[WIP] Move ImageDecoders to SkCodec

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

Index: third_party/WebKit/Source/platform/image-decoders/gif/GIFImageDecoder.cpp
diff --git a/third_party/WebKit/Source/platform/image-decoders/gif/GIFImageDecoder.cpp b/third_party/WebKit/Source/platform/image-decoders/gif/GIFImageDecoder.cpp
deleted file mode 100644
index b954a982e6fbc2decfe0c22117ab6573de011dc8..0000000000000000000000000000000000000000
--- a/third_party/WebKit/Source/platform/image-decoders/gif/GIFImageDecoder.cpp
+++ /dev/null
@@ -1,282 +0,0 @@
-/*
- * 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 <limits>
-#include "platform/image-decoders/gif/GIFImageReader.h"
-#include "platform/wtf/NotFound.h"
-#include "platform/wtf/PtrUtil.h"
-
-namespace blink {
-
-GIFImageDecoder::GIFImageDecoder(AlphaOption alpha_option,
-                                 const ColorBehavior& color_behavior,
-                                 size_t max_decoded_bytes)
-    : ImageDecoder(alpha_option, color_behavior, max_decoded_bytes),
-      repetition_count_(kAnimationLoopOnce) {}
-
-GIFImageDecoder::~GIFImageDecoder() {}
-
-void GIFImageDecoder::OnSetData(SegmentReader* data) {
-  if (reader_)
-    reader_->SetData(data);
-}
-
-int GIFImageDecoder::RepetitionCount() const {
-  // 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 kCLoopCountNotSeen, in which case we
-  // should default to looping once (the initial value for
-  // |repetition_count_|).
-  //
-  // 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 kCLoopCountNotSeen, 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
-  // |repetition_count_| 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() && reader_->ImagesCount() == 1)
-    repetition_count_ = kAnimationNone;
-  else if (Failed() || (reader_ && (!reader_->ImagesCount())))
-    repetition_count_ = kAnimationLoopOnce;
-  else if (reader_ && reader_->LoopCount() != kCLoopCountNotSeen)
-    repetition_count_ = reader_->LoopCount();
-  return repetition_count_;
-}
-
-bool GIFImageDecoder::FrameIsCompleteAtIndex(size_t index) const {
-  return reader_ && (index < reader_->ImagesCount()) &&
-         reader_->FrameContext(index)->IsComplete();
-}
-
-float GIFImageDecoder::FrameDurationAtIndex(size_t index) const {
-  return (reader_ && (index < reader_->ImagesCount()) &&
-          reader_->FrameContext(index)->IsHeaderDefined())
-             ? reader_->FrameContext(index)->DelayTime()
-             : 0;
-}
-
-bool GIFImageDecoder::SetFailed() {
-  reader_.reset();
-  return ImageDecoder::SetFailed();
-}
-
-bool GIFImageDecoder::HaveDecodedRow(size_t frame_index,
-                                     GIFRow::const_iterator row_begin,
-                                     size_t width,
-                                     size_t row_number,
-                                     unsigned repeat_count,
-                                     bool write_transparent_pixels) {
-  const GIFFrameContext* frame_context = reader_->FrameContext(frame_index);
-  // The pixel data and coordinates supplied to us are relative to the frame's
-  // origin within the entire image size, i.e.
-  // (frameC_context->xOffset, frame_context->yOffset). There is no guarantee
-  // that width == (size().width() - frame_context->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 x_begin = frame_context->XOffset();
-  const int y_begin = frame_context->YOffset() + row_number;
-  const int x_end = std::min(static_cast<int>(frame_context->XOffset() + width),
-                             Size().Width());
-  const int y_end = std::min(
-      static_cast<int>(frame_context->YOffset() + row_number + repeat_count),
-      Size().Height());
-  if (!width || (x_begin < 0) || (y_begin < 0) || (x_end <= x_begin) ||
-      (y_end <= y_begin))
-    return true;
-
-  const GIFColorMap::Table& color_table =
-      frame_context->LocalColorMap().IsDefined()
-          ? frame_context->LocalColorMap().GetTable()
-          : reader_->GlobalColorMap().GetTable();
-
-  if (color_table.IsEmpty())
-    return true;
-
-  GIFColorMap::Table::const_iterator color_table_iter = color_table.begin();
-
-  // Initialize the frame if necessary.
-  ImageFrame& buffer = frame_buffer_cache_[frame_index];
-  if (!InitFrameBuffer(frame_index))
-    return false;
-
-  const size_t transparent_pixel = frame_context->TransparentPixel();
-  GIFRow::const_iterator row_end = row_begin + (x_end - x_begin);
-  ImageFrame::PixelData* current_address = buffer.GetAddr(x_begin, y_begin);
-
-  // 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 |write_transparent_pixels|.
-  // 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 (write_transparent_pixels) {
-    for (; row_begin != row_end; ++row_begin, ++current_address) {
-      const size_t source_value = *row_begin;
-      if ((source_value != transparent_pixel) &&
-          (source_value < color_table.size())) {
-        *current_address = color_table_iter[source_value];
-      } else {
-        *current_address = 0;
-        current_buffer_saw_alpha_ = true;
-      }
-    }
-  } else {
-    for (; row_begin != row_end; ++row_begin, ++current_address) {
-      const size_t source_value = *row_begin;
-      if ((source_value != transparent_pixel) &&
-          (source_value < color_table.size()))
-        *current_address = color_table_iter[source_value];
-      else
-        current_buffer_saw_alpha_ = true;
-    }
-  }
-
-  // Tell the frame to copy the row data if need be.
-  if (repeat_count > 1)
-    buffer.CopyRowNTimes(x_begin, x_end, y_begin, y_end);
-
-  buffer.SetPixelsChanged(true);
-  return true;
-}
-
-bool GIFImageDecoder::ParseCompleted() const {
-  return reader_ && reader_->ParseCompleted();
-}
-
-bool GIFImageDecoder::FrameComplete(size_t frame_index) {
-  // Initialize the frame if necessary.  Some GIFs insert do-nothing frames,
-  // in which case we never reach HaveDecodedRow() before getting here.
-  if (!InitFrameBuffer(frame_index))
-    return SetFailed();
-
-  if (!current_buffer_saw_alpha_)
-    CorrectAlphaWhenFrameBufferSawNoAlpha(frame_index);
-
-  frame_buffer_cache_[frame_index].SetStatus(ImageFrame::kFrameComplete);
-
-  return true;
-}
-
-void GIFImageDecoder::ClearFrameBuffer(size_t frame_index) {
-  if (reader_ && frame_buffer_cache_[frame_index].GetStatus() ==
-                     ImageFrame::kFramePartial) {
-    // Reset the state of the partial frame in the reader so that the frame
-    // can be decoded again when requested.
-    reader_->ClearDecodeState(frame_index);
-  }
-  ImageDecoder::ClearFrameBuffer(frame_index);
-}
-
-size_t GIFImageDecoder::DecodeFrameCount() {
-  Parse(kGIFFrameCountQuery);
-  // If decoding fails, |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() ? frame_buffer_cache_.size() : reader_->ImagesCount();
-}
-
-void GIFImageDecoder::InitializeNewFrame(size_t index) {
-  ImageFrame* buffer = &frame_buffer_cache_[index];
-  const GIFFrameContext* frame_context = reader_->FrameContext(index);
-  buffer->SetOriginalFrameRect(
-      Intersection(frame_context->FrameRect(), IntRect(IntPoint(), Size())));
-  buffer->SetDuration(frame_context->DelayTime());
-  buffer->SetDisposalMethod(frame_context->GetDisposalMethod());
-  buffer->SetRequiredPreviousFrameIndex(
-      FindRequiredPreviousFrame(index, false));
-}
-
-void GIFImageDecoder::Decode(size_t index) {
-  Parse(kGIFFrameCountQuery);
-
-  if (Failed())
-    return;
-
-  UpdateAggressivePurging(index);
-
-  Vector<size_t> frames_to_decode = FindFramesToDecode(index);
-  for (auto i = frames_to_decode.rbegin(); i != frames_to_decode.rend(); ++i) {
-    if (!reader_->Decode(*i)) {
-      SetFailed();
-      return;
-    }
-
-    // If this returns false, we need more data to continue decoding.
-    if (!PostDecodeProcessing(*i))
-      break;
-  }
-
-  // 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 >= frame_buffer_cache_.size() - 1 && IsAllDataReceived() &&
-      reader_ && !reader_->ParseCompleted())
-    SetFailed();
-}
-
-void GIFImageDecoder::Parse(GIFParseQuery query) {
-  if (Failed())
-    return;
-
-  if (!reader_) {
-    reader_ = WTF::MakeUnique<GIFImageReader>(this);
-    reader_->SetData(data_);
-  }
-
-  if (!reader_->Parse(query))
-    SetFailed();
-}
-
-void GIFImageDecoder::OnInitFrameBuffer(size_t frame_index) {
-  current_buffer_saw_alpha_ = false;
-}
-
-bool GIFImageDecoder::CanReusePreviousFrameBuffer(size_t frame_index) const {
-  DCHECK(frame_index < frame_buffer_cache_.size());
-  return frame_buffer_cache_[frame_index].GetDisposalMethod() !=
-         ImageFrame::kDisposeOverwritePrevious;
-}
-
-}  // namespace blink