| /* |
| * Copyright (C) 2006 Apple Inc. |
| * Copyright (C) 2007-2009 Torch Mobile, Inc. |
| * Copyright (C) Research In Motion Limited 2009-2010. All rights reserved. |
| * |
| * Portions are Copyright (C) 2001 mozilla.org |
| * |
| * Other contributors: |
| * Stuart Parmenter <stuart@mozilla.com> |
| * Max Stepin <maxstepin@gmail.com> |
| * |
| * This library is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU Lesser General Public |
| * License as published by the Free Software Foundation; either |
| * version 2.1 of the License, or (at your option) any later version. |
| * |
| * This library is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * Lesser General Public License for more details. |
| * |
| * You should have received a copy of the GNU Lesser General Public |
| * License along with this library; if not, write to the Free Software |
| * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| * |
| * Alternatively, the contents of this file may be used under the terms |
| * of either the Mozilla Public License Version 1.1, found at |
| * http://www.mozilla.org/MPL/ (the "MPL") or the GNU General Public |
| * License Version 2.0, found at http://www.fsf.org/copyleft/gpl.html |
| * (the "GPL"), in which case the provisions of the MPL or the GPL are |
| * applicable instead of those above. If you wish to allow use of your |
| * version of this file only under the terms of one of those two |
| * licenses (the MPL or the GPL) and not to allow others to use your |
| * version of this file under the LGPL, indicate your decision by |
| * deletingthe provisions above and replace them with the notice and |
| * other provisions required by the MPL or the GPL, as the case may be. |
| * If you do not delete the provisions above, a recipient may use your |
| * version of this file under any of the LGPL, the MPL or the GPL. |
| */ |
| |
| #include "config.h" |
| #include "PNGImageDecoder.h" |
| |
| #include "Color.h" |
| #include <png.h> |
| #include <wtf/StdLibExtras.h> |
| #include <wtf/UniqueArray.h> |
| |
| #if defined(PNG_LIBPNG_VER_MAJOR) && defined(PNG_LIBPNG_VER_MINOR) && (PNG_LIBPNG_VER_MAJOR > 1 || (PNG_LIBPNG_VER_MAJOR == 1 && PNG_LIBPNG_VER_MINOR >= 4)) |
| #define JMPBUF(png_ptr) png_jmpbuf(png_ptr) |
| #else |
| #define JMPBUF(png_ptr) png_ptr->jmpbuf |
| #endif |
| |
| namespace WebCore { |
| |
| // Gamma constants. |
| const double cMaxGamma = 21474.83; |
| const double cDefaultGamma = 2.2; |
| const double cInverseGamma = 0.45455; |
| |
| // Protect against large PNGs. See Mozilla's bug #251381 for more info. |
| const unsigned long cMaxPNGSize = 1000000UL; |
| |
| // Called if the decoding of the image fails. |
| static void PNGAPI decodingFailed(png_structp png, png_const_charp) |
| { |
| longjmp(JMPBUF(png), 1); |
| } |
| |
| // Callbacks given to the read struct. The first is for warnings (we want to |
| // treat a particular warning as an error, which is why we have to register this |
| // callback). |
| static void PNGAPI decodingWarning(png_structp png, png_const_charp warningMsg) |
| { |
| // Mozilla did this, so we will too. |
| // Convert a tRNS warning to be an error (see |
| // http://bugzilla.mozilla.org/show_bug.cgi?id=251381 ) |
| if (!strncmp(warningMsg, "Missing PLTE before tRNS", 24)) |
| png_error(png, warningMsg); |
| } |
| |
| // Called when we have obtained the header information (including the size). |
| static void PNGAPI headerAvailable(png_structp png, png_infop) |
| { |
| static_cast<PNGImageDecoder*>(png_get_progressive_ptr(png))->headerAvailable(); |
| } |
| |
| // Called when a row is ready. |
| static void PNGAPI rowAvailable(png_structp png, png_bytep rowBuffer, png_uint_32 rowIndex, int interlacePass) |
| { |
| static_cast<PNGImageDecoder*>(png_get_progressive_ptr(png))->rowAvailable(rowBuffer, rowIndex, interlacePass); |
| } |
| |
| // Called when we have completely finished decoding the image. |
| static void PNGAPI pngComplete(png_structp png, png_infop) |
| { |
| static_cast<PNGImageDecoder*>(png_get_progressive_ptr(png))->pngComplete(); |
| } |
| |
| #if ENABLE(APNG) |
| // Called when we have the frame header. |
| static void PNGAPI frameHeader(png_structp png, png_infop) |
| { |
| static_cast<PNGImageDecoder*>(png_get_progressive_ptr(png))->frameHeader(); |
| } |
| |
| // Called when we found user chunks. |
| static int PNGAPI readChunks(png_structp png, png_unknown_chunkp chunk) |
| { |
| static_cast<PNGImageDecoder*>(png_get_user_chunk_ptr(png))->readChunks(chunk); |
| return 1; |
| } |
| #endif |
| |
| class PNGImageReader { |
| WTF_MAKE_FAST_ALLOCATED; |
| public: |
| PNGImageReader(PNGImageDecoder* decoder) |
| : m_readOffset(0) |
| , m_currentBufferSize(0) |
| , m_decodingSizeOnly(false) |
| , m_hasAlpha(false) |
| { |
| m_png = png_create_read_struct(PNG_LIBPNG_VER_STRING, 0, decodingFailed, decodingWarning); |
| m_info = png_create_info_struct(m_png); |
| png_set_progressive_read_fn(m_png, decoder, headerAvailable, rowAvailable, pngComplete); |
| #if ENABLE(APNG) |
| png_byte apngChunks[]= {"acTL\0fcTL\0fdAT\0"}; |
| png_set_keep_unknown_chunks(m_png, 1, apngChunks, 3); |
| png_set_read_user_chunk_fn(m_png, static_cast<png_voidp>(decoder), readChunks); |
| decoder->init(); |
| #endif |
| } |
| |
| ~PNGImageReader() |
| { |
| close(); |
| } |
| |
| void close() |
| { |
| if (m_png && m_info) |
| // This will zero the pointers. |
| png_destroy_read_struct(&m_png, &m_info, 0); |
| m_interlaceBuffer.reset(); |
| m_readOffset = 0; |
| } |
| |
| bool decode(const SharedBuffer::DataSegment& data, bool sizeOnly, unsigned haltAtFrame) |
| { |
| m_decodingSizeOnly = sizeOnly; |
| PNGImageDecoder* decoder = static_cast<PNGImageDecoder*>(png_get_progressive_ptr(m_png)); |
| |
| // We need to do the setjmp here. Otherwise bad things will happen. |
| if (setjmp(JMPBUF(m_png))) |
| return decoder->setFailed(); |
| |
| auto bytesToSkip = m_readOffset; |
| auto bytesToUse = data.size() - bytesToSkip; |
| m_readOffset += bytesToUse; |
| m_currentBufferSize = m_readOffset; |
| png_process_data(m_png, m_info, reinterpret_cast<png_bytep>(const_cast<char*>(data.data() + bytesToSkip)), bytesToUse); |
| // We explicitly specify the superclass encodedDataStatus() because we |
| // merely want to check if we've managed to set the size, not |
| // (recursively) trigger additional decoding if we haven't. |
| if (sizeOnly ? decoder->ScalableImageDecoder::encodedDataStatus() >= EncodedDataStatus::SizeAvailable : decoder->isCompleteAtIndex(haltAtFrame)) |
| return true; |
| |
| return false; |
| } |
| |
| png_structp pngPtr() const { return m_png; } |
| png_infop infoPtr() const { return m_info; } |
| |
| void setReadOffset(unsigned offset) { m_readOffset = offset; } |
| unsigned currentBufferSize() const { return m_currentBufferSize; } |
| bool decodingSizeOnly() const { return m_decodingSizeOnly; } |
| void setHasAlpha(bool hasAlpha) { m_hasAlpha = hasAlpha; } |
| bool hasAlpha() const { return m_hasAlpha; } |
| |
| png_bytep interlaceBuffer() const { return m_interlaceBuffer.get(); } |
| void createInterlaceBuffer(int size) { m_interlaceBuffer = makeUniqueArray<png_byte>(size); } |
| |
| private: |
| png_structp m_png; |
| png_infop m_info; |
| unsigned m_readOffset; |
| unsigned m_currentBufferSize; |
| bool m_decodingSizeOnly; |
| bool m_hasAlpha; |
| UniqueArray<png_byte> m_interlaceBuffer; |
| }; |
| |
| PNGImageDecoder::PNGImageDecoder(AlphaOption alphaOption, GammaAndColorProfileOption gammaAndColorProfileOption) |
| : ScalableImageDecoder(alphaOption, gammaAndColorProfileOption) |
| , m_doNothingOnFailure(false) |
| , m_currentFrame(0) |
| #if ENABLE(APNG) |
| , m_png(nullptr) |
| , m_info(nullptr) |
| , m_isAnimated(false) |
| , m_frameInfo(false) |
| , m_frameIsHidden(false) |
| , m_hasInfo(false) |
| , m_gamma(45455) |
| , m_frameCount(1) |
| , m_playCount(0) |
| , m_totalFrames(0) |
| , m_sizePLTE(0) |
| , m_sizetRNS(0) |
| , m_sequenceNumber(0) |
| , m_width(0) |
| , m_height(0) |
| , m_xOffset(0) |
| , m_yOffset(0) |
| , m_delayNumerator(1) |
| , m_delayDenominator(1) |
| , m_dispose(0) |
| , m_blend(0) |
| #endif |
| { |
| } |
| |
| PNGImageDecoder::~PNGImageDecoder() = default; |
| |
| #if ENABLE(APNG) |
| RepetitionCount PNGImageDecoder::repetitionCount() const |
| { |
| // Signal no repetition if the PNG image is not animated. |
| if (!m_isAnimated) |
| return RepetitionCountNone; |
| |
| // APNG format uses 0 to indicate that an animation must play indefinitely. But |
| // the RepetitionCount enumeration uses RepetitionCountInfinite, so we need to adapt this. |
| if (!m_playCount) |
| return RepetitionCountInfinite; |
| |
| return m_playCount; |
| } |
| #endif |
| |
| ScalableImageDecoderFrame* PNGImageDecoder::frameBufferAtIndex(size_t index) |
| { |
| #if ENABLE(APNG) |
| if (ScalableImageDecoder::encodedDataStatus() < EncodedDataStatus::SizeAvailable) |
| return nullptr; |
| |
| if (index >= frameCount()) |
| index = frameCount() - 1; |
| #else |
| if (index) |
| return nullptr; |
| #endif |
| |
| if (m_frameBufferCache.isEmpty()) |
| m_frameBufferCache.grow(1); |
| |
| auto& frame = m_frameBufferCache[index]; |
| if (!frame.isComplete()) |
| decode(false, index, isAllDataReceived()); |
| return &frame; |
| } |
| |
| bool PNGImageDecoder::setFailed() |
| { |
| if (m_doNothingOnFailure) |
| return false; |
| m_reader = nullptr; |
| return ScalableImageDecoder::setFailed(); |
| } |
| |
| void PNGImageDecoder::headerAvailable() |
| { |
| png_structp png = m_reader->pngPtr(); |
| png_infop info = m_reader->infoPtr(); |
| png_uint_32 width = png_get_image_width(png, info); |
| png_uint_32 height = png_get_image_height(png, info); |
| |
| // Protect against large images. |
| if (width > cMaxPNGSize || height > cMaxPNGSize) { |
| longjmp(JMPBUF(png), 1); |
| return; |
| } |
| |
| // We can fill in the size now that the header is available. Avoid memory |
| // corruption issues by neutering setFailed() during this call; if we don't |
| // do this, failures will cause |m_reader| to be deleted, and our jmpbuf |
| // will cease to exist. Note that we'll still properly set the failure flag |
| // in this case as soon as we longjmp(). |
| m_doNothingOnFailure = true; |
| bool result = setSize(IntSize(width, height)); |
| m_doNothingOnFailure = false; |
| if (!result) { |
| longjmp(JMPBUF(png), 1); |
| return; |
| } |
| |
| int bitDepth, colorType, interlaceType, compressionType, filterType, channels; |
| png_get_IHDR(png, info, &width, &height, &bitDepth, &colorType, &interlaceType, &compressionType, &filterType); |
| |
| // The options we set here match what Mozilla does. |
| |
| #if ENABLE(APNG) |
| m_hasInfo = true; |
| if (m_isAnimated) { |
| png_save_uint_32(m_dataIHDR, 13); |
| memcpy(m_dataIHDR + 4, "IHDR", 4); |
| png_save_uint_32(m_dataIHDR + 8, width); |
| png_save_uint_32(m_dataIHDR + 12, height); |
| m_dataIHDR[16] = bitDepth; |
| m_dataIHDR[17] = colorType; |
| m_dataIHDR[18] = compressionType; |
| m_dataIHDR[19] = filterType; |
| m_dataIHDR[20] = interlaceType; |
| } |
| #endif |
| |
| // Expand to ensure we use 24-bit for RGB and 32-bit for RGBA. |
| if (colorType == PNG_COLOR_TYPE_PALETTE) { |
| #if ENABLE(APNG) |
| if (m_isAnimated) { |
| png_colorp palette; |
| int paletteSize = 0; |
| png_get_PLTE(png, info, &palette, &paletteSize); |
| paletteSize *= 3; |
| png_save_uint_32(m_dataPLTE, paletteSize); |
| memcpy(m_dataPLTE + 4, "PLTE", 4); |
| memcpy(m_dataPLTE + 8, palette, paletteSize); |
| m_sizePLTE = paletteSize + 12; |
| } |
| #endif |
| png_set_expand(png); |
| } |
| |
| if (colorType == PNG_COLOR_TYPE_GRAY && bitDepth < 8) |
| png_set_expand(png); |
| |
| png_bytep trns = 0; |
| int trnsCount = 0; |
| png_color_16p transValues; |
| if (png_get_valid(png, info, PNG_INFO_tRNS)) { |
| png_get_tRNS(png, info, &trns, &trnsCount, &transValues); |
| #if ENABLE(APNG) |
| if (m_isAnimated) { |
| if (colorType == PNG_COLOR_TYPE_RGB) { |
| png_save_uint_16(m_datatRNS + 8, transValues->red); |
| png_save_uint_16(m_datatRNS + 10, transValues->green); |
| png_save_uint_16(m_datatRNS + 12, transValues->blue); |
| trnsCount = 6; |
| } else if (colorType == PNG_COLOR_TYPE_GRAY) { |
| png_save_uint_16(m_datatRNS + 8, transValues->gray); |
| trnsCount = 2; |
| } else if (colorType == PNG_COLOR_TYPE_PALETTE) |
| memcpy(m_datatRNS + 8, trns, trnsCount); |
| |
| png_save_uint_32(m_datatRNS, trnsCount); |
| memcpy(m_datatRNS + 4, "tRNS", 4); |
| m_sizetRNS = trnsCount + 12; |
| } |
| #endif |
| png_set_expand(png); |
| } |
| |
| if (bitDepth == 16) |
| png_set_strip_16(png); |
| |
| if (colorType == PNG_COLOR_TYPE_GRAY || colorType == PNG_COLOR_TYPE_GRAY_ALPHA) |
| png_set_gray_to_rgb(png); |
| |
| // Deal with gamma and keep it under our control. |
| double gamma; |
| if (!m_ignoreGammaAndColorProfile && png_get_gAMA(png, info, &gamma)) { |
| if ((gamma <= 0.0) || (gamma > cMaxGamma)) { |
| gamma = cInverseGamma; |
| png_set_gAMA(png, info, gamma); |
| } |
| png_set_gamma(png, cDefaultGamma, gamma); |
| #if ENABLE(APNG) |
| m_gamma = static_cast<int>(gamma * 100000); |
| #endif |
| } else |
| png_set_gamma(png, cDefaultGamma, cInverseGamma); |
| |
| // Tell libpng to send us rows for interlaced pngs. |
| if (interlaceType == PNG_INTERLACE_ADAM7) |
| png_set_interlace_handling(png); |
| |
| // Update our info now. |
| png_read_update_info(png, info); |
| channels = png_get_channels(png, info); |
| ASSERT(channels == 3 || channels == 4); |
| |
| m_reader->setHasAlpha(channels == 4); |
| |
| if (m_reader->decodingSizeOnly()) { |
| // If we only needed the size, halt the reader. |
| #if defined(PNG_LIBPNG_VER_MAJOR) && defined(PNG_LIBPNG_VER_MINOR) && (PNG_LIBPNG_VER_MAJOR > 1 || (PNG_LIBPNG_VER_MAJOR == 1 && PNG_LIBPNG_VER_MINOR >= 5)) |
| // '0' argument to png_process_data_pause means: Do not cache unprocessed data. |
| m_reader->setReadOffset(m_reader->currentBufferSize() - png_process_data_pause(png, 0)); |
| #else |
| m_reader->setReadOffset(m_reader->currentBufferSize() - png->buffer_size); |
| png->buffer_size = 0; |
| #endif |
| } |
| } |
| |
| void PNGImageDecoder::rowAvailable(unsigned char* rowBuffer, unsigned rowIndex, int) |
| { |
| if (m_frameBufferCache.isEmpty()) |
| return; |
| |
| // Initialize the framebuffer if needed. |
| #if ENABLE(APNG) |
| if (m_currentFrame >= frameCount()) |
| return; |
| #endif |
| auto& buffer = m_frameBufferCache[m_currentFrame]; |
| if (buffer.isInvalid()) { |
| png_structp png = m_reader->pngPtr(); |
| if (!buffer.initialize(size(), m_premultiplyAlpha)) { |
| longjmp(JMPBUF(png), 1); |
| return; |
| } |
| |
| unsigned colorChannels = m_reader->hasAlpha() ? 4 : 3; |
| if (PNG_INTERLACE_ADAM7 == png_get_interlace_type(png, m_reader->infoPtr()) |
| || m_currentFrame) { |
| if (!m_reader->interlaceBuffer()) |
| m_reader->createInterlaceBuffer(colorChannels * size().width() * size().height()); |
| if (!m_reader->interlaceBuffer()) { |
| longjmp(JMPBUF(png), 1); |
| return; |
| } |
| } |
| |
| buffer.setDecodingStatus(DecodingStatus::Partial); |
| buffer.setHasAlpha(false); |
| |
| #if ENABLE(APNG) |
| if (m_currentFrame) |
| initFrameBuffer(m_currentFrame); |
| #endif |
| } |
| |
| /* libpng comments (here to explain what follows). |
| * |
| * 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. |
| */ |
| |
| // Nothing to do if the row is unchanged, or the row is outside |
| // the image bounds: libpng may send extra rows, ignore them to |
| // make our lives easier. |
| if (!rowBuffer) |
| return; |
| if (rowIndex >= (unsigned)size().height()) |
| return; |
| |
| /* libpng comments (continued). |
| * |
| * 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. |
| */ |
| |
| bool hasAlpha = m_reader->hasAlpha(); |
| unsigned colorChannels = hasAlpha ? 4 : 3; |
| png_bytep row = rowBuffer; |
| |
| if (png_bytep interlaceBuffer = m_reader->interlaceBuffer()) { |
| row = interlaceBuffer + (rowIndex * colorChannels * size().width()); |
| #if ENABLE(APNG) |
| if (m_currentFrame) { |
| png_progressive_combine_row(m_png, row, rowBuffer); |
| return; // Only do incremental image display for the first frame. |
| } |
| #endif |
| png_progressive_combine_row(m_reader->pngPtr(), row, rowBuffer); |
| } |
| |
| // Write the decoded row pixels to the frame buffer. |
| auto* address = buffer.backingStore()->pixelAt(0, rowIndex); |
| int width = size().width(); |
| unsigned char nonTrivialAlphaMask = 0; |
| |
| png_bytep pixel = row; |
| if (hasAlpha) { |
| for (int x = 0; x < width; ++x, pixel += 4, ++address) { |
| unsigned alpha = pixel[3]; |
| buffer.backingStore()->setPixel(address, pixel[0], pixel[1], pixel[2], alpha); |
| nonTrivialAlphaMask |= (255 - alpha); |
| } |
| } else { |
| for (int x = 0; x < width; ++x, pixel += 3, ++address) |
| *address = makeRGB(pixel[0], pixel[1], pixel[2]); |
| } |
| |
| if (nonTrivialAlphaMask && !buffer.hasAlpha()) |
| buffer.setHasAlpha(true); |
| } |
| |
| void PNGImageDecoder::pngComplete() |
| { |
| #if ENABLE(APNG) |
| if (m_isAnimated) { |
| if (!processingFinish() && m_frameCount == m_currentFrame) |
| return; |
| |
| fallbackNotAnimated(); |
| } |
| #endif |
| if (!m_frameBufferCache.isEmpty()) |
| m_frameBufferCache.first().setDecodingStatus(DecodingStatus::Complete); |
| } |
| |
| void PNGImageDecoder::decode(bool onlySize, unsigned haltAtFrame, bool allDataReceived) |
| { |
| if (failed()) |
| return; |
| |
| if (!m_reader) |
| m_reader = makeUnique<PNGImageReader>(this); |
| |
| // If we couldn't decode the image but we've received all the data, decoding |
| // has failed. |
| if (!m_reader->decode(*m_data, onlySize, haltAtFrame) && allDataReceived) |
| setFailed(); |
| // If we're done decoding the image, we don't need the PNGImageReader |
| // anymore. (If we failed, |m_reader| has already been cleared.) |
| else if (isComplete()) |
| m_reader = nullptr; |
| } |
| |
| #if ENABLE(APNG) |
| void PNGImageDecoder::readChunks(png_unknown_chunkp chunk) |
| { |
| if (!memcmp(chunk->name, "acTL", 4) && chunk->size == 8) { |
| if (m_hasInfo || m_isAnimated) |
| return; |
| |
| m_frameCount = png_get_uint_32(chunk->data); |
| m_playCount = png_get_uint_32(chunk->data + 4); |
| |
| if (!m_frameCount || m_frameCount > PNG_UINT_31_MAX || m_playCount > PNG_UINT_31_MAX) { |
| fallbackNotAnimated(); |
| return; |
| } |
| |
| m_isAnimated = true; |
| if (!m_frameInfo) |
| m_frameIsHidden = true; |
| |
| if (m_frameBufferCache.size() == m_frameCount) |
| return; |
| |
| m_frameBufferCache.resize(m_frameCount); |
| } else if (!memcmp(chunk->name, "fcTL", 4) && chunk->size == 26) { |
| if (m_hasInfo && !m_isAnimated) |
| return; |
| |
| m_frameInfo = false; |
| |
| if (processingFinish()) { |
| fallbackNotAnimated(); |
| return; |
| } |
| |
| // At this point the old frame is done. Let's start a new one. |
| unsigned sequenceNumber = png_get_uint_32(chunk->data); |
| if (sequenceNumber != m_sequenceNumber++) { |
| fallbackNotAnimated(); |
| return; |
| } |
| |
| m_width = png_get_uint_32(chunk->data + 4); |
| m_height = png_get_uint_32(chunk->data + 8); |
| m_xOffset = png_get_uint_32(chunk->data + 12); |
| m_yOffset = png_get_uint_32(chunk->data + 16); |
| m_delayNumerator = png_get_uint_16(chunk->data + 20); |
| m_delayDenominator = png_get_uint_16(chunk->data + 22); |
| m_dispose = chunk->data[24]; |
| m_blend = chunk->data[25]; |
| |
| png_structp png = m_reader->pngPtr(); |
| png_infop info = m_reader->infoPtr(); |
| png_uint_32 width = png_get_image_width(png, info); |
| png_uint_32 height = png_get_image_height(png, info); |
| |
| if (m_width > cMaxPNGSize || m_height > cMaxPNGSize |
| || m_xOffset > cMaxPNGSize || m_yOffset > cMaxPNGSize |
| || m_xOffset + m_width > width |
| || m_yOffset + m_height > height |
| || m_dispose > 2 || m_blend > 1) { |
| fallbackNotAnimated(); |
| return; |
| } |
| |
| if (m_frameBufferCache.isEmpty()) |
| m_frameBufferCache.grow(1); |
| |
| if (m_currentFrame < m_frameBufferCache.size()) { |
| auto& buffer = m_frameBufferCache[m_currentFrame]; |
| |
| if (!m_delayDenominator) |
| buffer.setDuration(Seconds::fromMilliseconds(m_delayNumerator * 10)); |
| else |
| buffer.setDuration(Seconds::fromMilliseconds(m_delayNumerator * 1000 / m_delayDenominator)); |
| |
| if (m_dispose == 2) |
| buffer.setDisposalMethod(ScalableImageDecoderFrame::DisposalMethod::RestoreToPrevious); |
| else if (m_dispose == 1) |
| buffer.setDisposalMethod(ScalableImageDecoderFrame::DisposalMethod::RestoreToBackground); |
| else |
| buffer.setDisposalMethod(ScalableImageDecoderFrame::DisposalMethod::DoNotDispose); |
| } |
| |
| m_frameInfo = true; |
| m_frameIsHidden = false; |
| |
| if (processingStart(chunk)) { |
| fallbackNotAnimated(); |
| return; |
| } |
| } else if (!memcmp(chunk->name, "fdAT", 4) && chunk->size >= 4) { |
| if (!m_frameInfo || !m_isAnimated) |
| return; |
| |
| unsigned sequenceNumber = png_get_uint_32(chunk->data); |
| if (sequenceNumber != m_sequenceNumber++) { |
| fallbackNotAnimated(); |
| return; |
| } |
| |
| if (setjmp(JMPBUF(m_png))) { |
| fallbackNotAnimated(); |
| return; |
| } |
| |
| png_save_uint_32(chunk->data, chunk->size - 4); |
| png_process_data(m_png, m_info, chunk->data, 4); |
| memcpy(chunk->data, "IDAT", 4); |
| png_process_data(m_png, m_info, chunk->data, chunk->size); |
| png_process_data(m_png, m_info, chunk->data, 4); |
| } |
| } |
| |
| void PNGImageDecoder::frameHeader() |
| { |
| int colorType = png_get_color_type(m_png, m_info); |
| |
| if (colorType == PNG_COLOR_TYPE_PALETTE) |
| png_set_expand(m_png); |
| |
| int bitDepth = png_get_bit_depth(m_png, m_info); |
| if (colorType == PNG_COLOR_TYPE_GRAY && bitDepth < 8) |
| png_set_expand(m_png); |
| |
| if (png_get_valid(m_png, m_info, PNG_INFO_tRNS)) |
| png_set_expand(m_png); |
| |
| if (bitDepth == 16) |
| png_set_strip_16(m_png); |
| |
| if (colorType == PNG_COLOR_TYPE_GRAY || colorType == PNG_COLOR_TYPE_GRAY_ALPHA) |
| png_set_gray_to_rgb(m_png); |
| |
| double gamma; |
| if (png_get_gAMA(m_png, m_info, &gamma)) |
| png_set_gamma(m_png, cDefaultGamma, gamma); |
| |
| png_set_interlace_handling(m_png); |
| |
| png_read_update_info(m_png, m_info); |
| } |
| |
| void PNGImageDecoder::init() |
| { |
| m_isAnimated = false; |
| m_frameInfo = false; |
| m_frameIsHidden = false; |
| m_hasInfo = false; |
| m_currentFrame = 0; |
| m_totalFrames = 0; |
| m_sequenceNumber = 0; |
| } |
| |
| void PNGImageDecoder::clearFrameBufferCache(size_t clearBeforeFrame) |
| { |
| if (m_frameBufferCache.isEmpty()) |
| return; |
| |
| // See GIFImageDecoder for full explanation. |
| clearBeforeFrame = std::min(clearBeforeFrame, m_frameBufferCache.size() - 1); |
| const Vector<ScalableImageDecoderFrame>::iterator end(m_frameBufferCache.begin() + clearBeforeFrame); |
| |
| Vector<ScalableImageDecoderFrame>::iterator i(end); |
| for (; (i != m_frameBufferCache.begin()) && (i->isInvalid() || (i->disposalMethod() == ScalableImageDecoderFrame::DisposalMethod::RestoreToPrevious)); --i) { |
| if (i->isComplete() && (i != end)) |
| i->clear(); |
| } |
| |
| // Now |i| holds the last frame we need to preserve; clear prior frames. |
| for (Vector<ScalableImageDecoderFrame>::iterator j(m_frameBufferCache.begin()); j != i; ++j) { |
| ASSERT(!j->isPartial()); |
| if (j->isInvalid()) |
| j->clear(); |
| } |
| } |
| |
| void PNGImageDecoder::initFrameBuffer(size_t frameIndex) |
| { |
| if (frameIndex >= frameCount()) |
| return; |
| |
| auto& buffer = m_frameBufferCache[frameIndex]; |
| |
| // The starting state for this frame depends on the previous frame's |
| // disposal method. |
| // |
| // Frames that use the DisposalMethod::RestoreToPrevious method are effectively |
| // no-ops in terms of changing the starting state of a frame compared to |
| // the starting state of the previous frame, so skip over them. (If the |
| // first frame specifies this method, it will get treated like |
| // DisposeOverwriteBgcolor below and reset to a completely empty image.) |
| const auto* prevBuffer = &m_frameBufferCache[--frameIndex]; |
| auto prevMethod = prevBuffer->disposalMethod(); |
| while (frameIndex && (prevMethod == ScalableImageDecoderFrame::DisposalMethod::RestoreToPrevious)) { |
| prevBuffer = &m_frameBufferCache[--frameIndex]; |
| prevMethod = prevBuffer->disposalMethod(); |
| } |
| |
| png_structp png = m_reader->pngPtr(); |
| ASSERT(prevBuffer->isComplete()); |
| |
| if (prevMethod == ScalableImageDecoderFrame::DisposalMethod::DoNotDispose) { |
| // Preserve the last frame as the starting state for this frame. |
| if (!prevBuffer->backingStore() || !buffer.initialize(*prevBuffer->backingStore())) |
| longjmp(JMPBUF(png), 1); |
| } else { |
| // We want to clear the previous frame to transparent, without |
| // affecting pixels in the image outside of the frame. |
| IntRect prevRect = prevBuffer->backingStore()->frameRect(); |
| if (!frameIndex || prevRect.contains(IntRect(IntPoint(), size()))) { |
| // Clearing the first frame, or a frame the size of the whole |
| // image, results in a completely empty image. |
| buffer.backingStore()->clear(); |
| buffer.setHasAlpha(true); |
| } else { |
| // Copy the whole previous buffer, then clear just its frame. |
| if (!prevBuffer->backingStore() || !buffer.initialize(*prevBuffer->backingStore())) { |
| longjmp(JMPBUF(png), 1); |
| return; |
| } |
| buffer.backingStore()->clearRect(prevRect); |
| buffer.setHasAlpha(true); |
| } |
| } |
| |
| IntRect frameRect(m_xOffset, m_yOffset, m_width, m_height); |
| |
| // Make sure the frameRect doesn't extend outside the buffer. |
| if (frameRect.maxX() > size().width()) |
| frameRect.setWidth(size().width() - m_xOffset); |
| if (frameRect.maxY() > size().height()) |
| frameRect.setHeight(size().height() - m_yOffset); |
| |
| buffer.backingStore()->setFrameRect(frameRect); |
| } |
| |
| void PNGImageDecoder::frameComplete() |
| { |
| if (m_frameIsHidden || m_currentFrame >= frameCount()) |
| return; |
| |
| auto& buffer = m_frameBufferCache[m_currentFrame]; |
| buffer.setDecodingStatus(DecodingStatus::Complete); |
| |
| png_bytep interlaceBuffer = m_reader->interlaceBuffer(); |
| |
| if (m_currentFrame && interlaceBuffer) { |
| IntRect rect = buffer.backingStore()->frameRect(); |
| bool hasAlpha = m_reader->hasAlpha(); |
| unsigned colorChannels = hasAlpha ? 4 : 3; |
| bool nonTrivialAlpha = false; |
| if (m_blend && !hasAlpha) |
| m_blend = 0; |
| |
| png_bytep row = interlaceBuffer; |
| for (int y = rect.y(); y < rect.maxY(); ++y, row += colorChannels * size().width()) { |
| png_bytep pixel = row; |
| auto* address = buffer.backingStore()->pixelAt(rect.x(), y); |
| for (int x = rect.x(); x < rect.maxX(); ++x, pixel += colorChannels) { |
| unsigned alpha = hasAlpha ? pixel[3] : 255; |
| nonTrivialAlpha |= alpha < 255; |
| if (!m_blend) |
| buffer.backingStore()->setPixel(address++, pixel[0], pixel[1], pixel[2], alpha); |
| else |
| buffer.backingStore()->blendPixel(address++, pixel[0], pixel[1], pixel[2], alpha); |
| } |
| } |
| |
| if (!nonTrivialAlpha) { |
| IntRect rect = buffer.backingStore()->frameRect(); |
| if (rect.contains(IntRect(IntPoint(), size()))) |
| buffer.setHasAlpha(false); |
| else { |
| size_t frameIndex = m_currentFrame; |
| const auto* prevBuffer = &m_frameBufferCache[--frameIndex]; |
| while (frameIndex && (prevBuffer->disposalMethod() == ScalableImageDecoderFrame::DisposalMethod::RestoreToPrevious)) |
| prevBuffer = &m_frameBufferCache[--frameIndex]; |
| |
| IntRect prevRect = prevBuffer->backingStore()->frameRect(); |
| if ((prevBuffer->disposalMethod() == ScalableImageDecoderFrame::DisposalMethod::RestoreToBackground) && !prevBuffer->hasAlpha() && rect.contains(prevRect)) |
| buffer.setHasAlpha(false); |
| } |
| } else if (!m_blend && !buffer.hasAlpha()) |
| buffer.setHasAlpha(nonTrivialAlpha); |
| } |
| m_currentFrame++; |
| } |
| |
| int PNGImageDecoder::processingStart(png_unknown_chunkp chunk) |
| { |
| static png_byte dataPNG[8] = {137, 80, 78, 71, 13, 10, 26, 10}; |
| static png_byte datagAMA[16] = {0, 0, 0, 4, 103, 65, 77, 65}; |
| |
| if (!m_hasInfo) |
| return 0; |
| |
| m_totalFrames++; |
| |
| m_png = png_create_read_struct(PNG_LIBPNG_VER_STRING, 0, decodingFailed, 0); |
| m_info = png_create_info_struct(m_png); |
| if (setjmp(JMPBUF(m_png))) |
| return 1; |
| |
| png_set_crc_action(m_png, PNG_CRC_QUIET_USE, PNG_CRC_QUIET_USE); |
| png_set_progressive_read_fn(m_png, static_cast<png_voidp>(this), |
| WebCore::frameHeader, WebCore::rowAvailable, 0); |
| |
| memcpy(m_dataIHDR + 8, chunk->data + 4, 8); |
| png_save_uint_32(datagAMA + 8, m_gamma); |
| |
| png_process_data(m_png, m_info, dataPNG, 8); |
| png_process_data(m_png, m_info, m_dataIHDR, 25); |
| png_process_data(m_png, m_info, datagAMA, 16); |
| if (m_sizePLTE > 0) |
| png_process_data(m_png, m_info, m_dataPLTE, m_sizePLTE); |
| if (m_sizetRNS > 0) |
| png_process_data(m_png, m_info, m_datatRNS, m_sizetRNS); |
| |
| return 0; |
| } |
| |
| int PNGImageDecoder::processingFinish() |
| { |
| static png_byte dataIEND[12] = {0, 0, 0, 0, 73, 69, 78, 68, 174, 66, 96, 130}; |
| |
| if (!m_hasInfo) |
| return 0; |
| |
| if (m_totalFrames) { |
| if (setjmp(JMPBUF(m_png))) |
| return 1; |
| |
| png_process_data(m_png, m_info, dataIEND, 12); |
| png_destroy_read_struct(&m_png, &m_info, 0); |
| } |
| |
| frameComplete(); |
| return 0; |
| } |
| |
| void PNGImageDecoder::fallbackNotAnimated() |
| { |
| m_isAnimated = false; |
| m_playCount = 0; |
| m_currentFrame = 0; |
| } |
| #endif |
| |
| } // namespace WebCore |
