(item->itemCategory == AVIF_ITEM_COLOR || item->itemCategory == AVIF_ITEM_ALPHA)) {
// Encoding the least significant bits of a sample does not make any sense if the
// other bits are lossily compressed. Encode the most significant bits losslessly.
quantizer = AVIF_QUANTIZER_LOSSLESS;
*encoderMinQuantizer = AVIF_QUANTIZER_LOSSLESS;
*encoderMaxQuantizer = AVIF_QUANTIZER_LOSSLESS;
if (!avifEncoderDetectChanges(encoder, &encoderChanges)) {
assert(AVIF_FALSE);
}
}
// Replace cellImage by the first or second input to the AVIF_ITEM_SAMPLE_TRANSFORM derived image item.
const avifBool itemWillBeEncodedLosslessly = (quantizer == AVIF_QUANTIZER_LOSSLESS);
avifImage * sampleTransformedImage = NULL;
if (cellImagePlaceholder) {
avifImageDestroy(cellImagePlaceholder); // Replaced by sampleTransformedImage.
cellImagePlaceholder = NULL;
}
AVIF_CHECKRES(
avifEncoderCreateBitDepthExtensionImage(encoder, item, itemWillBeEncodedLosslessly, cellImage, &sampleTransformedImage));
cellImagePlaceholder = sampleTransformedImage; // Transfer ownership.
cellImage = cellImagePlaceholder;
}
#endif // AVIF_ENABLE_EXPERIMENTAL_SAMPLE_TRANSFORM
// If alpha channel is present, set disableLaggedOutput to AVIF_TRUE. If the encoder supports it, this enables
// avifEncoderDataShouldForceKeyframeForAlpha to force a keyframe in the alpha channel whenever a keyframe has been
// encoded in the color channel for animated images.
avifResult encodeResult = item->codec->encodeImage(item->codec,
encoder,
cellImage,
isAlpha,
encoder->data->tileRowsLog2,
encoder->data->tileColsLog2,
quantizer,
encoderChanges,
/*disableLaggedOutput=*/encoder->data->alphaPresent,
addImageFlags,
item->encodeOutput);
#if defined(AVIF_ENABLE_EXPERIMENTAL_SAMPLE_TRANSFORM)
// Revert quality settings if they changed.
if (*encoderMinQuantizer != originalMinQuantizer || *encoderMaxQuantizer != originalMaxQuantizer) {
avifEncoderBackupSettings(encoder); // Remember last encoding settings for next avifEncoderDetectChanges().
*encoderMinQuantizer = originalMinQuantizer;
*encoderMaxQuantizer = originalMaxQuantizer;
}
#endif // AVIF_ENABLE_EXPERIMENTAL_SAMPLE_TRANSFORM
if (cellImagePlaceholder) {
avifImageDestroy(cellImagePlaceholder);
}
if (encodeResult == AVIF_RESULT_UNKNOWN_ERROR) {
encodeResult = avifGetErrorForItemCategory(item->itemCategory);
}
AVIF_CHECKRES(encodeResult);
if (itemIndex == 0 && avifEncoderDataShouldForceKeyframeForAlpha(encoder->data, item, addImageFlags)) {
addImageFlags |= AVIF_ADD_IMAGE_FLAG_FORCE_KEYFRAME;
}
}
}
avifCodecSpecificOptionsClear(encoder->csOptions);
avifEncoderFrame * frame = (avifEncoderFrame *)avifArrayPush(&encoder->data->frames);
AVIF_CHECKERR(frame != NULL, AVIF_RESULT_OUT_OF_MEMORY);
frame->durationInTimescales = durationInTimescales;
return AVIF_RESULT_OK;
}
avifResult avifEncoderAddImage(avifEncoder * encoder, const avifImage * image, uint64_t durationInTimescales, avifAddImageFlags addImageFlags)
{
avifDiagnosticsClearError(&encoder->diag);
return avifEncoderAddImageInternal(encoder, 1, 1, &image, durationInTimescales, addImageFlags);
}
avifResult avifEncoderAddImageGrid(avifEncoder * encoder,
uint32_t gridCols,
uint32_t gridRows,
const avifImage * const * cellImages,
avifAddImageFlags addImageFlags)
{
avifDiagnosticsClearError(&encoder->diag);
if ((gridCols == 0) || (gridCols > 256) || (gridRows == 0) || (gridRows > 256)) {
return AVIF_RESULT_INVALID_IMAGE_GRID;
}
if (encoder->extraLayerCount == 0) {
addImageFlags |= AVIF_ADD_IMAGE_FLAG_SINGLE; // image grids cannot be image sequences
}
return avifEncoderAddImageInternal(encoder, gridCols, gridRows, cellImages, 1, addImageFlags);
}
static size_t avifEncoderFindExistingChunk(avifRWStream * s, size_t mdatStartOffset, const uint8_t * data, size_t size)
{
const size_t mdatCurrentOffset = avifRWStreamOffset(s);
const size_t mdatSearchSize = mdatCurrentOffset - mdatStartOffset;
if (mdatSearchSize < size) {
return 0;
}
const size_t mdatEndSearchOffset = mdatCurrentOffset - size;
for (size_t searchOffset = mdatStartOffset; searchOffset <= mdatEndSearchOffset; ++searchOffset) {
if (!memcmp(data, &s->raw->data[searchOffset], size)) {
return searchOffset;
}
}
return 0;
}
static avifResult avifEncoderWriteMediaDataBox(avifEncoder * encoder,
avifRWStream * s,
avifEncoderItemReferenceArray * layeredColorItems,
avifEncoderItemReferenceArray * layeredAlphaItems)
{
encoder->ioStats.colorOBUSize = 0;
encoder->ioStats.alphaOBUSize = 0;
encoder->data->gainMapSizeBytes = 0;
avifBoxMarker mdat;
AVIF_CHECKRES(avifRWStreamWriteBox(s, "mdat", AVIF_BOX_SIZE_TBD, &mdat));
const size_t mdatStartOffset = avifRWStreamOffset(s);
for (uint32_t itemPasses = 0; itemPasses < 3; ++itemPasses) {
// Use multiple passes to pack in the following order:
// * Pass 0: metadata (Exif/XMP)
// * Pass 1: alpha, gain map (AV1)
// * Pass 2: all other item data (AV1 color)
//
// See here for the discussion on alpha coming before color:
// https://github.com/AOMediaCodec/libavif/issues/287
//
// Exif and XMP are packed first as they're required to be fully available
// by avifDecoderParse() before it returns AVIF_RESULT_OK, unless ignoreXMP
// and ignoreExif are enabled.
//
const avifBool metadataPass = (itemPasses == 0);
const avifBool alphaAndGainMapPass = (itemPasses == 1);
for (uint32_t itemIndex = 0; itemIndex < encoder->data->items.count; ++itemIndex) {
avifEncoderItem * item = &encoder->data->items.item[itemIndex];
if ((item->metadataPayload.size == 0) && (item->encodeOutput->samples.count == 0)) {
// this item has nothing for the mdat box
continue;
}
const avifBool isMetadata = !memcmp(item->type, "mime", 4) || !memcmp(item->type, "Exif", 4);
if (metadataPass != isMetadata) {
// only process metadata (XMP/Exif) payloads when metadataPass is true
continue;
}
const avifBool isAlpha = avifIsAlpha(item->itemCategory);
const avifBool isAlphaOrGainMap = isAlpha
#if defined(AVIF_ENABLE_EXPERIMENTAL_GAIN_MAP)
|| item->itemCategory == AVIF_ITEM_GAIN_MAP
#endif
;
if (alphaAndGainMapPass != isAlphaOrGainMap) {
// only process alpha payloads when alphaPass is true
continue;
}
if ((encoder->extraLayerCount > 0) && (item->encodeOutput->samples.count > 0)) {
// Interleave - Pick out AV1 items and interleave them later.
// We always interleave all AV1 items for layered images.
AVIF_ASSERT_OR_RETURN(item->encodeOutput->samples.count == item->mdatFixups.count);
avifEncoderItemReference * ref =
(avifEncoderItemReference *)avifArrayPush(isAlpha ? layeredAlphaItems : layeredColorItems);
AVIF_CHECKERR(ref != NULL, AVIF_RESULT_OUT_OF_MEMORY);
*ref = item;
continue;
}
size_t chunkOffset = 0;
// Deduplication - See if an identical chunk to this has already been written.
// Doing it when item->encodeOutput->samples.count > 1 would require contiguous memory.
if (item->encodeOutput->samples.count == 1) {
avifEncodeSample * sample = &item->encodeOutput->samples.sample[0];
chunkOffset = avifEncoderFindExistingChunk(s, mdatStartOffset, sample->data.data, sample->data.size);
} else if (item->encodeOutput->samples.count == 0) {
chunkOffset = avifEncoderFindExistingChunk(s, mdatStartOffset, item->metadataPayload.data, item->metadataPayload.size);
}
if (!chunkOffset) {
// We've never seen this chunk before; write it out
chunkOffset = avifRWStreamOffset(s);
if (item->encodeOutput->samples.count > 0) {
for (uint32_t sampleIndex = 0; sampleIndex < item->encodeOutput->samples.count; ++sampleIndex) {
avifEncodeSample * sample = &item->encodeOutput->samples.sample[sampleIndex];
AVIF_CHECKRES(avifRWStreamWrite(s, sample->data.data, sample->data.size));
if (isAlpha) {
encoder->ioStats.alphaOBUSize += sample->data.size;
} else if (item->itemCategory == AVIF_ITEM_COLOR) {
encoder->ioStats.colorOBUSize += sample->data.size;
#if defined(AVIF_ENABLE_EXPERIMENTAL_GAIN_MAP)
} else if (item->itemCategory == AVIF_ITEM_GAIN_MAP) {
encoder->data->gainMapSizeBytes += sample->data.size;
#endif
}
}
} else {
AVIF_CHECKRES(avifRWStreamWrite(s, item->metadataPayload.data, item->metadataPayload.size));
}
}
for (uint32_t fixupIndex = 0; fixupIndex < item->mdatFixups.count; ++fixupIndex) {
avifOffsetFixup * fixup = &item->mdatFixups.fixup[fixupIndex];
size_t prevOffset = avifRWStreamOffset(s);
avifRWStreamSetOffset(s, fixup->offset);
AVIF_CHECKRES(avifRWStreamWriteU32(s, (uint32_t)chunkOffset));
avifRWStreamSetOffset(s, prevOffset);
}
}
}
uint32_t layeredItemCount = AVIF_MAX(layeredColorItems->count, layeredAlphaItems->count);
if (layeredItemCount > 0) {
// Interleave samples of all AV1 items.
// We first write the first layer of all items,
// in which we write first layer of each cell,
// in which we write alpha first and then color.
avifBool hasMoreSample;
uint32_t layerIndex = 0;
do {
hasMoreSample = AVIF_FALSE;
for (uint32_t itemIndex = 0; itemIndex < layeredItemCount; ++itemIndex) {
for (int samplePass = 0; samplePass < 2; ++samplePass) {
// Alpha coming before color
avifEncoderItemReferenceArray * currentItems = (samplePass == 0) ? layeredAlphaItems : layeredColorItems;
if (itemIndex >= currentItems->count) {
continue;
}
// TODO: Offer the ability for a user to specify which grid cell should be written first.
avifEncoderItem * item = currentItems->ref[itemIndex];
if (item->encodeOutput->samples.count <= layerIndex) {
// We've already written all samples of this item
continue;
} else if (item->encodeOutput->samples.count > layerIndex + 1) {
hasMoreSample = AVIF_TRUE;
}
avifRWData * data = &item->encodeOutput->samples.sample[layerIndex].data;
size_t chunkOffset = avifEncoderFindExistingChunk(s, mdatStartOffset, data->data, data->size);
if (!chunkOffset) {
// We've never seen this chunk before; write it out
chunkOffset = avifRWStreamOffset(s);
AVIF_CHECKRES(avifRWStreamWrite(s, data->data, data->size));
if (samplePass == 0) {
encoder->ioStats.alphaOBUSize += data->size;
} else {
encoder->ioStats.colorOBUSize += data->size;
}
}
size_t prevOffset = avifRWStreamOffset(s);
avifRWStreamSetOffset(s, item->mdatFixups.fixup[layerIndex].offset);
AVIF_CHECKRES(avifRWStreamWriteU32(s, (uint32_t)chunkOffset));
avifRWStreamSetOffset(s, prevOffset);
}
}
++layerIndex;
} while (hasMoreSample);
AVIF_ASSERT_OR_RETURN(layerIndex <= AVIF_MAX_AV1_LAYER_COUNT);
}
avifRWStreamFinishBox(s, mdat);
return AVIF_RESULT_OK;
}
static avifResult avifWriteAltrGroup(avifRWStream * s, const avifEncoderItemIdArray * itemIDs)
{
avifBoxMarker grpl;
AVIF_CHECKRES(avifRWStreamWriteBox(s, "grpl", AVIF_BOX_SIZE_TBD, &grpl));
avifBoxMarker altr;
AVIF_CHECKRES(avifRWStreamWriteFullBox(s, "altr", AVIF_BOX_SIZE_TBD, 0, 0, &altr));
AVIF_CHECKRES(avifRWStreamWriteU32(s, 1)); // unsigned int(32) group_id;
AVIF_CHECKRES(avifRWStreamWriteU32(s, (uint32_t)itemIDs->count)); // unsigned int(32) num_entities_in_group;
for (uint32_t i = 0; i < itemIDs->count; ++i) {
AVIF_CHECKRES(avifRWStreamWriteU32(s, (uint32_t)itemIDs->item_id[i])); // unsigned int(32) entity_id;
}
avifRWStreamFinishBox(s, altr);
avifRWStreamFinishBox(s, grpl);
return AVIF_RESULT_OK;
}
#if defined(AVIF_ENABLE_EXPERIMENTAL_METAV1)
// Returns true if the image can be encoded with a slim MetaBox with version 1
// instead of a full regular MetaBox with version 0.
static avifBool avifEncoderIsMetaBoxV1Compatible(const avifEncoder * encoder)
{
// The MetaBox with version 1 ("mif3" brand) only supports non-layered, still images.
if (encoder->extraLayerCount || (encoder->data->frames.count != 1)) {
return AVIF_FALSE;
}
#if defined(AVIF_ENABLE_EXPERIMENTAL_SAMPLE_TRANSFORM)
if (encoder->sampleTransformRecipe != AVIF_SAMPLE_TRANSFORM_NONE) {
return AVIF_FALSE;
}
#endif
if (encoder->data->imageMetadata->width > (1 << 15) || encoder->data->imageMetadata->height > (1 << 15)) {
return AVIF_FALSE;
}
if (encoder->data->imageMetadata->icc.size > (1 << 20) || encoder->data->imageMetadata->exif.size > (1 << 20) ||
encoder->data->imageMetadata->xmp.size > (1 << 20)) {
return AVIF_FALSE;
}
// 4:4:4, 4:2:2, 4:2:0 and 4:0:0 are supported by a MetaBox with version 1.
if (encoder->data->imageMetadata->yuvFormat == AVIF_PIXEL_FORMAT_NONE) {
return AVIF_FALSE;
}
if (encoder->data->imageMetadata->colorPrimaries > 255 || encoder->data->imageMetadata->transferCharacteristics > 255 ||
encoder->data->imageMetadata->matrixCoefficients > 255) {
return AVIF_FALSE;
}
const avifEncoderItem * colorItem = NULL;
for (uint32_t itemIndex = 0; itemIndex < encoder->data->items.count; ++itemIndex) {
avifEncoderItem * item = &encoder->data->items.item[itemIndex];
// Grids are not supported by a MetaBox with version 1.
if (item->gridCols || item->gridRows) {
return AVIF_FALSE;
}
if (item->id == encoder->data->primaryItemID) {
assert(!colorItem);
colorItem = item;
// main_item_data_size_minus_one so 2^28 inclusive.
if (item->encodeOutput->samples.count != 1 || item->encodeOutput->samples.sample[0].data.size > (1 << 28)) {
return AVIF_FALSE;
}
continue; // The primary item can be stored in the MetaBox with version 1.
}
if (item->itemCategory == AVIF_ITEM_ALPHA && item->irefToID == encoder->data->primaryItemID) {
// alpha_item_data_size so 2^28 exclusive.
if (item->encodeOutput->samples.count != 1 || item->encodeOutput->samples.sample[0].data.size >= (1 << 28)) {
return AVIF_FALSE;
}
continue; // The alpha auxiliary item can be stored in the MetaBox with version 1.
}
if (!memcmp(item->type, "mime", 4) && !memcmp(item->infeName, "XMP", item->infeNameSize)) {
assert(item->metadataPayload.size == encoder->data->imageMetadata->xmp.size);
continue; // XMP metadata can be stored in the MetaBox with version 1.
}
if (!memcmp(item->type, "Exif", 4) && !memcmp(item->infeName, "Exif", item->infeNameSize)) {
assert(item->metadataPayload.size == encoder->data->imageMetadata->exif.size + 4);
const uint32_t exif_tiff_header_offset = *(uint32_t *)item->metadataPayload.data;
if (exif_tiff_header_offset != 0) {
return AVIF_FALSE;
}
continue; // Exif metadata can be stored in the MetaBox with version 1 if exif_tiff_header_offset is 0.
}
// Items besides the colorItem, the alphaItem and Exif/XMP/ICC
// metadata are not directly supported by the MetaBox with version 1.
return AVIF_FALSE;
}
// A primary item is necessary.
if (!colorItem) {
return AVIF_FALSE;
}
return AVIF_TRUE;
}
static avifResult avifEncoderWriteMetaBoxV1(avifEncoder * encoder, avifRWStream * s);
static avifResult avifEncoderWriteFileTypeBoxAndMetaBoxV1(avifEncoder * encoder, avifRWData * output)
{
avifRWStream s;
avifRWStreamStart(&s, output);
avifBoxMarker ftyp;
AVIF_CHECKRES(avifRWStreamWriteBox(&s, "ftyp", AVIF_BOX_SIZE_TBD, &ftyp));
AVIF_CHECKRES(avifRWStreamWriteChars(&s, "mif3", 4)); // unsigned int(32) major_brand;
AVIF_CHECKRES(avifRWStreamWriteChars(&s, "avif", 4)); // unsigned int(32) minor_version;
// unsigned int(32) compatible_brands[];
avifRWStreamFinishBox(&s, ftyp);
AVIF_CHECKRES(avifEncoderWriteMetaBoxV1(encoder, &s));
avifRWStreamFinishWrite(&s);
return AVIF_RESULT_OK;
}
static avifResult avifEncoderWriteMetaBoxV1(avifEncoder * encoder, avifRWStream * s)
{
const avifEncoderItem * colorItem = NULL;
const avifEncoderItem * alphaItem = NULL;
for (uint32_t itemIndex = 0; itemIndex < encoder->data->items.count; ++itemIndex) {
avifEncoderItem * item = &encoder->data->items.item[itemIndex];
if (item->id == encoder->data->primaryItemID) {
AVIF_ASSERT_OR_RETURN(!colorItem);
colorItem = item;
} else if (item->itemCategory == AVIF_ITEM_ALPHA && item->irefToID == encoder->data->primaryItemID) {
AVIF_ASSERT_OR_RETURN(!alphaItem);
alphaItem = item;
}
}
AVIF_ASSERT_OR_RETURN(colorItem);
const avifRWData * colorData = &colorItem->encodeOutput->samples.sample[0].data;
const avifRWData * alphaData = alphaItem ? &alphaItem->encodeOutput->samples.sample[0].data : NULL;
const avifImage * const image = encoder->data->imageMetadata;
const avifBool hasAlpha = alphaItem != NULL;
const avifBool alphaIsPremultiplied = encoder->data->imageMetadata->alphaPremultiplied;
const avifBool hasHdr = AVIF_FALSE; // Not implemented.
const avifBool hasIcc = image->icc.size != 0;
const uint32_t chromaSubsampling = image->yuvFormat == AVIF_PIXEL_FORMAT_YUV400 ? 0
: image->yuvFormat == AVIF_PIXEL_FORMAT_YUV420 ? 1
: image->yuvFormat == AVIF_PIXEL_FORMAT_YUV422 ? 2
: 3;
const avifColorPrimaries defaultColorPrimaries = hasIcc ? AVIF_COLOR_PRIMARIES_UNSPECIFIED : AVIF_COLOR_PRIMARIES_BT709;
const avifTransferCharacteristics defaultTransferCharacteristics = hasIcc ? AVIF_TRANSFER_CHARACTERISTICS_UNSPECIFIED
: AVIF_TRANSFER_CHARACTERISTICS_SRGB;
const avifMatrixCoefficients defaultMatrixCoefficients = chromaSubsampling == 0 ? AVIF_MATRIX_COEFFICIENTS_UNSPECIFIED
: AVIF_MATRIX_COEFFICIENTS_BT601;
const avifBool hasExplicitCicp = image->colorPrimaries != defaultColorPrimaries ||
image->transferCharacteristics != defaultTransferCharacteristics ||
image->matrixCoefficients != defaultMatrixCoefficients;
const avifBool fullRange = image->yuvRange == AVIF_RANGE_FULL;
const uint32_t pixelFormat = image->depth == 8 ? AVIF_METAV1_PIXEL_FORMAT_UINT8
: image->depth == 10 ? AVIF_METAV1_PIXEL_FORMAT_UINT10
: AVIF_METAV1_PIXEL_FORMAT_UINT12;
// 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).
if (image->yuvFormat != AVIF_PIXEL_FORMAT_YUV420 && image->yuvChromaSamplePosition != AVIF_CHROMA_SAMPLE_POSITION_UNKNOWN) {
avifDiagnosticsPrintf(&encoder->diag,
"YUV chroma sample position %d is only supported with 4:2:0 YUV format in AV1",
image->yuvChromaSamplePosition);
return AVIF_RESULT_INVALID_ARGUMENT;
}
// For the YUV 4:2:0 format, assume centered sample position unless specified otherwise.
// This is consistent with the behavior in read.c.
const avifBool isHorizontallyCentered = image->yuvFormat == AVIF_PIXEL_FORMAT_YUV420 &&
image->yuvChromaSamplePosition != AVIF_CHROMA_SAMPLE_POSITION_VERTICAL &&
image->yuvChromaSamplePosition != AVIF_CHROMA_SAMPLE_POSITION_COLOCATED;
const avifBool isVerticallyCentered = image->yuvFormat == AVIF_PIXEL_FORMAT_YUV420 &&
image->yuvChromaSamplePosition != AVIF_CHROMA_SAMPLE_POSITION_COLOCATED;
const uint32_t orientation = avifImageIrotImirToExifOrientation(image) - 1;
const avifBool hasExplicitCodecTypes = AVIF_FALSE; // 'av01' and 'av1C' known from 'avif' minor_version field of FileTypeBox.
const uint32_t dimensionSize = image->width <= (1 << 7) && image->height <= (1 << 7) ? 7 : 15;
const uint32_t codecConfigSize = 4; // 'av1C' always uses 4 bytes.
const uint32_t codecConfigSizeSize = codecConfigSize < (1 << 3) ? 3 : 12;
const uint32_t itemDataSizeSize = colorData->size <= (1 << 15) && (!alphaData || alphaData->size < (1 << 15)) ? 15 : 28;
const uint32_t metadataSizeSize =
image->icc.size <= (1 << 10) && image->exif.size <= (1 << 10) && image->xmp.size <= (1 << 10) ? 10 : 20;
uint32_t flags = 0;
flags |= alphaItem ? 0x000001 : 0; // has_alpha
flags |= alphaIsPremultiplied ? 0x000002 : 0; // alpha_is_premultiplied
flags |= hasHdr ? 0x000004 : 0; // has_hdr
flags |= hasExplicitCicp ? 0x000008 : 0; // has_explicit_cicp
flags |= hasIcc ? 0x000010 : 0; // has_icc
flags |= image->exif.size ? 0x000020 : 0; // has_exif
flags |= image->xmp.size ? 0x000040 : 0; // has_xmp
flags |= fullRange ? 0x000080 : 0; // full_range
flags |= pixelFormat << 8; // pixel_format (4 bits)
flags |= chromaSubsampling << 12; // chroma_subsampling (2 bits)
flags |= isHorizontallyCentered ? 0x004000 : 0; // is_horizontally_centered
flags |= isVerticallyCentered ? 0x008000 : 0; // is_vertically_centered
flags |= orientation << 16; // orientation (3 bits)
flags |= hasExplicitCodecTypes ? 0x080000 : 0; // has_explicit_codec_types
flags |= dimensionSize == 7 ? 0x100000 : 0; // dimension_size
flags |= codecConfigSizeSize == 3 ? 0x200000 : 0; // codec_config_size_size
flags |= itemDataSizeSize == 15 ? 0x400000 : 0; // item_data_size_size
flags |= metadataSizeSize == 10 ? 0x800000 : 0; // metadata_size_size
avifBoxMarker meta;
AVIF_CHECKRES(avifRWStreamWriteFullBox(s, "meta", AVIF_BOX_SIZE_TBD, /*version=*/1, flags, &meta));
AVIF_CHECKRES(avifRWStreamWriteBits(s, image->width - 1, dimensionSize)); // unsigned int(dimension_size) width_minus_one;
AVIF_CHECKRES(avifRWStreamWriteBits(s, image->height - 1, dimensionSize)); // unsigned int(dimension_size) height_minus_one;
if (hasIcc) {
AVIF_CHECKRES(avifRWStreamWriteBits(s, (uint32_t)image->icc.size - 1, metadataSizeSize)); // unsigned int(metadata_size_size) icc_data_size_minus_one;
}
if (hasExplicitCicp) {
AVIF_CHECKRES(avifRWStreamWriteBits(s, image->colorPrimaries, 8)); // bit(8) colour_primaries;
AVIF_CHECKRES(avifRWStreamWriteBits(s, image->transferCharacteristics, 8)); // bit(8) transfer_characteristics;
}
if (chromaSubsampling == 0) {
AVIF_CHECKERR(image->matrixCoefficients == AVIF_MATRIX_COEFFICIENTS_UNSPECIFIED, AVIF_RESULT_ENCODE_COLOR_FAILED);
} else if (hasExplicitCicp) {
AVIF_CHECKRES(avifRWStreamWriteBits(s, image->matrixCoefficients, 8)); // bit(8) matrix_coefficients;
}
AVIF_CHECKRES(avifRWStreamWriteBits(s, codecConfigSize, codecConfigSizeSize)); // unsigned int(codec_config_size_size) main_item_codec_config_size;
AVIF_CHECKRES(avifRWStreamWriteBits(s, (uint32_t)colorData->size - 1, itemDataSizeSize)); // unsigned int(item_data_size_size) main_item_data_size_minus_one;
if (hasAlpha) {
AVIF_CHECKRES(avifRWStreamWriteBits(s, (uint32_t)alphaData->size, itemDataSizeSize)); // unsigned int(item_data_size_size) alpha_item_data_size;
if (alphaData->size != 0) {
AVIF_CHECKRES(avifRWStreamWriteBits(s, codecConfigSize, codecConfigSizeSize)); // 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;
}
if (image->exif.size) {
AVIF_CHECKRES(avifRWStreamWriteBits(s, (uint32_t)image->exif.size - 1, metadataSizeSize)); // unsigned int(metadata_size_size) exif_data_size_minus_one;
}
if (image->xmp.size) {
AVIF_CHECKRES(avifRWStreamWriteBits(s, (uint32_t)image->xmp.size - 1, metadataSizeSize)); // unsigned int(metadata_size_size) xmp_data_size_minus_one;
}
// Padding to align with whole bytes if necessary.
if (s->numUsedBitsInPartialByte != 0) {
AVIF_CHECKRES(avifRWStreamWriteBits(s, 0, 8 - s->numUsedBitsInPartialByte));
}
const size_t headerSize = avifRWStreamOffset(s);
// Codec configs
if (hasAlpha) {
AVIF_CHECKRES(writeCodecConfig(s, &alphaItem->av1C)); // 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];
AVIF_CHECKRES(writeCodecConfig(s, &colorItem->av1C)); // unsigned int(8) main_item_codec_config[main_item_codec_config_size];
// Color profiles
if (image->icc.size) {
AVIF_CHECKRES(avifRWStreamWrite(s, image->icc.data, image->icc.size)); // unsigned int(8) icc_data[icc_data_size_minus_one + 1];
}
// 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];
// Encoded samples
if (hasAlpha) {
AVIF_CHECKRES(avifRWStreamWrite(s, alphaData->data, alphaData->size)); // unsigned int(8) alpha_item_data[alpha_item_data_size];
}
// if (has_hdr && has_gainmap && gainmap_item_data_size > 0)
// unsigned int(8) gainmap_item_data[gainmap_item_data_size];
AVIF_CHECKRES(avifRWStreamWrite(s, colorData->data, colorData->size)); // unsigned int(8) main_item_data[main_item_data_size_minus_one + 1];
// Metadata
if (image->exif.size) {
AVIF_CHECKRES(avifRWStreamWrite(s, image->exif.data, image->exif.size)); // unsigned int(8) exif_data[exif_data_size_minus_one + 1];
}
if (image->xmp.size) {
AVIF_CHECKRES(avifRWStreamWrite(s, image->xmp.data, image->xmp.size)); // unsigned int(8) xmp_data[xmp_data_size_minus_one + 1];
}
AVIF_ASSERT_OR_RETURN(avifRWStreamOffset(s) - headerSize == (hasAlpha ? codecConfigSize : 0) + codecConfigSize +
image->icc.size + (hasAlpha ? alphaData->size : 0) +
colorData->size + image->exif.size + image->xmp.size);
avifRWStreamFinishBox(s, meta);
return AVIF_RESULT_OK;
}
#endif // AVIF_ENABLE_EXPERIMENTAL_METAV1
static avifResult avifRWStreamWriteProperties(avifItemPropertyDedup * const dedup,
avifRWStream * const s,
const avifEncoder * const encoder,
const avifImage * const imageMetadata,
const avifImage * const altImageMetadata)
{
for (uint32_t itemIndex = 0; itemIndex < encoder->data->items.count; ++itemIndex) {
avifEncoderItem * item = &encoder->data->items.item[itemIndex];
const avifBool isGrid = (item->gridCols > 0);
// Whether there is ipma to write for this item.
avifBool hasIpmaToWrite = item->codec || isGrid;
#if defined(AVIF_ENABLE_EXPERIMENTAL_GAIN_MAP)
const avifBool isToneMappedImage = !memcmp(item->type, "tmap", 4);
if (isToneMappedImage) {
hasIpmaToWrite = AVIF_TRUE;
}
#endif
#if defined(AVIF_ENABLE_EXPERIMENTAL_SAMPLE_TRANSFORM)
const avifBool isSampleTransformImage = !memcmp(item->type, "sato", 4);
if (isSampleTransformImage) {
hasIpmaToWrite = AVIF_TRUE;
}
#endif
memset(&item->ipma, 0, sizeof(item->ipma));