pjs/image/decoders/nsPNGDecoder.cpp

892 строки
28 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
*
* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is mozilla.org code.
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 2001
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Stuart Parmenter <stuart@mozilla.com>
* Andrew Smith
* Federico Mena-Quintero <federico@novell.com>
* Bobby Holley <bobbyholley@gmail.com>
* Glenn Randers-Pehrson <glennrp@gmail.com>
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#include "nsPNGDecoder.h"
#include "ImageLogging.h"
#include "nsMemory.h"
#include "nsRect.h"
#include "nsIInputStream.h"
#include "RasterImage.h"
#include "imgIContainerObserver.h"
#include "gfxColor.h"
#include "nsColor.h"
#include "nspr.h"
#include "png.h"
#include "gfxPlatform.h"
namespace mozilla {
namespace image {
#ifdef PR_LOGGING
static PRLogModuleInfo *gPNGLog = PR_NewLogModule("PNGDecoder");
static PRLogModuleInfo *gPNGDecoderAccountingLog =
PR_NewLogModule("PNGDecoderAccounting");
#endif
/* limit image dimensions (bug #251381) */
#define MOZ_PNG_MAX_DIMENSION 1000000L
// For size decodes
#define WIDTH_OFFSET 16
#define HEIGHT_OFFSET (WIDTH_OFFSET + 4)
#define BYTES_NEEDED_FOR_DIMENSIONS (HEIGHT_OFFSET + 4)
// First 8 bytes of a PNG file
const PRUint8
nsPNGDecoder::pngSignatureBytes[] = { 137, 80, 78, 71, 13, 10, 26, 10 };
nsPNGDecoder::nsPNGDecoder(RasterImage &aImage, imgIDecoderObserver* aObserver)
: Decoder(aImage, aObserver),
mPNG(nsnull), mInfo(nsnull),
mCMSLine(nsnull), interlacebuf(nsnull),
mInProfile(nsnull), mTransform(nsnull),
mHeaderBuf(nsnull), mHeaderBytesRead(0),
mChannels(0), mFrameIsHidden(false),
mCMSMode(0), mDisablePremultipliedAlpha(false)
{
}
nsPNGDecoder::~nsPNGDecoder()
{
if (mPNG)
png_destroy_read_struct(&mPNG, mInfo ? &mInfo : NULL, NULL);
if (mCMSLine)
nsMemory::Free(mCMSLine);
if (interlacebuf)
nsMemory::Free(interlacebuf);
if (mInProfile) {
qcms_profile_release(mInProfile);
/* mTransform belongs to us only if mInProfile is non-null */
if (mTransform)
qcms_transform_release(mTransform);
}
if (mHeaderBuf)
nsMemory::Free(mHeaderBuf);
}
// CreateFrame() is used for both simple and animated images
void nsPNGDecoder::CreateFrame(png_uint_32 x_offset, png_uint_32 y_offset,
PRInt32 width, PRInt32 height,
gfxASurface::gfxImageFormat format)
{
PRUint32 imageDataLength;
nsresult rv = mImage.EnsureFrame(GetFrameCount(), x_offset, y_offset,
width, height, format,
&mImageData, &imageDataLength);
if (NS_FAILED(rv))
longjmp(png_jmpbuf(mPNG), 5); // NS_ERROR_OUT_OF_MEMORY
mFrameRect.x = x_offset;
mFrameRect.y = y_offset;
mFrameRect.width = width;
mFrameRect.height = height;
#ifdef PNG_APNG_SUPPORTED
if (png_get_valid(mPNG, mInfo, PNG_INFO_acTL))
SetAnimFrameInfo();
#endif
// Tell the superclass we're starting a frame
PostFrameStart();
PR_LOG(gPNGDecoderAccountingLog, PR_LOG_DEBUG,
("PNGDecoderAccounting: nsPNGDecoder::CreateFrame -- created "
"image frame with %dx%d pixels in container %p",
width, height,
&mImage));
mFrameHasNoAlpha = true;
}
#ifdef PNG_APNG_SUPPORTED
// set timeout and frame disposal method for the current frame
void nsPNGDecoder::SetAnimFrameInfo()
{
png_uint_16 delay_num, delay_den;
/* delay, in seconds is delay_num/delay_den */
png_byte dispose_op;
png_byte blend_op;
PRInt32 timeout; /* in milliseconds */
delay_num = png_get_next_frame_delay_num(mPNG, mInfo);
delay_den = png_get_next_frame_delay_den(mPNG, mInfo);
dispose_op = png_get_next_frame_dispose_op(mPNG, mInfo);
blend_op = png_get_next_frame_blend_op(mPNG, mInfo);
if (delay_num == 0) {
timeout = 0; // SetFrameTimeout() will set to a minimum
} else {
if (delay_den == 0)
delay_den = 100; // so says the APNG spec
// Need to cast delay_num to float to have a proper division and
// the result to int to avoid compiler warning
timeout = static_cast<PRInt32>
(static_cast<PRFloat64>(delay_num) * 1000 / delay_den);
}
PRUint32 numFrames = mImage.GetNumFrames();
mImage.SetFrameTimeout(numFrames - 1, timeout);
if (dispose_op == PNG_DISPOSE_OP_PREVIOUS)
mImage.SetFrameDisposalMethod(numFrames - 1,
RasterImage::kDisposeRestorePrevious);
else if (dispose_op == PNG_DISPOSE_OP_BACKGROUND)
mImage.SetFrameDisposalMethod(numFrames - 1,
RasterImage::kDisposeClear);
else
mImage.SetFrameDisposalMethod(numFrames - 1,
RasterImage::kDisposeKeep);
if (blend_op == PNG_BLEND_OP_SOURCE)
mImage.SetFrameBlendMethod(numFrames - 1, RasterImage::kBlendSource);
/*else // 'over' is the default
mImage.SetFrameBlendMethod(numFrames - 1, RasterImage::kBlendOver); */
}
#endif
// set timeout and frame disposal method for the current frame
void nsPNGDecoder::EndImageFrame()
{
if (mFrameIsHidden)
return;
PRUint32 numFrames = 1;
#ifdef PNG_APNG_SUPPORTED
numFrames = mImage.GetNumFrames();
// We can't use mPNG->num_frames_read as it may be one ahead.
if (numFrames > 1) {
// Tell the image renderer that the frame is complete
if (mFrameHasNoAlpha)
mImage.SetFrameHasNoAlpha(numFrames - 1);
PostInvalidation(mFrameRect);
}
#endif
PostFrameStop();
}
void
nsPNGDecoder::InitInternal()
{
mCMSMode = gfxPlatform::GetCMSMode();
if ((mDecodeFlags & DECODER_NO_COLORSPACE_CONVERSION) != 0)
mCMSMode = eCMSMode_Off;
mDisablePremultipliedAlpha = (mDecodeFlags & DECODER_NO_PREMULTIPLY_ALPHA) != 0;
#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
static png_byte color_chunks[]=
{ 99, 72, 82, 77, '\0', /* cHRM */
105, 67, 67, 80, '\0'}; /* iCCP */
static png_byte unused_chunks[]=
{ 98, 75, 71, 68, '\0', /* bKGD */
104, 73, 83, 84, '\0', /* hIST */
105, 84, 88, 116, '\0', /* iTXt */
111, 70, 70, 115, '\0', /* oFFs */
112, 67, 65, 76, '\0', /* pCAL */
115, 67, 65, 76, '\0', /* sCAL */
112, 72, 89, 115, '\0', /* pHYs */
115, 66, 73, 84, '\0', /* sBIT */
115, 80, 76, 84, '\0', /* sPLT */
116, 69, 88, 116, '\0', /* tEXt */
116, 73, 77, 69, '\0', /* tIME */
122, 84, 88, 116, '\0'}; /* zTXt */
#endif
// For size decodes, we only need a small buffer
if (IsSizeDecode()) {
mHeaderBuf = (PRUint8 *)moz_xmalloc(BYTES_NEEDED_FOR_DIMENSIONS);
return;
}
/* For full decodes, do png init stuff */
/* Initialize the container's source image header. */
/* Always decode to 24 bit pixdepth */
mPNG = png_create_read_struct(PNG_LIBPNG_VER_STRING,
NULL, nsPNGDecoder::error_callback,
nsPNGDecoder::warning_callback);
if (!mPNG) {
PostDecoderError(NS_ERROR_OUT_OF_MEMORY);
return;
}
mInfo = png_create_info_struct(mPNG);
if (!mInfo) {
PostDecoderError(NS_ERROR_OUT_OF_MEMORY);
png_destroy_read_struct(&mPNG, NULL, NULL);
return;
}
#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
/* Ignore unused chunks */
if (mCMSMode == eCMSMode_Off)
png_set_keep_unknown_chunks(mPNG, 1, color_chunks, 2);
png_set_keep_unknown_chunks(mPNG, 1, unused_chunks,
(int)sizeof(unused_chunks)/5);
#endif
#ifdef PNG_SET_CHUNK_MALLOC_LIMIT_SUPPORTED
if (mCMSMode != eCMSMode_Off)
png_set_chunk_malloc_max(mPNG, 4000000L);
#endif
/* use this as libpng "progressive pointer" (retrieve in callbacks) */
png_set_progressive_read_fn(mPNG, static_cast<png_voidp>(this),
nsPNGDecoder::info_callback,
nsPNGDecoder::row_callback,
nsPNGDecoder::end_callback);
}
void
nsPNGDecoder::WriteInternal(const char *aBuffer, PRUint32 aCount)
{
// We use gotos, so we need to declare variables here
PRUint32 width = 0;
PRUint32 height = 0;
NS_ABORT_IF_FALSE(!HasError(), "Shouldn't call WriteInternal after error!");
// If we only want width/height, we don't need to go through libpng
if (IsSizeDecode()) {
// Are we done?
if (mHeaderBytesRead == BYTES_NEEDED_FOR_DIMENSIONS)
return;
// Read data into our header buffer
PRUint32 bytesToRead = NS_MIN(aCount, BYTES_NEEDED_FOR_DIMENSIONS -
mHeaderBytesRead);
memcpy(mHeaderBuf + mHeaderBytesRead, aBuffer, bytesToRead);
mHeaderBytesRead += bytesToRead;
// If we're done now, verify the data and set up the container
if (mHeaderBytesRead == BYTES_NEEDED_FOR_DIMENSIONS) {
// Check that the signature bytes are right
if (memcmp(mHeaderBuf, nsPNGDecoder::pngSignatureBytes,
sizeof(pngSignatureBytes))) {
PostDataError();
return;
}
// Grab the width and height, accounting for endianness (thanks libpng!)
width = png_get_uint_32(mHeaderBuf + WIDTH_OFFSET);
height = png_get_uint_32(mHeaderBuf + HEIGHT_OFFSET);
// Too big?
if ((width > MOZ_PNG_MAX_DIMENSION) || (height > MOZ_PNG_MAX_DIMENSION)) {
PostDataError();
return;
}
// Post our size to the superclass
PostSize(width, height);
}
}
// Otherwise, we're doing a standard decode
else {
// libpng uses setjmp/longjmp for error handling - set the buffer
if (setjmp(png_jmpbuf(mPNG))) {
// We might not really know what caused the error, but it makes more
// sense to blame the data.
if (!HasError())
PostDataError();
png_destroy_read_struct(&mPNG, &mInfo, NULL);
return;
}
// Pass the data off to libpng
png_process_data(mPNG, mInfo, (unsigned char *)aBuffer, aCount);
}
}
// Sets up gamma pre-correction in libpng before our callback gets called.
// We need to do this if we don't end up with a CMS profile.
static void
PNGDoGammaCorrection(png_structp png_ptr, png_infop info_ptr)
{
double aGamma;
if (png_get_gAMA(png_ptr, info_ptr, &aGamma)) {
if ((aGamma <= 0.0) || (aGamma > 21474.83)) {
aGamma = 0.45455;
png_set_gAMA(png_ptr, info_ptr, aGamma);
}
png_set_gamma(png_ptr, 2.2, aGamma);
}
else
png_set_gamma(png_ptr, 2.2, 0.45455);
}
// Adapted from http://www.littlecms.com/pngchrm.c example code
static qcms_profile *
PNGGetColorProfile(png_structp png_ptr, png_infop info_ptr,
int color_type, qcms_data_type *inType, PRUint32 *intent)
{
qcms_profile *profile = nsnull;
*intent = QCMS_INTENT_PERCEPTUAL; // Our default
// First try to see if iCCP chunk is present
if (png_get_valid(png_ptr, info_ptr, PNG_INFO_iCCP)) {
png_uint_32 profileLen;
#if (PNG_LIBPNG_VER < 10500)
char *profileData, *profileName;
#else
png_bytep profileData;
png_charp profileName;
#endif
int compression;
png_get_iCCP(png_ptr, info_ptr, &profileName, &compression,
&profileData, &profileLen);
profile = qcms_profile_from_memory(
#if (PNG_LIBPNG_VER < 10500)
profileData,
#else
(char *)profileData,
#endif
profileLen);
if (profile) {
PRUint32 profileSpace = qcms_profile_get_color_space(profile);
bool mismatch = false;
if (color_type & PNG_COLOR_MASK_COLOR) {
if (profileSpace != icSigRgbData)
mismatch = true;
} else {
if (profileSpace == icSigRgbData)
png_set_gray_to_rgb(png_ptr);
else if (profileSpace != icSigGrayData)
mismatch = true;
}
if (mismatch) {
qcms_profile_release(profile);
profile = nsnull;
} else {
*intent = qcms_profile_get_rendering_intent(profile);
}
}
}
// Check sRGB chunk
if (!profile && png_get_valid(png_ptr, info_ptr, PNG_INFO_sRGB)) {
profile = qcms_profile_sRGB();
if (profile) {
int fileIntent;
png_set_gray_to_rgb(png_ptr);
png_get_sRGB(png_ptr, info_ptr, &fileIntent);
PRUint32 map[] = { QCMS_INTENT_PERCEPTUAL,
QCMS_INTENT_RELATIVE_COLORIMETRIC,
QCMS_INTENT_SATURATION,
QCMS_INTENT_ABSOLUTE_COLORIMETRIC };
*intent = map[fileIntent];
}
}
// Check gAMA/cHRM chunks
if (!profile &&
png_get_valid(png_ptr, info_ptr, PNG_INFO_gAMA) &&
png_get_valid(png_ptr, info_ptr, PNG_INFO_cHRM)) {
qcms_CIE_xyYTRIPLE primaries;
qcms_CIE_xyY whitePoint;
png_get_cHRM(png_ptr, info_ptr,
&whitePoint.x, &whitePoint.y,
&primaries.red.x, &primaries.red.y,
&primaries.green.x, &primaries.green.y,
&primaries.blue.x, &primaries.blue.y);
whitePoint.Y =
primaries.red.Y = primaries.green.Y = primaries.blue.Y = 1.0;
double gammaOfFile;
png_get_gAMA(png_ptr, info_ptr, &gammaOfFile);
profile = qcms_profile_create_rgb_with_gamma(whitePoint, primaries,
1.0/gammaOfFile);
if (profile)
png_set_gray_to_rgb(png_ptr);
}
if (profile) {
PRUint32 profileSpace = qcms_profile_get_color_space(profile);
if (profileSpace == icSigGrayData) {
if (color_type & PNG_COLOR_MASK_ALPHA)
*inType = QCMS_DATA_GRAYA_8;
else
*inType = QCMS_DATA_GRAY_8;
} else {
if (color_type & PNG_COLOR_MASK_ALPHA ||
png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS))
*inType = QCMS_DATA_RGBA_8;
else
*inType = QCMS_DATA_RGB_8;
}
}
return profile;
}
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_scale_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 = 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;
}
void
nsPNGDecoder::row_callback(png_structp png_ptr, png_bytep new_row,
png_uint_32 row_num, int pass)
{
/* libpng comments:
*
* this function is called for every row in the image. If the
* image is interlacing, and you turned on the interlace handler,
* this function will be called for every row in every pass.
* Some of these rows will not be changed from the previous pass.
* When the row is not changed, the new_row variable will be NULL.
* The rows and passes are called in order, so you don't really
* need the row_num and pass, but I'm supplying them because it
* may make your life easier.
*
* For the non-NULL rows of interlaced images, you must call
* png_progressive_combine_row() passing in the row and the
* old row. You can call this function for NULL rows (it will
* just return) and for non-interlaced images (it just does the
* memcpy for you) if it will make the code easier. Thus, you
* can just do this for all cases:
*
* png_progressive_combine_row(png_ptr, old_row, new_row);
*
* where old_row is what was displayed for previous rows. Note
* that the first pass (pass == 0 really) will completely cover
* the old row, so the rows do not have to be initialized. After
* the first pass (and only for interlaced images), you will have
* to pass the current row, and the function will combine the
* old row and the new row.
*/
nsPNGDecoder *decoder =
static_cast<nsPNGDecoder*>(png_get_progressive_ptr(png_ptr));
// skip this frame
if (decoder->mFrameIsHidden)
return;
if (row_num >= (png_uint_32) decoder->mFrameRect.height)
return;
if (new_row) {
PRInt32 width = decoder->mFrameRect.width;
PRUint32 iwidth = decoder->mFrameRect.width;
png_bytep line = new_row;
if (decoder->interlacebuf) {
line = decoder->interlacebuf + (row_num * decoder->mChannels * width);
png_progressive_combine_row(png_ptr, line, new_row);
}
PRUint32 bpr = width * sizeof(PRUint32);
PRUint32 *cptr32 = (PRUint32*)(decoder->mImageData + (row_num*bpr));
bool rowHasNoAlpha = true;
if (decoder->mTransform) {
if (decoder->mCMSLine) {
qcms_transform_data(decoder->mTransform, line, decoder->mCMSLine,
iwidth);
/* copy alpha over */
PRUint32 channels = decoder->mChannels;
if (channels == 2 || channels == 4) {
for (PRUint32 i = 0; i < iwidth; i++)
decoder->mCMSLine[4 * i + 3] = line[channels * i + channels - 1];
}
line = decoder->mCMSLine;
} else {
qcms_transform_data(decoder->mTransform, line, line, iwidth);
}
}
switch (decoder->format) {
case gfxASurface::ImageFormatRGB24:
{
// counter for while() loops below
PRUint32 idx = iwidth;
// copy as bytes until source pointer is 32-bit-aligned
for (; (NS_PTR_TO_UINT32(line) & 0x3) && idx; --idx) {
*cptr32++ = GFX_PACKED_PIXEL(0xFF, line[0], line[1], line[2]);
line += 3;
}
// copy pixels in blocks of 4
while (idx >= 4) {
GFX_BLOCK_RGB_TO_FRGB(line, cptr32);
idx -= 4;
line += 12;
cptr32 += 4;
}
// copy remaining pixel(s)
while (idx--) {
// 32-bit read of final pixel will exceed buffer, so read bytes
*cptr32++ = GFX_PACKED_PIXEL(0xFF, line[0], line[1], line[2]);
line += 3;
}
}
break;
case gfxASurface::ImageFormatARGB32:
{
if (!decoder->mDisablePremultipliedAlpha) {
for (PRUint32 x=width; x>0; --x) {
*cptr32++ = GFX_PACKED_PIXEL(line[3], line[0], line[1], line[2]);
if (line[3] != 0xff)
rowHasNoAlpha = false;
line += 4;
}
} else {
for (PRUint32 x=width; x>0; --x) {
*cptr32++ = GFX_PACKED_PIXEL_NO_PREMULTIPLY(line[3], line[0], line[1], line[2]);
if (line[3] != 0xff)
rowHasNoAlpha = false;
line += 4;
}
}
}
break;
default:
longjmp(png_jmpbuf(decoder->mPNG), 1);
}
if (!rowHasNoAlpha)
decoder->mFrameHasNoAlpha = false;
PRUint32 numFrames = decoder->mImage.GetNumFrames();
if (numFrames <= 1) {
// Only do incremental image display for the first frame
// XXXbholley - this check should be handled in the superclass
nsIntRect r(0, row_num, width, 1);
decoder->PostInvalidation(r);
}
}
}
// got the header of a new frame that's coming
void
nsPNGDecoder::frame_info_callback(png_structp png_ptr, png_uint_32 frame_num)
{
#ifdef PNG_APNG_SUPPORTED
png_uint_32 x_offset, y_offset;
PRInt32 width, height;
nsPNGDecoder *decoder =
static_cast<nsPNGDecoder*>(png_get_progressive_ptr(png_ptr));
// old frame is done
decoder->EndImageFrame();
// Only the first frame can be hidden, so unhide unconditionally here.
decoder->mFrameIsHidden = false;
x_offset = png_get_next_frame_x_offset(png_ptr, decoder->mInfo);
y_offset = png_get_next_frame_y_offset(png_ptr, decoder->mInfo);
width = png_get_next_frame_width(png_ptr, decoder->mInfo);
height = png_get_next_frame_height(png_ptr, decoder->mInfo);
decoder->CreateFrame(x_offset, y_offset, width, height, decoder->format);
#endif
}
void
nsPNGDecoder::end_callback(png_structp png_ptr, png_infop info_ptr)
{
/* libpng comments:
*
* this function is called when the whole image has been read,
* including any chunks after the image (up to and including
* the IEND). You will usually have the same info chunk as you
* had in the header, although some data may have been added
* to the comments and time fields.
*
* Most people won't do much here, perhaps setting a flag that
* marks the image as finished.
*/
nsPNGDecoder *decoder =
static_cast<nsPNGDecoder*>(png_get_progressive_ptr(png_ptr));
// We shouldn't get here if we've hit an error
NS_ABORT_IF_FALSE(!decoder->HasError(), "Finishing up PNG but hit error!");
#ifdef PNG_APNG_SUPPORTED
if (png_get_valid(png_ptr, info_ptr, PNG_INFO_acTL)) {
PRInt32 num_plays = png_get_num_plays(png_ptr, info_ptr);
decoder->mImage.SetLoopCount(num_plays - 1);
}
#endif
// Send final notifications
decoder->EndImageFrame();
decoder->PostDecodeDone();
}
void
nsPNGDecoder::error_callback(png_structp png_ptr, png_const_charp error_msg)
{
PR_LOG(gPNGLog, PR_LOG_ERROR, ("libpng error: %s\n", error_msg));
longjmp(png_jmpbuf(png_ptr), 1);
}
void
nsPNGDecoder::warning_callback(png_structp png_ptr, png_const_charp warning_msg)
{
PR_LOG(gPNGLog, PR_LOG_WARNING, ("libpng warning: %s\n", warning_msg));
}
Telemetry::ID
nsPNGDecoder::SpeedHistogram()
{
return Telemetry::IMAGE_DECODE_SPEED_PNG;
}
} // namespace image
} // namespace mozilla