Move gif image decoder to SkCodec

third_party/WebKit/Source/platform/image-decoders/gif/GIFImageDecoder.cpp

 /*
  * Copyright (C) 2006 Apple Computer, Inc.  All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  *
  * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include "platform/image-decoders/gif/GIFImageDecoder.h"
 
-#include "platform/image-decoders/gif/GIFImageReader.h"
+#include "base/logging.h"
+#include "third_party/skia/include/core/SkImageInfo.h"
 #include "wtf/NotFound.h"
 #include "wtf/PtrUtil.h"
 #include <limits>
 
 namespace blink {
 
 GIFImageDecoder::GIFImageDecoder(AlphaOption alphaOption,
                                  ColorSpaceOption colorOptions,
                                  sk_sp<SkColorSpace> targetColorSpace,
                                  size_t maxDecodedBytes)
     : ImageDecoder(alphaOption,
                    colorOptions,
                    std::move(targetColorSpace),
                    maxDecodedBytes),
-      m_repetitionCount(cAnimationLoopOnce) {}
+      m_codec(),
+      m_segmentStream(nullptr) {}
 
-GIFImageDecoder::~GIFImageDecoder() {}
+GIFImageDecoder::~GIFImageDecoder() {
+  if (!m_codec) {
+    // if we did not create m_codec and thus did not pass ownership to it
+    if (m_segmentStream) {
+      delete m_segmentStream;
+    }
+  }
+}
 
 void GIFImageDecoder::onSetData(SegmentReader* data) {
-  if (m_reader)
-    m_reader->setData(data);
+  // Add the segment to our stream
+  if (!m_segmentStream) {
+    m_segmentStream = new SegmentStream();
+  }
+
+  m_segmentStream->setReader(data, isAllDataReceived());
+
+  // If we don't have a SkCodec yet, create one from the stream
+  if (!m_codec) {
+    SkCodec* newCodec = SkCodec::NewFromStream(m_segmentStream);
+    if (newCodec) {
+      m_codec.reset(newCodec);
+    }
+  }
 }
 
 int GIFImageDecoder::repetitionCount() const {
+  CHECK(m_codec);
+
   // This value can arrive at any point in the image data stream.  Most GIFs
   // in the wild declare it near the beginning of the file, so it usually is
   // set by the time we've decoded the size, but (depending on the GIF and the
-  // packets sent back by the webserver) not always.  If the reader hasn't
-  // seen a loop count yet, it will return cLoopCountNotSeen, in which case we
-  // should default to looping once (the initial value for
-  // |m_repetitionCount|).
+  // packets sent back by the webserver) not always.
   //
-  // There are some additional wrinkles here. First, ImageSource::clear()
-  // may destroy the reader, making the result from the reader _less_
-  // authoritative on future calls if the recreated reader hasn't seen the
-  // loop count.  We don't need to special-case this because in this case the
-  // new reader will once again return cLoopCountNotSeen, and we won't
-  // overwrite the cached correct value.
-  //
-  // Second, a GIF might never set a loop count at all, in which case we
-  // should continue to treat it as a "loop once" animation.  We don't need
-  // special code here either, because in this case we'll never change
-  // |m_repetitionCount| from its default value.
-  //
-  // Third, we use the same GIFImageReader for counting frames and we might
-  // see the loop count and then encounter a decoding error which happens
-  // later in the stream. It is also possible that no frames are in the
-  // stream. In these cases we should just loop once.
-  if (isAllDataReceived() && parseCompleted() && m_reader->imagesCount() == 1)
-    m_repetitionCount = cAnimationNone;
-  else if (failed() || (m_reader && (!m_reader->imagesCount())))
-    m_repetitionCount = cAnimationLoopOnce;
-  else if (m_reader && m_reader->loopCount() != cLoopCountNotSeen)
-    m_repetitionCount = m_reader->loopCount();
-  return m_repetitionCount;
+  // SkCodec will parse forward in the file if the repetition count has not been
+  // seen yet.
+
+  int repetitionCount = m_codec->getRepetitionCount();
+  switch (repetitionCount) {
+    case 0:
+      return cAnimationNone;
+    case SkCodec::kRepetitionCountInfinite:
+      return cAnimationLoopInfinite;
+    default:
+      return repetitionCount;
+  }
 }
 
 bool GIFImageDecoder::frameIsCompleteAtIndex(size_t index) const {
-  return m_reader && (index < m_reader->imagesCount()) &&
-         m_reader->frameContext(index)->isComplete();
+  CHECK(m_codec);
+
+  std::vector<SkCodec::FrameInfo> frameInfos = m_codec->getFrameInfo();
+
+  // If https://skia-review.googlesource.com/c/5635/ lands
+  if (index == 0) {
+    return (frameInfos.size() > 1 || isAllDataReceived());
+    // Either We have found a second frame, which means frame 0 is complete,
+    // or we have all the data, the image could be a single-frame and complete.
+  }
+
+  return frameInfos.size() > index;
+
+  // If https://skia-review.googlesource.com/c/5703/ lands:
+  // if (frameInfos.size() < index) {
+  // // index out of bounds as far as we have parsed
+  // return false;
+  //}
+  //
+  // return frameInfos[index].fFullyReceived;
 }
 
 float GIFImageDecoder::frameDurationAtIndex(size_t index) const {
-  return (m_reader && (index < m_reader->imagesCount()) &&
-          m_reader->frameContext(index)->isHeaderDefined())
-             ? m_reader->frameContext(index)->delayTime()
-             : 0;
+  CHECK(m_codec);
+
+  std::vector<SkCodec::FrameInfo> frameInfos = m_codec->getFrameInfo();
+
+  if (frameInfos.size() < index) {
+    // index out of bounds as far as we have parsed
+    return 0;
+  }
+
+  return frameInfos[index].fDuration;
 }
 
-bool GIFImageDecoder::setFailed() {
-  m_reader.reset();
-  return ImageDecoder::setFailed();
+void GIFImageDecoder::decodeSize() {
+  CHECK(m_codec);
+
+  SkImageInfo imageInfo = m_codec->getInfo();
+  setSize(imageInfo.width(), imageInfo.height());
 }
 
-bool GIFImageDecoder::haveDecodedRow(size_t frameIndex,
-                                     GIFRow::const_iterator rowBegin,
-                                     size_t width,
-                                     size_t rowNumber,
-                                     unsigned repeatCount,
-                                     bool writeTransparentPixels) {
-  const GIFFrameContext* frameContext = m_reader->frameContext(frameIndex);
-  // The pixel data and coordinates supplied to us are relative to the frame's
-  // origin within the entire image size, i.e.
-  // (frameContext->xOffset, frameContext->yOffset). There is no guarantee
-  // that width == (size().width() - frameContext->xOffset), so
-  // we must ensure we don't run off the end of either the source data or the
-  // row's X-coordinates.
-  const int xBegin = frameContext->xOffset();
-  const int yBegin = frameContext->yOffset() + rowNumber;
-  const int xEnd = std::min(static_cast<int>(frameContext->xOffset() + width),
-                            size().width());
-  const int yEnd = std::min(
-      static_cast<int>(frameContext->yOffset() + rowNumber + repeatCount),
-      size().height());
-  if (!width || (xBegin < 0) || (yBegin < 0) || (xEnd <= xBegin) ||
-      (yEnd <= yBegin))
-    return true;
+size_t GIFImageDecoder::decodeFrameCount() {
+  std::vector<SkCodec::FrameInfo> frameInfos = m_codec->getFrameInfo();
+  return frameInfos.size();
+}
 
-  const GIFColorMap::Table& colorTable =
-      frameContext->localColorMap().isDefined()
-          ? frameContext->localColorMap().getTable()
-          : m_reader->globalColorMap().getTable();
+void GIFImageDecoder::initializeNewFrame(size_t index) {
+  CHECK(m_codec);
 
-  if (colorTable.isEmpty())
-    return true;
+  ImageFrame& frame = m_frameBufferCache[index];
+  std::vector<SkCodec::FrameInfo> frameInfos = m_codec->getFrameInfo();
 
-  GIFColorMap::Table::const_iterator colorTableIter = colorTable.begin();
+  frame.setOriginalFrameRect(IntRect(IntPoint(), size()));
+  frame.setDuration(frameInfos[index].fDuration);
+  frame.setDisposalMethod(ImageFrame::DisposeKeep);
+  size_t requiredPreviousFrame = frameInfos[index].fRequiredFrame;
+  if (requiredPreviousFrame == SkCodec::kNone) {
+    requiredPreviousFrame = WTF::kNotFound;
+  }
+  frame.setRequiredPreviousFrameIndex(requiredPreviousFrame);
+}
 
-  // Initialize the frame if necessary.
-  ImageFrame& buffer = m_frameBufferCache[frameIndex];
-  if (!initFrameBuffer(frameIndex))
-    return false;
+void GIFImageDecoder::decode(size_t index) {
+  CHECK(m_codec);
 
-  const size_t transparentPixel = frameContext->transparentPixel();
-  GIFRow::const_iterator rowEnd = rowBegin + (xEnd - xBegin);
-  ImageFrame::PixelData* currentAddress = buffer.getAddr(xBegin, yBegin);
+  if (m_frameBufferCache.size() < index) {

[scroggo_chromium, 2016/12/14 17:49:23]

<=

[cblume, 2016/12/16 02:57:10]

Done.

+    // index out of bounds as far as we have parsed
+    return;
+  }
 
-  // We may or may not need to write transparent pixels to the buffer.
-  // If we're compositing against a previous image, it's wrong, and if
-  // we're writing atop a cleared, fully transparent buffer, it's
-  // unnecessary; but if we're decoding an interlaced gif and
-  // displaying it "Haeberli"-style, we must write these for passes
-  // beyond the first, or the initial passes will "show through" the
-  // later ones.
-  //
-  // The loops below are almost identical. One writes a transparent pixel
-  // and one doesn't based on the value of |writeTransparentPixels|.
-  // The condition check is taken out of the loop to enhance performance.
-  // This optimization reduces decoding time by about 15% for a 3MB image.
-  if (writeTransparentPixels) {
-    for (; rowBegin != rowEnd; ++rowBegin, ++currentAddress) {
-      const size_t sourceValue = *rowBegin;
-      if ((sourceValue != transparentPixel) &&
-          (sourceValue < colorTable.size())) {
-        *currentAddress = colorTableIter[sourceValue];
-      } else {
-        *currentAddress = 0;
-        m_currentBufferSawAlpha = true;
-      }
-    }
-  } else {
-    for (; rowBegin != rowEnd; ++rowBegin, ++currentAddress) {
-      const size_t sourceValue = *rowBegin;
-      if ((sourceValue != transparentPixel) &&
-          (sourceValue < colorTable.size()))
-        *currentAddress = colorTableIter[sourceValue];
-      else
-        m_currentBufferSawAlpha = true;
+  updateAggressivePurging(index);
+
+  SkImageInfo imageInfo = m_codec->getInfo().makeColorType(kN32_SkColorType);
+  // Index8 has special behavior when getting the pixels, which we do not yet

[scroggo_chromium, 2016/12/14 17:49:23]

This comment can be removed.

[cblume, 2016/12/16 02:57:10]

Done.

+  // handle
+
+  SkCodec::Options getPixelsOptions;
+  getPixelsOptions.fFrameIndex = index;
+  getPixelsOptions.fHasPriorFrame = false;
+
+  ImageFrame& frame = m_frameBufferCache[index];
+  if (frame.getStatus() != ImageFrame::FrameComplete) {
+    size_t requiredPreviousFrameIndex = frame.requiredPreviousFrameIndex();
+    if (requiredPreviousFrameIndex != WTF::kNotFound) {
+      getPixelsOptions.fHasPriorFrame = true;
     }
   }
 
-  // Tell the frame to copy the row data if need be.
-  if (repeatCount > 1)
-    buffer.copyRowNTimes(xBegin, xEnd, yBegin, yEnd);
-
-  buffer.setPixelsChanged(true);
-  return true;
-}
-
-bool GIFImageDecoder::parseCompleted() const {
-  return m_reader && m_reader->parseCompleted();
-}
-
-bool GIFImageDecoder::frameComplete(size_t frameIndex) {
-  // Initialize the frame if necessary.  Some GIFs insert do-nothing frames,
-  // in which case we never reach haveDecodedRow() before getting here.
-  ImageFrame& buffer = m_frameBufferCache[frameIndex];
-  if (!initFrameBuffer(frameIndex))
-    return false;  // initFrameBuffer() has already called setFailed().
-
-  buffer.setStatus(ImageFrame::FrameComplete);
-
-  if (!m_currentBufferSawAlpha) {
-    // The whole frame was non-transparent, so it's possible that the entire
-    // resulting buffer was non-transparent, and we can setHasAlpha(false).
-    if (buffer.originalFrameRect().contains(IntRect(IntPoint(), size()))) {
-      buffer.setHasAlpha(false);
-      buffer.setRequiredPreviousFrameIndex(kNotFound);
-    } else if (buffer.requiredPreviousFrameIndex() != kNotFound) {
-      // Tricky case.  This frame does not have alpha only if everywhere
-      // outside its rect doesn't have alpha.  To know whether this is
-      // true, we check the start state of the frame -- if it doesn't have
-      // alpha, we're safe.
-      const ImageFrame* prevBuffer =
-          &m_frameBufferCache[buffer.requiredPreviousFrameIndex()];
-      ASSERT(prevBuffer->getDisposalMethod() !=
-             ImageFrame::DisposeOverwritePrevious);
-
-      // Now, if we're at a DisposeNotSpecified or DisposeKeep frame, then
-      // we can say we have no alpha if that frame had no alpha.  But
-      // since in initFrameBuffer() we already copied that frame's alpha
-      // state into the current frame's, we need do nothing at all here.
-      //
-      // The only remaining case is a DisposeOverwriteBgcolor frame.  If
-      // it had no alpha, and its rect is contained in the current frame's
-      // rect, we know the current frame has no alpha.
-      if ((prevBuffer->getDisposalMethod() ==
-           ImageFrame::DisposeOverwriteBgcolor) &&
-          !prevBuffer->hasAlpha() &&
-          buffer.originalFrameRect().contains(prevBuffer->originalFrameRect()))
-        buffer.setHasAlpha(false);
-    }
+  SkCodec::Result getPixelsResult =
+      m_codec->getPixels(imageInfo, frame.bitmap().getPixels(),
+                         frame.bitmap().rowBytes(),
+                         &getPixelsOptions, nullptr, nullptr);
+  if (getPixelsResult != SkCodec::kSuccess &&
+      getPixelsResult != SkCodec::kIncompleteInput) {
+    setFailed();
+    return;
   }
 
-  return true;
-}
+  if (!postDecodeProcessing(index)) {
+    return;
+  }
 
-void GIFImageDecoder::clearFrameBuffer(size_t frameIndex) {
-  if (m_reader &&
-      m_frameBufferCache[frameIndex].getStatus() == ImageFrame::FramePartial) {
-    // Reset the state of the partial frame in the reader so that the frame
-    // can be decoded again when requested.
-    m_reader->clearDecodeState(frameIndex);
-  }
-  ImageDecoder::clearFrameBuffer(frameIndex);
-}
-
-size_t GIFImageDecoder::decodeFrameCount() {
-  parse(GIFFrameCountQuery);
-  // If decoding fails, |m_reader| will have been destroyed.  Instead of
-  // returning 0 in this case, return the existing number of frames.  This way
-  // if we get halfway through the image before decoding fails, we won't
-  // suddenly start reporting that the image has zero frames.
-  return failed() ? m_frameBufferCache.size() : m_reader->imagesCount();
-}
-
-void GIFImageDecoder::initializeNewFrame(size_t index) {
-  ImageFrame* buffer = &m_frameBufferCache[index];
-  const GIFFrameContext* frameContext = m_reader->frameContext(index);
-  buffer->setOriginalFrameRect(
-      intersection(frameContext->frameRect(), IntRect(IntPoint(), size())));
-  buffer->setDuration(frameContext->delayTime());
-  buffer->setDisposalMethod(frameContext->getDisposalMethod());
-  buffer->setRequiredPreviousFrameIndex(
-      findRequiredPreviousFrame(index, false));
-}
-
-void GIFImageDecoder::decode(size_t index) {
-  parse(GIFFrameCountQuery);
-
-  if (failed())
-    return;
-
-  updateAggressivePurging(index);
-
-  Vector<size_t> framesToDecode = findFramesToDecode(index);
-  for (auto i = framesToDecode.rbegin(); i != framesToDecode.rend(); ++i) {
-    if (!m_reader->decode(*i)) {
-      setFailed();
-      return;
-    }
-
-    // If this returns false, we need more data to continue decoding.
-    if (!postDecodeProcessing(*i))
-      break;
-  }
+  // If we do not end up landing https://skia-review.googlesource.com/c/5635/
+  // ...
 
   // It is also a fatal error if all data is received and we have decoded all
   // frames available but the file is truncated.
-  if (index >= m_frameBufferCache.size() - 1 && isAllDataReceived() &&
-      m_reader && !m_reader->parseCompleted())
+  if (index >= m_frameBufferCache.size() - 1 && isAllDataReceived()) {
     setFailed();
-}
-
-void GIFImageDecoder::parse(GIFParseQuery query) {
-  if (failed())
-    return;
-
-  if (!m_reader) {
-    m_reader = makeUnique<GIFImageReader>(this);
-    m_reader->setData(m_data);
   }
-
-  if (!m_reader->parse(query))
-    setFailed();
-}
-
-void GIFImageDecoder::onInitFrameBuffer(size_t frameIndex) {
-  m_currentBufferSawAlpha = false;
 }
 
 bool GIFImageDecoder::canReusePreviousFrameBuffer(size_t frameIndex) const {
   DCHECK(frameIndex < m_frameBufferCache.size());
   return m_frameBufferCache[frameIndex].getDisposalMethod() !=
          ImageFrame::DisposeOverwritePrevious;
 }
 
 }  // namespace blink