DeferredImageDecoder: early-out onGetYUV8Planes when possible

third_party/WebKit/Source/platform/graphics/DeferredImageDecoder.cpp

 /*
  * Copyright (C) 2012 Google 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 "config.h"
 #include "platform/graphics/DeferredImageDecoder.h"
 
+#include "platform/RuntimeEnabledFeatures.h"
 #include "platform/graphics/DecodingImageGenerator.h"
 #include "platform/graphics/FrameData.h"
 #include "platform/graphics/ImageDecodingStore.h"
 #include "platform/graphics/ImageFrameGenerator.h"
 #include "third_party/skia/include/core/SkImage.h"
 #include "wtf/PassOwnPtr.h"
 
 namespace blink {
 
 bool DeferredImageDecoder::s_enabled = true;
@@ skipping 12 matching lines @@
 {
     return adoptPtr(new DeferredImageDecoder(actualDecoder));
 }
 
 DeferredImageDecoder::DeferredImageDecoder(PassOwnPtr<ImageDecoder> actualDecoder)
     : m_allDataReceived(false)
     , m_lastDataSize(0)
     , m_actualDecoder(actualDecoder)
     , m_repetitionCount(cAnimationNone)
     , m_hasColorProfile(false)
+    , m_canYUVDecode(false)
 {
 }
 
 DeferredImageDecoder::~DeferredImageDecoder()
 {
 }
 
 void DeferredImageDecoder::setEnabled(bool enabled)
 {
     s_enabled = enabled;
@@ skipping 136 matching lines @@
         return m_actualDecoder->orientation();
     if (index < m_frameData.size())
         return m_frameData[index].m_orientation;
     return DefaultImageOrientation;
 }
 
 void DeferredImageDecoder::activateLazyDecoding()
 {
     if (m_frameGenerator)
         return;
+
     m_size = m_actualDecoder->size();
     m_filenameExtension = m_actualDecoder->filenameExtension();
+    // JPEG images support YUV decoding: other decoders do not, WEBP could in future.
+    m_canYUVDecode = RuntimeEnabledFeatures::decodeToYUVEnabled() && (m_filenameExtension == "jpg");
     m_hasColorProfile = m_actualDecoder->hasColorProfile();
+
     const bool isSingleFrame = m_actualDecoder->repetitionCount() == cAnimationNone || (m_allDataReceived && m_actualDecoder->frameCount() == 1u);
     m_frameGenerator = ImageFrameGenerator::create(SkISize::Make(m_actualDecoder->decodedSize().width(), m_actualDecoder->decodedSize().height()), m_data, m_allDataReceived, !isSingleFrame);
 }
 
 void DeferredImageDecoder::prepareLazyDecodedFrames()
 {
     if (!s_enabled
         || !m_actualDecoder
         || !m_actualDecoder->isSizeAvailable()
         || m_actualDecoder->filenameExtension() == "ico")
@@ skipping 34 matching lines @@
     return SkImageInfo::MakeN32(decodedSize.width(), decodedSize.height(), knownToBeOpaque ? kOpaque_SkAlphaType : kPremul_SkAlphaType);
 }
 
 PassRefPtr<SkImage> DeferredImageDecoder::createFrameImageAtIndex(size_t index, bool knownToBeOpaque) const
 {
     const SkISize& decodedSize = m_frameGenerator->getFullSize();
     ASSERT(decodedSize.width() > 0);
     ASSERT(decodedSize.height() > 0);
 
     DecodingImageGenerator* generator = new DecodingImageGenerator(m_frameGenerator, imageInfoFrom(decodedSize, knownToBeOpaque), index);
-    RefPtr<SkImage> image = adoptRef(SkImage::NewFromGenerator(generator));
+    RefPtr<SkImage> image = adoptRef(SkImage::NewFromGenerator(generator)); // SkImage takes ownership of the generator.
     if (!image)
         return nullptr;
 
     generator->setGenerationId(image->uniqueID());
+    generator->setCanYUVDecode(m_canYUVDecode);
+
     return image.release();
 }
 
 bool DeferredImageDecoder::hotSpot(IntPoint& hotSpot) const
 {
     // TODO: Implement.
     return m_actualDecoder ? m_actualDecoder->hotSpot(hotSpot) : false;
 }
 
 } // namespace blink