зеркало из https://github.com/mozilla/gecko-dev.git
1133 строки
35 KiB
C++
1133 строки
35 KiB
C++
/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
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*
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* This Source Code Form is subject to the terms of the Mozilla Public
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* License, v. 2.0. If a copy of the MPL was not distributed with this
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* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
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#include "ImageLogging.h" // Must appear first
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#include "nsPNGDecoder.h"
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#include <algorithm>
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#include <cstdint>
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#include "gfxColor.h"
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#include "gfxPlatform.h"
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#include "imgFrame.h"
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#include "nsColor.h"
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#include "nsIInputStream.h"
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#include "nsMemory.h"
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#include "nsRect.h"
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#include "nspr.h"
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#include "png.h"
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#include "RasterImage.h"
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#include "SurfaceCache.h"
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#include "SurfacePipeFactory.h"
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#include "mozilla/DebugOnly.h"
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#include "mozilla/Telemetry.h"
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using namespace mozilla::gfx;
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using std::min;
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namespace mozilla {
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namespace image {
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static LazyLogModule sPNGLog("PNGDecoder");
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static LazyLogModule sPNGDecoderAccountingLog("PNGDecoderAccounting");
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// limit image dimensions (bug #251381, #591822, #967656, and #1283961)
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#ifndef MOZ_PNG_MAX_WIDTH
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# define MOZ_PNG_MAX_WIDTH 0x7fffffff // Unlimited
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#endif
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#ifndef MOZ_PNG_MAX_HEIGHT
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# define MOZ_PNG_MAX_HEIGHT 0x7fffffff // Unlimited
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#endif
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nsPNGDecoder::AnimFrameInfo::AnimFrameInfo()
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: mDispose(DisposalMethod::KEEP)
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, mBlend(BlendMethod::OVER)
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, mTimeout(0)
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{ }
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#ifdef PNG_APNG_SUPPORTED
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int32_t GetNextFrameDelay(png_structp aPNG, png_infop aInfo)
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{
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// Delay, in seconds, is delayNum / delayDen.
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png_uint_16 delayNum = png_get_next_frame_delay_num(aPNG, aInfo);
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png_uint_16 delayDen = png_get_next_frame_delay_den(aPNG, aInfo);
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if (delayNum == 0) {
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return 0; // SetFrameTimeout() will set to a minimum.
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}
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if (delayDen == 0) {
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delayDen = 100; // So says the APNG spec.
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}
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// Need to cast delay_num to float to have a proper division and
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// the result to int to avoid a compiler warning.
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return static_cast<int32_t>(static_cast<double>(delayNum) * 1000 / delayDen);
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}
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nsPNGDecoder::AnimFrameInfo::AnimFrameInfo(png_structp aPNG, png_infop aInfo)
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: mDispose(DisposalMethod::KEEP)
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, mBlend(BlendMethod::OVER)
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, mTimeout(0)
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{
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png_byte dispose_op = png_get_next_frame_dispose_op(aPNG, aInfo);
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png_byte blend_op = png_get_next_frame_blend_op(aPNG, aInfo);
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if (dispose_op == PNG_DISPOSE_OP_PREVIOUS) {
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mDispose = DisposalMethod::RESTORE_PREVIOUS;
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} else if (dispose_op == PNG_DISPOSE_OP_BACKGROUND) {
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mDispose = DisposalMethod::CLEAR;
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} else {
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mDispose = DisposalMethod::KEEP;
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}
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if (blend_op == PNG_BLEND_OP_SOURCE) {
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mBlend = BlendMethod::SOURCE;
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} else {
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mBlend = BlendMethod::OVER;
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}
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mTimeout = GetNextFrameDelay(aPNG, aInfo);
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}
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#endif
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// First 8 bytes of a PNG file
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const uint8_t
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nsPNGDecoder::pngSignatureBytes[] = { 137, 80, 78, 71, 13, 10, 26, 10 };
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nsPNGDecoder::nsPNGDecoder(RasterImage* aImage)
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: Decoder(aImage)
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, mLexer(Transition::ToUnbuffered(State::FINISHED_PNG_DATA,
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State::PNG_DATA,
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SIZE_MAX),
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Transition::TerminateSuccess())
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, mNextTransition(Transition::ContinueUnbuffered(State::PNG_DATA))
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, mLastChunkLength(0)
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, mPNG(nullptr)
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, mInfo(nullptr)
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, mCMSLine(nullptr)
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, interlacebuf(nullptr)
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, mInProfile(nullptr)
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, mTransform(nullptr)
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, mFormat(SurfaceFormat::UNKNOWN)
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, mCMSMode(0)
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, mChannels(0)
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, mPass(0)
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, mFrameIsHidden(false)
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, mDisablePremultipliedAlpha(false)
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, mNumFrames(0)
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{ }
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nsPNGDecoder::~nsPNGDecoder()
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{
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if (mPNG) {
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png_destroy_read_struct(&mPNG, mInfo ? &mInfo : nullptr, nullptr);
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}
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if (mCMSLine) {
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free(mCMSLine);
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}
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if (interlacebuf) {
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free(interlacebuf);
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}
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if (mInProfile) {
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qcms_profile_release(mInProfile);
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// mTransform belongs to us only if mInProfile is non-null
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if (mTransform) {
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qcms_transform_release(mTransform);
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}
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}
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}
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nsPNGDecoder::TransparencyType
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nsPNGDecoder::GetTransparencyType(const IntRect& aFrameRect)
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{
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// Check if the image has a transparent color in its palette.
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if (HasAlphaChannel()) {
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return TransparencyType::eAlpha;
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}
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if (!aFrameRect.IsEqualEdges(FullFrame())) {
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MOZ_ASSERT(HasAnimation());
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return TransparencyType::eFrameRect;
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}
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return TransparencyType::eNone;
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}
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void
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nsPNGDecoder::PostHasTransparencyIfNeeded(TransparencyType aTransparencyType)
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{
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switch (aTransparencyType) {
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case TransparencyType::eNone:
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return;
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case TransparencyType::eAlpha:
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PostHasTransparency();
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return;
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case TransparencyType::eFrameRect:
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// If the first frame of animated image doesn't draw into the whole image,
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// then record that it is transparent. For subsequent frames, this doesn't
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// affect transparency, because they're composited on top of all previous
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// frames.
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if (mNumFrames == 0) {
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PostHasTransparency();
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}
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return;
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}
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}
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// CreateFrame() is used for both simple and animated images.
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nsresult
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nsPNGDecoder::CreateFrame(const FrameInfo& aFrameInfo)
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{
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MOZ_ASSERT(HasSize());
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MOZ_ASSERT(!IsMetadataDecode());
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// Check if we have transparency, and send notifications if needed.
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auto transparency = GetTransparencyType(aFrameInfo.mFrameRect);
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PostHasTransparencyIfNeeded(transparency);
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mFormat = transparency == TransparencyType::eNone
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? SurfaceFormat::B8G8R8X8
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: SurfaceFormat::B8G8R8A8;
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// Make sure there's no animation or padding if we're downscaling.
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MOZ_ASSERT_IF(Size() != OutputSize(), mNumFrames == 0);
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MOZ_ASSERT_IF(Size() != OutputSize(), !GetImageMetadata().HasAnimation());
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MOZ_ASSERT_IF(Size() != OutputSize(),
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transparency != TransparencyType::eFrameRect);
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Maybe<AnimationParams> animParams;
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#ifdef PNG_APNG_SUPPORTED
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if (png_get_valid(mPNG, mInfo, PNG_INFO_acTL)) {
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mAnimInfo = AnimFrameInfo(mPNG, mInfo);
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if (mAnimInfo.mDispose == DisposalMethod::CLEAR) {
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// We may have to display the background under this image during
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// animation playback, so we regard it as transparent.
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PostHasTransparency();
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}
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animParams.emplace(AnimationParams {
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aFrameInfo.mFrameRect,
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FrameTimeout::FromRawMilliseconds(mAnimInfo.mTimeout),
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mNumFrames, mAnimInfo.mBlend, mAnimInfo.mDispose
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});
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}
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#endif
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// If this image is interlaced, we can display better quality intermediate
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// results to the user by post processing them with ADAM7InterpolatingFilter.
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SurfacePipeFlags pipeFlags = aFrameInfo.mIsInterlaced
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? SurfacePipeFlags::ADAM7_INTERPOLATE
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: SurfacePipeFlags();
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if (mNumFrames == 0) {
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// The first frame may be displayed progressively.
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pipeFlags |= SurfacePipeFlags::PROGRESSIVE_DISPLAY;
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}
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Maybe<SurfacePipe> pipe =
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SurfacePipeFactory::CreateSurfacePipe(this, Size(), OutputSize(),
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aFrameInfo.mFrameRect, mFormat,
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animParams, pipeFlags);
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if (!pipe) {
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mPipe = SurfacePipe();
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return NS_ERROR_FAILURE;
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}
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mPipe = Move(*pipe);
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mFrameRect = aFrameInfo.mFrameRect;
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mPass = 0;
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MOZ_LOG(sPNGDecoderAccountingLog, LogLevel::Debug,
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("PNGDecoderAccounting: nsPNGDecoder::CreateFrame -- created "
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"image frame with %dx%d pixels for decoder %p",
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mFrameRect.Width(), mFrameRect.Height(), this));
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return NS_OK;
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}
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// set timeout and frame disposal method for the current frame
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void
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nsPNGDecoder::EndImageFrame()
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{
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if (mFrameIsHidden) {
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return;
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}
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mNumFrames++;
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Opacity opacity = mFormat == SurfaceFormat::B8G8R8X8
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? Opacity::FULLY_OPAQUE
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: Opacity::SOME_TRANSPARENCY;
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PostFrameStop(opacity);
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}
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nsresult
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nsPNGDecoder::InitInternal()
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{
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mCMSMode = gfxPlatform::GetCMSMode();
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if (GetSurfaceFlags() & SurfaceFlags::NO_COLORSPACE_CONVERSION) {
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mCMSMode = eCMSMode_Off;
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}
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mDisablePremultipliedAlpha =
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bool(GetSurfaceFlags() & SurfaceFlags::NO_PREMULTIPLY_ALPHA);
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#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
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static png_byte color_chunks[]=
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{ 99, 72, 82, 77, '\0', // cHRM
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105, 67, 67, 80, '\0'}; // iCCP
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static png_byte unused_chunks[]=
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{ 98, 75, 71, 68, '\0', // bKGD
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101, 88, 73, 102, '\0', // eXIf
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104, 73, 83, 84, '\0', // hIST
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105, 84, 88, 116, '\0', // iTXt
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111, 70, 70, 115, '\0', // oFFs
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112, 67, 65, 76, '\0', // pCAL
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115, 67, 65, 76, '\0', // sCAL
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112, 72, 89, 115, '\0', // pHYs
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115, 66, 73, 84, '\0', // sBIT
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115, 80, 76, 84, '\0', // sPLT
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116, 69, 88, 116, '\0', // tEXt
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116, 73, 77, 69, '\0', // tIME
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122, 84, 88, 116, '\0'}; // zTXt
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#endif
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// Initialize the container's source image header
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// Always decode to 24 bit pixdepth
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mPNG = png_create_read_struct(PNG_LIBPNG_VER_STRING,
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nullptr, nsPNGDecoder::error_callback,
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nsPNGDecoder::warning_callback);
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if (!mPNG) {
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return NS_ERROR_OUT_OF_MEMORY;
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}
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mInfo = png_create_info_struct(mPNG);
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if (!mInfo) {
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png_destroy_read_struct(&mPNG, nullptr, nullptr);
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return NS_ERROR_OUT_OF_MEMORY;
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}
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#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
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// Ignore unused chunks
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if (mCMSMode == eCMSMode_Off || IsMetadataDecode()) {
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png_set_keep_unknown_chunks(mPNG, 1, color_chunks, 2);
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}
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png_set_keep_unknown_chunks(mPNG, 1, unused_chunks,
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(int)sizeof(unused_chunks)/5);
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#endif
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#ifdef PNG_SET_USER_LIMITS_SUPPORTED
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png_set_user_limits(mPNG, MOZ_PNG_MAX_WIDTH, MOZ_PNG_MAX_HEIGHT);
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if (mCMSMode != eCMSMode_Off) {
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png_set_chunk_malloc_max(mPNG, 4000000L);
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}
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#endif
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#ifdef PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED
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// Disallow palette-index checking, for speed; we would ignore the warning
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// anyhow. This feature was added at libpng version 1.5.10 and is disabled
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// in the embedded libpng but enabled by default in the system libpng. This
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// call also disables it in the system libpng, for decoding speed.
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// Bug #745202.
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png_set_check_for_invalid_index(mPNG, 0);
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#endif
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#ifdef PNG_SET_OPTION_SUPPORTED
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#if defined(PNG_sRGB_PROFILE_CHECKS) && PNG_sRGB_PROFILE_CHECKS >= 0
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// Skip checking of sRGB ICC profiles
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png_set_option(mPNG, PNG_SKIP_sRGB_CHECK_PROFILE, PNG_OPTION_ON);
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#endif
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#ifdef PNG_MAXIMUM_INFLATE_WINDOW
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// Force a larger zlib inflate window as some images in the wild have
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// incorrectly set metadata (specifically CMF bits) which prevent us from
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// decoding them otherwise.
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png_set_option(mPNG, PNG_MAXIMUM_INFLATE_WINDOW, PNG_OPTION_ON);
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#endif
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#endif
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// use this as libpng "progressive pointer" (retrieve in callbacks)
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png_set_progressive_read_fn(mPNG, static_cast<png_voidp>(this),
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nsPNGDecoder::info_callback,
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nsPNGDecoder::row_callback,
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nsPNGDecoder::end_callback);
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return NS_OK;
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}
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LexerResult
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nsPNGDecoder::DoDecode(SourceBufferIterator& aIterator, IResumable* aOnResume)
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{
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MOZ_ASSERT(!HasError(), "Shouldn't call DoDecode after error!");
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return mLexer.Lex(aIterator, aOnResume,
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[=](State aState, const char* aData, size_t aLength) {
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switch (aState) {
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case State::PNG_DATA:
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return ReadPNGData(aData, aLength);
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case State::FINISHED_PNG_DATA:
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return FinishedPNGData();
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}
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MOZ_CRASH("Unknown State");
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});
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}
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LexerTransition<nsPNGDecoder::State>
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nsPNGDecoder::ReadPNGData(const char* aData, size_t aLength)
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{
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// If we were waiting until after returning from a yield to call
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// CreateFrame(), call it now.
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if (mNextFrameInfo) {
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if (NS_FAILED(CreateFrame(*mNextFrameInfo))) {
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return Transition::TerminateFailure();
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}
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MOZ_ASSERT(mImageData, "Should have a buffer now");
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mNextFrameInfo = Nothing();
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}
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// libpng uses setjmp/longjmp for error handling.
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if (setjmp(png_jmpbuf(mPNG))) {
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return Transition::TerminateFailure();
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}
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// Pass the data off to libpng.
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mLastChunkLength = aLength;
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mNextTransition = Transition::ContinueUnbuffered(State::PNG_DATA);
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png_process_data(mPNG, mInfo,
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reinterpret_cast<unsigned char*>(const_cast<char*>((aData))),
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aLength);
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// Make sure that we've reached a terminal state if decoding is done.
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MOZ_ASSERT_IF(GetDecodeDone(), mNextTransition.NextStateIsTerminal());
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MOZ_ASSERT_IF(HasError(), mNextTransition.NextStateIsTerminal());
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// Continue with whatever transition the callback code requested. We
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// initialized this to Transition::ContinueUnbuffered(State::PNG_DATA) above,
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// so by default we just continue the unbuffered read.
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return mNextTransition;
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}
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LexerTransition<nsPNGDecoder::State>
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nsPNGDecoder::FinishedPNGData()
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{
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// Since we set up an unbuffered read for SIZE_MAX bytes, if we actually read
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// all that data something is really wrong.
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MOZ_ASSERT_UNREACHABLE("Read the entire address space?");
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return Transition::TerminateFailure();
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}
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// Sets up gamma pre-correction in libpng before our callback gets called.
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// We need to do this if we don't end up with a CMS profile.
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static void
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PNGDoGammaCorrection(png_structp png_ptr, png_infop info_ptr)
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{
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double aGamma;
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if (png_get_gAMA(png_ptr, info_ptr, &aGamma)) {
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if ((aGamma <= 0.0) || (aGamma > 21474.83)) {
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aGamma = 0.45455;
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png_set_gAMA(png_ptr, info_ptr, aGamma);
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}
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png_set_gamma(png_ptr, 2.2, aGamma);
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} else {
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png_set_gamma(png_ptr, 2.2, 0.45455);
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}
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}
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// Adapted from http://www.littlecms.com/pngchrm.c example code
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static qcms_profile*
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PNGGetColorProfile(png_structp png_ptr, png_infop info_ptr,
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int color_type, qcms_data_type* inType, uint32_t* intent)
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{
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qcms_profile* profile = nullptr;
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*intent = QCMS_INTENT_PERCEPTUAL; // Our default
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// First try to see if iCCP chunk is present
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if (png_get_valid(png_ptr, info_ptr, PNG_INFO_iCCP)) {
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png_uint_32 profileLen;
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png_bytep profileData;
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png_charp profileName;
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int compression;
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png_get_iCCP(png_ptr, info_ptr, &profileName, &compression,
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&profileData, &profileLen);
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profile = qcms_profile_from_memory((char*)profileData, profileLen);
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if (profile) {
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uint32_t profileSpace = qcms_profile_get_color_space(profile);
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bool mismatch = false;
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if (color_type & PNG_COLOR_MASK_COLOR) {
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if (profileSpace != icSigRgbData) {
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mismatch = true;
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}
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} else {
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if (profileSpace == icSigRgbData) {
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png_set_gray_to_rgb(png_ptr);
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} else if (profileSpace != icSigGrayData) {
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mismatch = true;
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}
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}
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if (mismatch) {
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qcms_profile_release(profile);
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profile = nullptr;
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} else {
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*intent = qcms_profile_get_rendering_intent(profile);
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}
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}
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}
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// Check sRGB chunk
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if (!profile && png_get_valid(png_ptr, info_ptr, PNG_INFO_sRGB)) {
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profile = qcms_profile_sRGB();
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if (profile) {
|
|
int fileIntent;
|
|
png_set_gray_to_rgb(png_ptr);
|
|
png_get_sRGB(png_ptr, info_ptr, &fileIntent);
|
|
uint32_t 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) {
|
|
uint32_t 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)
|
|
{
|
|
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);
|
|
|
|
const IntRect frameRect(0, 0, width, height);
|
|
|
|
// Post our size to the superclass
|
|
decoder->PostSize(frameRect.Width(), frameRect.Height());
|
|
|
|
if (width >
|
|
SurfaceCache::MaximumCapacity()/(bit_depth > 8 ? 16:8)) {
|
|
// libpng needs space to allocate two row buffers
|
|
png_error(decoder->mPNG, "Image is too wide");
|
|
}
|
|
|
|
if (decoder->HasError()) {
|
|
// Setting the size led to an error.
|
|
png_error(decoder->mPNG, "Sizing error");
|
|
}
|
|
|
|
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.
|
|
const bool isInterlaced = interlace_type == PNG_INTERLACE_ADAM7;
|
|
if (isInterlaced) {
|
|
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 > 4) {
|
|
png_error(decoder->mPNG, "Invalid number of channels");
|
|
}
|
|
|
|
#ifdef PNG_APNG_SUPPORTED
|
|
bool isAnimated = png_get_valid(png_ptr, info_ptr, PNG_INFO_acTL);
|
|
if (isAnimated) {
|
|
int32_t rawTimeout = GetNextFrameDelay(png_ptr, info_ptr);
|
|
decoder->PostIsAnimated(FrameTimeout::FromRawMilliseconds(rawTimeout));
|
|
|
|
if (decoder->Size() != decoder->OutputSize() &&
|
|
!decoder->IsFirstFrameDecode()) {
|
|
MOZ_ASSERT_UNREACHABLE("Doing downscale-during-decode "
|
|
"for an animated image?");
|
|
png_error(decoder->mPNG, "Invalid downscale attempt"); // Abort decode.
|
|
}
|
|
}
|
|
#endif
|
|
|
|
if (decoder->IsMetadataDecode()) {
|
|
// If we are animated then the first frame rect is either:
|
|
// 1) the whole image if the IDAT chunk is part of the animation
|
|
// 2) the frame rect of the first fDAT chunk otherwise.
|
|
// If we are not animated then we want to make sure to call
|
|
// PostHasTransparency in the metadata decode if we need to. So it's
|
|
// okay to pass IntRect(0, 0, width, height) here for animated images;
|
|
// they will call with the proper first frame rect in the full decode.
|
|
auto transparency = decoder->GetTransparencyType(frameRect);
|
|
decoder->PostHasTransparencyIfNeeded(transparency);
|
|
|
|
// We have the metadata we're looking for, so stop here, before we allocate
|
|
// buffers below.
|
|
return decoder->DoTerminate(png_ptr, TerminalState::SUCCESS);
|
|
}
|
|
|
|
#ifdef PNG_APNG_SUPPORTED
|
|
if (isAnimated) {
|
|
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
|
|
nsresult rv = decoder->CreateFrame(FrameInfo{ frameRect,
|
|
isInterlaced });
|
|
if (NS_FAILED(rv)) {
|
|
png_error(decoder->mPNG, "CreateFrame failed");
|
|
}
|
|
MOZ_ASSERT(decoder->mImageData, "Should have a buffer now");
|
|
#ifdef PNG_APNG_SUPPORTED
|
|
}
|
|
#endif
|
|
|
|
if (decoder->mTransform && (channels <= 2 || isInterlaced)) {
|
|
uint32_t bpp[] = { 0, 3, 4, 3, 4 };
|
|
decoder->mCMSLine =
|
|
static_cast<uint8_t*>(malloc(bpp[channels] * frameRect.Width()));
|
|
if (!decoder->mCMSLine) {
|
|
png_error(decoder->mPNG, "malloc of mCMSLine failed");
|
|
}
|
|
}
|
|
|
|
if (interlace_type == PNG_INTERLACE_ADAM7) {
|
|
if (frameRect.Height() < INT32_MAX / (frameRect.Width() * int32_t(channels))) {
|
|
const size_t bufferSize = channels * frameRect.Width() * frameRect.Height();
|
|
|
|
if (bufferSize > SurfaceCache::MaximumCapacity()) {
|
|
png_error(decoder->mPNG, "Insufficient memory to deinterlace image");
|
|
}
|
|
|
|
decoder->interlacebuf = static_cast<uint8_t*>(malloc(bufferSize));
|
|
}
|
|
if (!decoder->interlacebuf) {
|
|
png_error(decoder->mPNG, "malloc of interlacebuf failed");
|
|
}
|
|
}
|
|
}
|
|
|
|
void
|
|
nsPNGDecoder::PostInvalidationIfNeeded()
|
|
{
|
|
Maybe<SurfaceInvalidRect> invalidRect = mPipe.TakeInvalidRect();
|
|
if (!invalidRect) {
|
|
return;
|
|
}
|
|
|
|
PostInvalidation(invalidRect->mInputSpaceRect,
|
|
Some(invalidRect->mOutputSpaceRect));
|
|
}
|
|
|
|
static NextPixel<uint32_t>
|
|
PackRGBPixelAndAdvance(uint8_t*& aRawPixelInOut)
|
|
{
|
|
const uint32_t pixel =
|
|
gfxPackedPixel(0xFF, aRawPixelInOut[0], aRawPixelInOut[1],
|
|
aRawPixelInOut[2]);
|
|
aRawPixelInOut += 3;
|
|
return AsVariant(pixel);
|
|
}
|
|
|
|
static NextPixel<uint32_t>
|
|
PackRGBAPixelAndAdvance(uint8_t*& aRawPixelInOut)
|
|
{
|
|
const uint32_t pixel =
|
|
gfxPackedPixel(aRawPixelInOut[3], aRawPixelInOut[0],
|
|
aRawPixelInOut[1], aRawPixelInOut[2]);
|
|
aRawPixelInOut += 4;
|
|
return AsVariant(pixel);
|
|
}
|
|
|
|
static NextPixel<uint32_t>
|
|
PackUnpremultipliedRGBAPixelAndAdvance(uint8_t*& aRawPixelInOut)
|
|
{
|
|
const uint32_t pixel =
|
|
gfxPackedPixelNoPreMultiply(aRawPixelInOut[3], aRawPixelInOut[0],
|
|
aRawPixelInOut[1], aRawPixelInOut[2]);
|
|
aRawPixelInOut += 4;
|
|
return AsVariant(pixel);
|
|
}
|
|
|
|
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
|
|
* nullptr. 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-nullptr 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 nullptr 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));
|
|
|
|
if (decoder->mFrameIsHidden) {
|
|
return; // Skip this frame.
|
|
}
|
|
|
|
MOZ_ASSERT_IF(decoder->IsFirstFrameDecode(), decoder->mNumFrames == 0);
|
|
|
|
while (pass > decoder->mPass) {
|
|
// Advance to the next pass. We may have to do this multiple times because
|
|
// libpng will skip passes if the image is so small that no pixels have
|
|
// changed on a given pass, but ADAM7InterpolatingFilter needs to be reset
|
|
// once for every pass to perform interpolation properly.
|
|
decoder->mPipe.ResetToFirstRow();
|
|
decoder->mPass++;
|
|
}
|
|
|
|
const png_uint_32 height =
|
|
static_cast<png_uint_32>(decoder->mFrameRect.Height());
|
|
|
|
if (row_num >= height) {
|
|
// Bail if we receive extra rows. This is especially important because if we
|
|
// didn't, we might overflow the deinterlacing buffer.
|
|
MOZ_ASSERT_UNREACHABLE("libpng producing extra rows?");
|
|
return;
|
|
}
|
|
|
|
// Note that |new_row| may be null here, indicating that this is an interlaced
|
|
// image and |row_callback| is being called for a row that hasn't changed.
|
|
MOZ_ASSERT_IF(!new_row, decoder->interlacebuf);
|
|
uint8_t* rowToWrite = new_row;
|
|
|
|
if (decoder->interlacebuf) {
|
|
uint32_t width = uint32_t(decoder->mFrameRect.Width());
|
|
|
|
// We'll output the deinterlaced version of the row.
|
|
rowToWrite = decoder->interlacebuf + (row_num * decoder->mChannels * width);
|
|
|
|
// Update the deinterlaced version of this row with the new data.
|
|
png_progressive_combine_row(png_ptr, rowToWrite, new_row);
|
|
}
|
|
|
|
decoder->WriteRow(rowToWrite);
|
|
}
|
|
|
|
void
|
|
nsPNGDecoder::WriteRow(uint8_t* aRow)
|
|
{
|
|
MOZ_ASSERT(aRow);
|
|
|
|
uint8_t* rowToWrite = aRow;
|
|
uint32_t width = uint32_t(mFrameRect.Width());
|
|
|
|
// Apply color management to the row, if necessary, before writing it out.
|
|
if (mTransform) {
|
|
if (mCMSLine) {
|
|
qcms_transform_data(mTransform, rowToWrite, mCMSLine, width);
|
|
|
|
// Copy alpha over.
|
|
if (HasAlphaChannel()) {
|
|
for (uint32_t i = 0; i < width; ++i) {
|
|
mCMSLine[4 * i + 3] = rowToWrite[mChannels * i + mChannels - 1];
|
|
}
|
|
}
|
|
|
|
rowToWrite = mCMSLine;
|
|
} else {
|
|
qcms_transform_data(mTransform, rowToWrite, rowToWrite, width);
|
|
}
|
|
}
|
|
|
|
// Write this row to the SurfacePipe.
|
|
DebugOnly<WriteState> result;
|
|
if (HasAlphaChannel()) {
|
|
if (mDisablePremultipliedAlpha) {
|
|
result = mPipe.WritePixelsToRow<uint32_t>([&]{
|
|
return PackUnpremultipliedRGBAPixelAndAdvance(rowToWrite);
|
|
});
|
|
} else {
|
|
result = mPipe.WritePixelsToRow<uint32_t>([&]{
|
|
return PackRGBAPixelAndAdvance(rowToWrite);
|
|
});
|
|
}
|
|
} else {
|
|
result = mPipe.WritePixelsToRow<uint32_t>([&]{
|
|
return PackRGBPixelAndAdvance(rowToWrite);
|
|
});
|
|
}
|
|
|
|
MOZ_ASSERT(WriteState(result) != WriteState::FAILURE);
|
|
|
|
PostInvalidationIfNeeded();
|
|
}
|
|
|
|
void
|
|
nsPNGDecoder::DoTerminate(png_structp aPNGStruct, TerminalState aState)
|
|
{
|
|
// Stop processing data. Note that we intentionally ignore the return value of
|
|
// png_process_data_pause(), which tells us how many bytes of the data that
|
|
// was passed to png_process_data() have not been consumed yet, because now
|
|
// that we've reached a terminal state, we won't do any more decoding or call
|
|
// back into libpng anymore.
|
|
png_process_data_pause(aPNGStruct, /* save = */ false);
|
|
|
|
mNextTransition = aState == TerminalState::SUCCESS
|
|
? Transition::TerminateSuccess()
|
|
: Transition::TerminateFailure();
|
|
}
|
|
|
|
void
|
|
nsPNGDecoder::DoYield(png_structp aPNGStruct)
|
|
{
|
|
// Pause data processing. png_process_data_pause() returns how many bytes of
|
|
// the data that was passed to png_process_data() have not been consumed yet.
|
|
// We use this information to tell StreamingLexer where to place us in the
|
|
// input stream when we come back from the yield.
|
|
png_size_t pendingBytes = png_process_data_pause(aPNGStruct,
|
|
/* save = */ false);
|
|
|
|
MOZ_ASSERT(pendingBytes < mLastChunkLength);
|
|
size_t consumedBytes = mLastChunkLength - min(pendingBytes, mLastChunkLength);
|
|
|
|
mNextTransition =
|
|
Transition::ContinueUnbufferedAfterYield(State::PNG_DATA, consumedBytes);
|
|
}
|
|
|
|
nsresult
|
|
nsPNGDecoder::FinishInternal()
|
|
{
|
|
// We shouldn't be called in error cases.
|
|
MOZ_ASSERT(!HasError(), "Can't call FinishInternal on error!");
|
|
|
|
if (IsMetadataDecode()) {
|
|
return NS_OK;
|
|
}
|
|
|
|
int32_t loop_count = 0;
|
|
#ifdef PNG_APNG_SUPPORTED
|
|
if (png_get_valid(mPNG, mInfo, PNG_INFO_acTL)) {
|
|
int32_t num_plays = png_get_num_plays(mPNG, mInfo);
|
|
loop_count = num_plays - 1;
|
|
}
|
|
#endif
|
|
|
|
if (InFrame()) {
|
|
EndImageFrame();
|
|
}
|
|
PostDecodeDone(loop_count);
|
|
|
|
return NS_OK;
|
|
}
|
|
|
|
|
|
#ifdef PNG_APNG_SUPPORTED
|
|
// got the header of a new frame that's coming
|
|
void
|
|
nsPNGDecoder::frame_info_callback(png_structp png_ptr, png_uint_32 frame_num)
|
|
{
|
|
nsPNGDecoder* decoder =
|
|
static_cast<nsPNGDecoder*>(png_get_progressive_ptr(png_ptr));
|
|
|
|
// old frame is done
|
|
decoder->EndImageFrame();
|
|
|
|
const bool previousFrameWasHidden = decoder->mFrameIsHidden;
|
|
|
|
if (!previousFrameWasHidden && decoder->IsFirstFrameDecode()) {
|
|
// We're about to get a second non-hidden frame, but we only want the first.
|
|
// Stop decoding now. (And avoid allocating the unnecessary buffers below.)
|
|
return decoder->DoTerminate(png_ptr, TerminalState::SUCCESS);
|
|
}
|
|
|
|
// Only the first frame can be hidden, so unhide unconditionally here.
|
|
decoder->mFrameIsHidden = false;
|
|
|
|
// Save the information necessary to create the frame; we'll actually create
|
|
// it when we return from the yield.
|
|
const IntRect frameRect(png_get_next_frame_x_offset(png_ptr, decoder->mInfo),
|
|
png_get_next_frame_y_offset(png_ptr, decoder->mInfo),
|
|
png_get_next_frame_width(png_ptr, decoder->mInfo),
|
|
png_get_next_frame_height(png_ptr, decoder->mInfo));
|
|
const bool isInterlaced = bool(decoder->interlacebuf);
|
|
|
|
#ifndef MOZ_EMBEDDED_LIBPNG
|
|
// if using system library, check frame_width and height against 0
|
|
if (frameRect.width == 0) {
|
|
png_error(png_ptr, "Frame width must not be 0");
|
|
}
|
|
if (frameRect.height == 0) {
|
|
png_error(png_ptr, "Frame height must not be 0");
|
|
}
|
|
#endif
|
|
|
|
const FrameInfo info { frameRect, isInterlaced };
|
|
|
|
// If the previous frame was hidden, skip the yield (which will mislead the
|
|
// caller, who will think the previous frame was real) and just allocate the
|
|
// new frame here.
|
|
if (previousFrameWasHidden) {
|
|
if (NS_FAILED(decoder->CreateFrame(info))) {
|
|
return decoder->DoTerminate(png_ptr, TerminalState::FAILURE);
|
|
}
|
|
|
|
MOZ_ASSERT(decoder->mImageData, "Should have a buffer now");
|
|
return; // No yield, so we'll just keep decoding.
|
|
}
|
|
|
|
// Yield to the caller to notify them that the previous frame is now complete.
|
|
decoder->mNextFrameInfo = Some(info);
|
|
return decoder->DoYield(png_ptr);
|
|
}
|
|
#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
|
|
MOZ_ASSERT(!decoder->HasError(), "Finishing up PNG but hit error!");
|
|
|
|
return decoder->DoTerminate(png_ptr, TerminalState::SUCCESS);
|
|
}
|
|
|
|
|
|
void
|
|
nsPNGDecoder::error_callback(png_structp png_ptr, png_const_charp error_msg)
|
|
{
|
|
MOZ_LOG(sPNGLog, LogLevel::Error, ("libpng error: %s\n", error_msg));
|
|
png_longjmp(png_ptr, 1);
|
|
}
|
|
|
|
|
|
void
|
|
nsPNGDecoder::warning_callback(png_structp png_ptr, png_const_charp warning_msg)
|
|
{
|
|
MOZ_LOG(sPNGLog, LogLevel::Warning, ("libpng warning: %s\n", warning_msg));
|
|
}
|
|
|
|
Maybe<Telemetry::HistogramID>
|
|
nsPNGDecoder::SpeedHistogram() const
|
|
{
|
|
return Some(Telemetry::IMAGE_DECODE_SPEED_PNG);
|
|
}
|
|
|
|
bool
|
|
nsPNGDecoder::IsValidICOResource() const
|
|
{
|
|
// Only 32-bit RGBA PNGs are valid ICO resources; see here:
|
|
// http://blogs.msdn.com/b/oldnewthing/archive/2010/10/22/10079192.aspx
|
|
|
|
// If there are errors in the call to png_get_IHDR, the error_callback in
|
|
// nsPNGDecoder.cpp is called. In this error callback we do a longjmp, so
|
|
// we need to save the jump buffer here. Otherwise we'll end up without a
|
|
// proper callstack.
|
|
if (setjmp(png_jmpbuf(mPNG))) {
|
|
// We got here from a longjmp call indirectly from png_get_IHDR
|
|
return false;
|
|
}
|
|
|
|
png_uint_32
|
|
png_width, // Unused
|
|
png_height; // Unused
|
|
|
|
int png_bit_depth,
|
|
png_color_type;
|
|
|
|
if (png_get_IHDR(mPNG, mInfo, &png_width, &png_height, &png_bit_depth,
|
|
&png_color_type, nullptr, nullptr, nullptr)) {
|
|
|
|
return ((png_color_type == PNG_COLOR_TYPE_RGB_ALPHA ||
|
|
png_color_type == PNG_COLOR_TYPE_RGB) &&
|
|
png_bit_depth == 8);
|
|
} else {
|
|
return false;
|
|
}
|
|
}
|
|
|
|
} // namespace image
|
|
} // namespace mozilla
|