blob: effaa6b39f1e97cefbf5c263a6088e01a38a8071 [file] [log] [blame]
// Copyright 2020 Joe Drago. All rights reserved.
// SPDX-License-Identifier: BSD-2-Clause
#include "avifpng.h"
#include "avifutil.h"
#include "png.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
// See libpng-manual.txt, section XI.
#if PNG_LIBPNG_VER_MAJOR > 1 || (PNG_LIBPNG_VER_MAJOR == 1 && PNG_LIBPNG_VER_MINOR >= 5)
typedef png_bytep png_iccp_datap;
#else
typedef png_charp png_iccp_datap;
#endif
// Note on setjmp() and volatile variables:
//
// K & R, The C Programming Language 2nd Ed, p. 254 says:
// ... Accessible objects have the values they had when longjmp was called,
// except that non-volatile automatic variables in the function calling setjmp
// become undefined if they were changed after the setjmp call.
//
// Therefore, 'rowPointers' is declared as volatile. 'rgb' should be declared as
// volatile, but doing so would be inconvenient (try it) and since it is a
// struct, the compiler is unlikely to put it in a register. 'readResult' and
// 'writeResult' do not need to be declared as volatile because they are not
// modified between setjmp and longjmp. But GCC's -Wclobbered warning may have
// trouble figuring that out, so we preemptively declare them as volatile.
avifBool avifPNGRead(const char * inputFilename, avifImage * avif, avifPixelFormat requestedFormat, uint32_t requestedDepth, uint32_t * outPNGDepth)
{
volatile avifBool readResult = AVIF_FALSE;
png_structp png = NULL;
png_infop info = NULL;
png_bytep * volatile rowPointers = NULL;
avifRGBImage rgb;
memset(&rgb, 0, sizeof(avifRGBImage));
FILE * f = fopen(inputFilename, "rb");
if (!f) {
fprintf(stderr, "Can't open PNG file for read: %s\n", inputFilename);
goto cleanup;
}
uint8_t header[8];
size_t bytesRead = fread(header, 1, 8, f);
if (bytesRead != 8) {
fprintf(stderr, "Can't read PNG header: %s\n", inputFilename);
goto cleanup;
}
if (png_sig_cmp(header, 0, 8)) {
fprintf(stderr, "Not a PNG: %s\n", inputFilename);
goto cleanup;
}
png = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
if (!png) {
fprintf(stderr, "Cannot init libpng (png): %s\n", inputFilename);
goto cleanup;
}
info = png_create_info_struct(png);
if (!info) {
fprintf(stderr, "Cannot init libpng (info): %s\n", inputFilename);
goto cleanup;
}
if (setjmp(png_jmpbuf(png))) {
fprintf(stderr, "Error reading PNG: %s\n", inputFilename);
goto cleanup;
}
png_init_io(png, f);
png_set_sig_bytes(png, 8);
png_read_info(png, info);
char * iccpProfileName = NULL;
int iccpCompression = 0;
unsigned char * iccpData = NULL;
png_uint_32 iccpDataLen = 0;
if (png_get_iCCP(png, info, &iccpProfileName, &iccpCompression, (png_iccp_datap *)&iccpData, &iccpDataLen) == PNG_INFO_iCCP) {
avifImageSetProfileICC(avif, iccpData, iccpDataLen);
}
int rawWidth = png_get_image_width(png, info);
int rawHeight = png_get_image_height(png, info);
png_byte rawColorType = png_get_color_type(png, info);
png_byte rawBitDepth = png_get_bit_depth(png, info);
if (rawColorType == PNG_COLOR_TYPE_PALETTE) {
png_set_palette_to_rgb(png);
}
if ((rawColorType == PNG_COLOR_TYPE_GRAY) && (rawBitDepth < 8)) {
png_set_expand_gray_1_2_4_to_8(png);
}
if (png_get_valid(png, info, PNG_INFO_tRNS)) {
png_set_tRNS_to_alpha(png);
}
if ((rawColorType == PNG_COLOR_TYPE_RGB) || (rawColorType == PNG_COLOR_TYPE_GRAY) || (rawColorType == PNG_COLOR_TYPE_PALETTE)) {
png_set_filler(png, 0xFFFF, PNG_FILLER_AFTER);
}
if ((rawColorType == PNG_COLOR_TYPE_GRAY) || (rawColorType == PNG_COLOR_TYPE_GRAY_ALPHA)) {
png_set_gray_to_rgb(png);
}
int imgBitDepth = 8;
if (rawBitDepth == 16) {
png_set_swap(png);
imgBitDepth = 16;
}
if (outPNGDepth) {
*outPNGDepth = imgBitDepth;
}
png_read_update_info(png, info);
avif->width = rawWidth;
avif->height = rawHeight;
avif->yuvFormat = requestedFormat;
if (avif->yuvFormat == AVIF_PIXEL_FORMAT_NONE) {
if (avif->matrixCoefficients == AVIF_MATRIX_COEFFICIENTS_IDENTITY) {
// Identity is only valid with YUV444.
avif->yuvFormat = AVIF_PIXEL_FORMAT_YUV444;
} else if ((rawColorType == PNG_COLOR_TYPE_GRAY) || (rawColorType == PNG_COLOR_TYPE_GRAY_ALPHA)) {
avif->yuvFormat = AVIF_PIXEL_FORMAT_YUV400;
} else {
avif->yuvFormat = AVIF_APP_DEFAULT_PIXEL_FORMAT;
}
}
avif->depth = requestedDepth;
if (avif->depth == 0) {
if (imgBitDepth == 8) {
avif->depth = 8;
} else {
avif->depth = 12;
}
}
avifRGBImageSetDefaults(&rgb, avif);
rgb.depth = imgBitDepth;
avifRGBImageAllocatePixels(&rgb);
rowPointers = (png_bytep *)malloc(sizeof(png_bytep) * rgb.height);
for (uint32_t y = 0; y < rgb.height; ++y) {
rowPointers[y] = &rgb.pixels[y * rgb.rowBytes];
}
png_read_image(png, rowPointers);
if (avifImageRGBToYUV(avif, &rgb) != AVIF_RESULT_OK) {
fprintf(stderr, "Conversion to YUV failed: %s\n", inputFilename);
goto cleanup;
}
readResult = AVIF_TRUE;
cleanup:
if (f) {
fclose(f);
}
if (png) {
png_destroy_read_struct(&png, &info, NULL);
}
if (rowPointers) {
free(rowPointers);
}
avifRGBImageFreePixels(&rgb);
return readResult;
}
avifBool avifPNGWrite(const char * outputFilename, const avifImage * avif, uint32_t requestedDepth, avifChromaUpsampling chromaUpsampling, int compressionLevel)
{
volatile avifBool writeResult = AVIF_FALSE;
png_structp png = NULL;
png_infop info = NULL;
png_bytep * volatile rowPointers = NULL;
FILE * volatile f = NULL;
avifRGBImage rgb;
memset(&rgb, 0, sizeof(avifRGBImage));
int rgbDepth = requestedDepth;
if (rgbDepth == 0) {
if (avif->depth > 8) {
rgbDepth = 16;
} else {
rgbDepth = 8;
}
}
avifRGBImageSetDefaults(&rgb, avif);
rgb.depth = rgbDepth;
int colorType = PNG_COLOR_TYPE_RGBA;
if (!avif->alphaPlane) {
colorType = PNG_COLOR_TYPE_RGB;
rgb.format = AVIF_RGB_FORMAT_RGB;
}
rgb.chromaUpsampling = chromaUpsampling;
avifRGBImageAllocatePixels(&rgb);
if (avifImageYUVToRGB(avif, &rgb) != AVIF_RESULT_OK) {
fprintf(stderr, "Conversion to RGB failed: %s\n", outputFilename);
goto cleanup;
}
f = fopen(outputFilename, "wb");
if (!f) {
fprintf(stderr, "Can't open PNG file for write: %s\n", outputFilename);
goto cleanup;
}
png = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
if (!png) {
fprintf(stderr, "Cannot init libpng (png): %s\n", outputFilename);
goto cleanup;
}
info = png_create_info_struct(png);
if (!info) {
fprintf(stderr, "Cannot init libpng (info): %s\n", outputFilename);
goto cleanup;
}
if (setjmp(png_jmpbuf(png))) {
fprintf(stderr, "Error writing PNG: %s\n", outputFilename);
goto cleanup;
}
png_init_io(png, f);
// Don't bother complaining about ICC profile's contents when transferring from AVIF to PNG.
// It is up to the enduser to decide if they want to keep their ICC profiles or not.
#if defined(PNG_SKIP_sRGB_CHECK_PROFILE) && defined(PNG_SET_OPTION_SUPPORTED) // See libpng-manual.txt, section XII.
png_set_option(png, PNG_SKIP_sRGB_CHECK_PROFILE, PNG_OPTION_ON);
#endif
if (compressionLevel >= 0) {
png_set_compression_level(png, compressionLevel);
}
png_set_IHDR(png, info, avif->width, avif->height, rgb.depth, colorType, PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT);
if (avif->icc.data && (avif->icc.size > 0)) {
png_set_iCCP(png, info, "libavif", 0, (png_iccp_datap)avif->icc.data, (png_uint_32)avif->icc.size);
}
png_write_info(png, info);
rowPointers = (png_bytep *)malloc(sizeof(png_bytep) * rgb.height);
for (uint32_t y = 0; y < rgb.height; ++y) {
rowPointers[y] = &rgb.pixels[y * rgb.rowBytes];
}
if (rgb.depth > 8) {
png_set_swap(png);
}
png_write_image(png, rowPointers);
png_write_end(png, NULL);
writeResult = AVIF_TRUE;
printf("Wrote PNG: %s\n", outputFilename);
cleanup:
if (f) {
fclose(f);
}
if (png) {
png_destroy_write_struct(&png, &info);
}
if (rowPointers) {
free(rowPointers);
}
avifRGBImageFreePixels(&rgb);
return writeResult;
}