void
nsPNGDecoder::info_callback(png_structp png_ptr, png_infop info_ptr)
{
// int number_passes; NOT USED
png_uint_32 width, height;
int bit_depth, color_type, interlace_type, compression_type, filter_type;
unsigned int channels;
png_bytep trans = nullptr;
int num_trans = 0;
nsPNGDecoder* decoder =
static_cast<nsPNGDecoder*>(png_get_progressive_ptr(png_ptr));
// Always decode to 24-bit RGB or 32-bit RGBA
png_get_IHDR(png_ptr, info_ptr, &width, &height, &bit_depth, &color_type,
&interlace_type, &compression_type, &filter_type);
// Are we too big?
if (width > MOZ_PNG_MAX_DIMENSION || height > MOZ_PNG_MAX_DIMENSION) {
png_longjmp(decoder->mPNG, 1);
}
// Post our size to the superclass
decoder->PostSize(width, height);
if (decoder->HasError()) {
// Setting the size led to an error.
png_longjmp(decoder->mPNG, 1);
}
if (color_type == PNG_COLOR_TYPE_PALETTE) {
png_set_expand(png_ptr);
}
if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8) {
png_set_expand(png_ptr);
}
if (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS)) {
png_color_16p trans_values;
png_get_tRNS(png_ptr, info_ptr, &trans, &num_trans, &trans_values);
// libpng doesn't reject a tRNS chunk with out-of-range samples
// so we check it here to avoid setting up a useless opacity
// channel or producing unexpected transparent pixels (bug #428045)
if (bit_depth < 16) {
png_uint_16 sample_max = (1 << bit_depth) - 1;
if ((color_type == PNG_COLOR_TYPE_GRAY &&
trans_values->gray > sample_max) ||
(color_type == PNG_COLOR_TYPE_RGB &&
(trans_values->red > sample_max ||
trans_values->green > sample_max ||
trans_values->blue > sample_max))) {
// clear the tRNS valid flag and release tRNS memory
png_free_data(png_ptr, info_ptr, PNG_FREE_TRNS, 0);
num_trans = 0;
}
}
if (num_trans != 0) {
png_set_expand(png_ptr);
}
}
if (bit_depth == 16) {
png_set_scale_16(png_ptr);
}
qcms_data_type inType = QCMS_DATA_RGBA_8;
uint32_t intent = -1;
uint32_t pIntent;
if (decoder->mCMSMode != eCMSMode_Off) {
intent = gfxPlatform::GetRenderingIntent();
decoder->mInProfile = PNGGetColorProfile(png_ptr, info_ptr,
color_type, &inType, &pIntent);
// If we're not mandating an intent, use the one from the image.
if (intent == uint32_t(-1)) {
intent = pIntent;
}
}
if (decoder->mInProfile && gfxPlatform::GetCMSOutputProfile()) {
qcms_data_type outType;
if (color_type & PNG_COLOR_MASK_ALPHA || num_trans) {
outType = QCMS_DATA_RGBA_8;
} else {
outType = QCMS_DATA_RGB_8;
}
decoder->mTransform = qcms_transform_create(decoder->mInProfile,
inType,
gfxPlatform::GetCMSOutputProfile(),
outType,
(qcms_intent)intent);
} else {
png_set_gray_to_rgb(png_ptr);
// only do gamma correction if CMS isn't entirely disabled
if (decoder->mCMSMode != eCMSMode_Off) {
PNGDoGammaCorrection(png_ptr, info_ptr);
}
if (decoder->mCMSMode == eCMSMode_All) {
if (color_type & PNG_COLOR_MASK_ALPHA || num_trans) {
decoder->mTransform = gfxPlatform::GetCMSRGBATransform();
} else {
decoder->mTransform = gfxPlatform::GetCMSRGBTransform();
}
}
}
// let libpng expand interlaced images
if (interlace_type == PNG_INTERLACE_ADAM7) {
// number_passes =
png_set_interlace_handling(png_ptr);
}
// now all of those things we set above are used to update various struct
// members and whatnot, after which we can get channels, rowbytes, etc.
png_read_update_info(png_ptr, info_ptr);
decoder->mChannels = channels = png_get_channels(png_ptr, info_ptr);
//---------------------------------------------------------------//
// copy PNG info into imagelib structs (formerly png_set_dims()) //
//---------------------------------------------------------------//
if (channels == 1 || channels == 3) {
decoder->format = gfx::SurfaceFormat::B8G8R8X8;
} else if (channels == 2 || channels == 4) {
decoder->format = gfx::SurfaceFormat::B8G8R8A8;
} else {
png_longjmp(decoder->mPNG, 1); // invalid number of channels
}
#ifdef PNG_APNG_SUPPORTED
if (png_get_valid(png_ptr, info_ptr, PNG_INFO_acTL)) {
png_set_progressive_frame_fn(png_ptr, nsPNGDecoder::frame_info_callback,
nullptr);
}
if (png_get_first_frame_is_hidden(png_ptr, info_ptr)) {
decoder->mFrameIsHidden = true;
} else {
#endif
decoder->CreateFrame(0, 0, width, height, decoder->format);
#ifdef PNG_APNG_SUPPORTED
}
#endif
if (decoder->mTransform &&
(channels <= 2 || interlace_type == PNG_INTERLACE_ADAM7)) {
uint32_t bpp[] = { 0, 3, 4, 3, 4 };
decoder->mCMSLine =
(uint8_t*)malloc(bpp[channels] * width);
if (!decoder->mCMSLine) {
png_longjmp(decoder->mPNG, 5); // NS_ERROR_OUT_OF_MEMORY
}
}
if (interlace_type == PNG_INTERLACE_ADAM7) {
if (height < INT32_MAX / (width * channels)) {
decoder->interlacebuf = (uint8_t*)malloc(channels * width * height);
}
if (!decoder->interlacebuf) {
png_longjmp(decoder->mPNG, 5); // NS_ERROR_OUT_OF_MEMORY
}
}
if (decoder->NeedsNewFrame()) {
// We know that we need a new frame, so pause input so the decoder
// infrastructure can give it to us.
png_process_data_pause(png_ptr, /* save = */ 1);
}
}
void
nsPNGDecoder::info_callback(png_structp png_ptr, png_infop info_ptr)
{
/* int number_passes; NOT USED */
png_uint_32 width, height;
int bit_depth, color_type, interlace_type, compression_type, filter_type;
unsigned int channels;
png_bytep trans = NULL;
int num_trans = 0;
nsPNGDecoder *decoder =
static_cast<nsPNGDecoder*>(png_get_progressive_ptr(png_ptr));
/* always decode to 24-bit RGB or 32-bit RGBA */
png_get_IHDR(png_ptr, info_ptr, &width, &height, &bit_depth, &color_type,
&interlace_type, &compression_type, &filter_type);
/* Are we too big? */
if (width > MOZ_PNG_MAX_DIMENSION || height > MOZ_PNG_MAX_DIMENSION)
longjmp(png_jmpbuf(decoder->mPNG), 1);
// Post our size to the superclass
decoder->PostSize(width, height);
if (decoder->HasError()) {
// Setting the size lead to an error; this can happen when for example
// a multipart channel sends an image of a different size.
longjmp(png_jmpbuf(decoder->mPNG), 1);
}
if (color_type == PNG_COLOR_TYPE_PALETTE)
png_set_expand(png_ptr);
if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8)
png_set_expand(png_ptr);
if (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS)) {
int sample_max = (1 << bit_depth);
png_color_16p trans_values;
png_get_tRNS(png_ptr, info_ptr, &trans, &num_trans, &trans_values);
/* libpng doesn't reject a tRNS chunk with out-of-range samples
so we check it here to avoid setting up a useless opacity
channel or producing unexpected transparent pixels when using
libpng-1.2.19 through 1.2.26 (bug #428045) */
if ((color_type == PNG_COLOR_TYPE_GRAY &&
(int)trans_values->gray > sample_max) ||
(color_type == PNG_COLOR_TYPE_RGB &&
((int)trans_values->red > sample_max ||
(int)trans_values->green > sample_max ||
(int)trans_values->blue > sample_max)))
{
/* clear the tRNS valid flag and release tRNS memory */
png_free_data(png_ptr, info_ptr, PNG_FREE_TRNS, 0);
}
else
png_set_expand(png_ptr);
}
if (bit_depth == 16)
png_set_strip_16(png_ptr);
qcms_data_type inType;
PRUint32 intent = -1;
PRUint32 pIntent;
if (decoder->mCMSMode != eCMSMode_Off) {
intent = gfxPlatform::GetRenderingIntent();
decoder->mInProfile = PNGGetColorProfile(png_ptr, info_ptr,
color_type, &inType, &pIntent);
/* If we're not mandating an intent, use the one from the image. */
if (intent == PRUint32(-1))
intent = pIntent;
}
if (decoder->mInProfile && gfxPlatform::GetCMSOutputProfile()) {
qcms_data_type outType;
if (color_type & PNG_COLOR_MASK_ALPHA || num_trans)
outType = QCMS_DATA_RGBA_8;
else
outType = QCMS_DATA_RGB_8;
decoder->mTransform = qcms_transform_create(decoder->mInProfile,
inType,
gfxPlatform::GetCMSOutputProfile(),
outType,
(qcms_intent)intent);
} else {
png_set_gray_to_rgb(png_ptr);
// only do gamma correction if CMS isn't entirely disabled
if (decoder->mCMSMode != eCMSMode_Off)
PNGDoGammaCorrection(png_ptr, info_ptr);
if (decoder->mCMSMode == eCMSMode_All) {
if (color_type & PNG_COLOR_MASK_ALPHA || num_trans)
decoder->mTransform = gfxPlatform::GetCMSRGBATransform();
else
decoder->mTransform = gfxPlatform::GetCMSRGBTransform();
}
}
/* let libpng expand interlaced images */
if (interlace_type == PNG_INTERLACE_ADAM7) {
/* number_passes = */
png_set_interlace_handling(png_ptr);
}
/* now all of those things we set above are used to update various struct
* members and whatnot, after which we can get channels, rowbytes, etc. */
png_read_update_info(png_ptr, info_ptr);
decoder->mChannels = channels = png_get_channels(png_ptr, info_ptr);
/*---------------------------------------------------------------*/
/* copy PNG info into imagelib structs (formerly png_set_dims()) */
/*---------------------------------------------------------------*/
PRInt32 alpha_bits = 1;
if (channels == 2 || channels == 4) {
/* check if alpha is coming from a tRNS chunk and is binary */
if (num_trans) {
/* if it's not an indexed color image, tRNS means binary */
if (color_type == PNG_COLOR_TYPE_PALETTE) {
for (int i=0; i<num_trans; i++) {
if ((trans[i] != 0) && (trans[i] != 255)) {
alpha_bits = 8;
break;
}
}
}
} else {
alpha_bits = 8;
}
}
if (channels == 1 || channels == 3)
decoder->format = gfxASurface::ImageFormatRGB24;
else if (channels == 2 || channels == 4)
decoder->format = gfxASurface::ImageFormatARGB32;
#ifdef PNG_APNG_SUPPORTED
if (png_get_valid(png_ptr, info_ptr, PNG_INFO_acTL))
png_set_progressive_frame_fn(png_ptr, nsPNGDecoder::frame_info_callback, NULL);
if (png_get_first_frame_is_hidden(png_ptr, info_ptr)) {
decoder->mFrameIsHidden = PR_TRUE;
} else {
#endif
decoder->CreateFrame(0, 0, width, height, decoder->format);
#ifdef PNG_APNG_SUPPORTED
}
#endif
if (decoder->mTransform &&
(channels <= 2 || interlace_type == PNG_INTERLACE_ADAM7)) {
PRUint32 bpp[] = { 0, 3, 4, 3, 4 };
decoder->mCMSLine =
(PRUint8 *)moz_malloc(bpp[channels] * width);
if (!decoder->mCMSLine) {
longjmp(png_jmpbuf(decoder->mPNG), 5); // NS_ERROR_OUT_OF_MEMORY
}
}
if (interlace_type == PNG_INTERLACE_ADAM7) {
if (height < PR_INT32_MAX / (width * channels))
decoder->interlacebuf = (PRUint8 *)moz_malloc(channels * width * height);
if (!decoder->interlacebuf) {
longjmp(png_jmpbuf(decoder->mPNG), 5); // NS_ERROR_OUT_OF_MEMORY
}
}
/* Reject any ancillary chunk after IDAT with a bad CRC (bug #397593).
* It would be better to show the default frame (if one has already been
* successfully decoded) before bailing, but it's simpler to just bail
* out with an error message.
*/
png_set_crc_action(png_ptr, PNG_CRC_NO_CHANGE, PNG_CRC_ERROR_QUIT);
return;
}
