GIF decoding to Index8, unit tests and misusing unit test as benchmark

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

 /*
  * Copyright (C) 2013 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 14 matching lines @@
  * 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/image-decoders/gif/GIFImageDecoder.h"
 
 #include "platform/SharedBuffer.h"
+#include "platform/graphics/ImageDecodingStore.h"
+#include "platform/graphics/ImageFrameGenerator.h"
 #include "platform/image-decoders/ImageDecoderTestHelpers.h"
 #include "public/platform/WebData.h"
 #include "public/platform/WebSize.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "wtf/OwnPtr.h"
 #include "wtf/PassOwnPtr.h"
 #include "wtf/Vector.h"
 
 namespace blink {
 
 namespace {
 
 const char decodersTestingDir[] = "Source/platform/image-decoders/testing";
 const char layoutTestResourcesDir[] = "LayoutTests/fast/images/resources";
 const char webTestsDataDir[] = "Source/web/tests/data";
 
-PassOwnPtr<ImageDecoder> createDecoder()
+#define LOOP_DECODERS_BEGIN \
+    DecoderCreator decoderCreators[2] = { &createDecoderN32, &createDecoderIndex8 }; \
+    for (DecoderCreator createDecoder : decoderCreators) {
+
+#define LOOP_DECODERS_END \
+    }
+
+PassOwnPtr<ImageDecoder> createDecoderN32()
 {
-    return adoptPtr(new GIFImageDecoder(ImageDecoder::AlphaNotPremultiplied, ImageDecoder::GammaAndColorProfileApplied, ImageDecoder::noDecodedImageByteLimit));
+    return adoptPtr(new GIFImageDecoder(ImageDecoder::AlphaNotPremultiplied, ImageDecoder::GammaAndColorProfileApplied, ImageDecoder::noDecodedImageByteLimit, ImageFrame::N32));
+}
+
+PassOwnPtr<ImageDecoder> createDecoderIndex8()
+{
+    return adoptPtr(new GIFImageDecoder(ImageDecoder::AlphaNotPremultiplied, ImageDecoder::GammaAndColorProfileApplied, ImageDecoder::noDecodedImageByteLimit, ImageFrame::Index8));
+}
+
+static bool areBitmapsColorsEqual(const SkBitmap& bitmap1, const SkBitmap& bitmap2)
+{
+    int width = bitmap1.width();
+    int height = bitmap1.height();
+    int width2 = bitmap2.width();
+    int height2 = bitmap2.height();
+    if (bitmap1.alphaType() != bitmap2.alphaType())
+        return false;
+    if (bitmap1.profileType() != bitmap2.profileType())
+        return false;
+    if (width != width2 || height != height2)
+        return false;
+
+    for (int j = 0; j < height; ++j) {
+        for (int i = 0; i < width; ++i) {
+            uint32_t c1 = bitmap1.getColor(i, j);
+            uint32_t c2 = bitmap2.getColor(i, j);
+            if (c1 != c2) {
+                return false;
+            }
+        }
+    }
+
+    return true;
+}
+
+static bool areFramesColorsEqual(const ImageFrame& b1, const ImageFrame& b2)
+{
+    // The same premultiply alpha should be set.
+    if (b1.premultiplyAlpha() != b2.premultiplyAlpha())
+        return false;
+    return areBitmapsColorsEqual(b1.getSkBitmap(), b2.getSkBitmap());
 }
 
 void testRandomFrameDecode(const char* dir, const char* gifFile)
 {
+    LOOP_DECODERS_BEGIN
     SCOPED_TRACE(gifFile);
 
     RefPtr<SharedBuffer> fullData = readFile(dir, gifFile);
     ASSERT_TRUE(fullData.get());
     Vector<unsigned> baselineHashes;
-    createDecodingBaseline(&createDecoder, fullData.get(), &baselineHashes);
+    createDecodingBaseline(createDecoder, fullData.get(), &baselineHashes);
     size_t frameCount = baselineHashes.size();
 
     // Random decoding should get the same results as sequential decoding.
     OwnPtr<ImageDecoder> decoder = createDecoder();
     decoder->setData(fullData.get(), true);
     const size_t skippingStep = 5;
     for (size_t i = 0; i < skippingStep; ++i) {
         for (size_t j = i; j < frameCount; j += skippingStep) {
             SCOPED_TRACE(testing::Message() << "Random i:" << i << " j:" << j);
             ImageFrame* frame = decoder->frameBufferAtIndex(j);
             EXPECT_EQ(baselineHashes[j], hashBitmap(frame->getSkBitmap()));
         }
     }
 
     // Decoding in reverse order.
     decoder = createDecoder();
     decoder->setData(fullData.get(), true);
     for (size_t i = frameCount; i; --i) {
         SCOPED_TRACE(testing::Message() << "Reverse i:" << i);
         ImageFrame* frame = decoder->frameBufferAtIndex(i - 1);
         EXPECT_EQ(baselineHashes[i - 1], hashBitmap(frame->getSkBitmap()));
     }
+    LOOP_DECODERS_END
 }
 
-void testRandomDecodeAfterClearFrameBufferCache(const char* dir, const char* gifFile)
+void testRandomDecodeAfterClearFrameBufferCache(const char* dir, const char* gifFile, ImageFrame::ColorType targetType = ImageFrame::N32)
 {
     SCOPED_TRACE(gifFile);
 
     RefPtr<SharedBuffer> data = readFile(dir, gifFile);
     ASSERT_TRUE(data.get());
     Vector<unsigned> baselineHashes;
-    createDecodingBaseline(&createDecoder, data.get(), &baselineHashes);
+    DecoderCreator decoderCreator = &createDecoderIndex8;
+    if (targetType == ImageFrame::N32) {
+        decoderCreator = &createDecoderN32;
+    }
+    createDecodingBaseline(decoderCreator, data.get(), &baselineHashes);
+
     size_t frameCount = baselineHashes.size();
 
-    OwnPtr<ImageDecoder> decoder = createDecoder();
+    OwnPtr<ImageDecoder> decoder = decoderCreator();
     decoder->setData(data.get(), true);
     for (size_t clearExceptFrame = 0; clearExceptFrame < frameCount; ++clearExceptFrame) {
         decoder->clearCacheExceptFrame(clearExceptFrame);
         const size_t skippingStep = 5;
         for (size_t i = 0; i < skippingStep; ++i) {
             for (size_t j = 0; j < frameCount; j += skippingStep) {
                 SCOPED_TRACE(testing::Message() << "Random i:" << i << " j:" << j);
+                bool canDecodeToIndex8 = decoder->canDecodeTo(j, ImageFrame::Index8);
                 ImageFrame* frame = decoder->frameBufferAtIndex(j);
                 EXPECT_EQ(baselineHashes[j], hashBitmap(frame->getSkBitmap()));
+                EXPECT_EQ(canDecodeToIndex8, frame->getSkBitmap().colorType() == kIndex_8_SkColorType);
             }
         }
     }
+}
+
+void testRandomFrameDecodeCompare(const char* dir, const char* gifFile)
+{
+    SCOPED_TRACE(gifFile);
+
+    RefPtr<SharedBuffer> fullData = readFile(dir, gifFile);
+    ASSERT_TRUE(fullData.get());
+    Vector<unsigned> baselineHashes;
+    createDecodingBaseline(&createDecoderN32, fullData.get(), &baselineHashes);
+    size_t frameCount = baselineHashes.size();
+
+    // Random decoding should get the same results as sequential decoding.
+    OwnPtr<ImageDecoder> decoder = createDecoderN32();
+    // Test Index8 and RGBA through the same scenario.
+    OwnPtr<ImageDecoder> decoderI8 = createDecoderIndex8();
+
+    decoder->setData(fullData.get(), true);
+    decoderI8->setData(fullData.get(), true);
+    const size_t skippingStep = 5;
+    for (size_t i = 0; i < skippingStep; ++i) {
+        for (size_t j = i; j < frameCount; j += skippingStep) {
+            SCOPED_TRACE(testing::Message() << "Random i:" << i << " j:" << j);
+            ImageFrame* frame = decoder->frameBufferAtIndex(j);
+            EXPECT_EQ(baselineHashes[j], hashBitmap(frame->getSkBitmap()));
+            ImageFrame* frameI8 = decoderI8->frameBufferAtIndex(j);
+            ASSERT_TRUE(areFramesColorsEqual(*frame, *frameI8));
+        }
+    }
+
+    // Decoding in reverse order.
+    decoder = createDecoderN32();
+    decoderI8 = createDecoderIndex8();
+    decoder->setData(fullData.get(), true);
+    decoderI8->setData(fullData.get(), true);
+    for (size_t i = frameCount; i; --i) {
+        SCOPED_TRACE(testing::Message() << "Reverse i:" << i);
+        ImageFrame* frame = decoder->frameBufferAtIndex(i - 1);
+        EXPECT_EQ(baselineHashes[i - 1], hashBitmap(frame->getSkBitmap()));
+        ImageFrame* frameI8 = decoderI8->frameBufferAtIndex(i - 1);
+        ASSERT_TRUE(areFramesColorsEqual(*frame, *frameI8));
+    }
+}
+
+void testRandomDecodeAfterClearFrameBufferCacheCompare(const char* dir, const char* gifFile)
+{
+    SCOPED_TRACE(gifFile);
+
+    RefPtr<SharedBuffer> data = readFile(dir, gifFile);
+    ASSERT_TRUE(data.get());
+    Vector<unsigned> baselineHashes;
+    createDecodingBaseline(&createDecoderN32, data.get(), &baselineHashes);
+    size_t frameCount = baselineHashes.size();
+
+    OwnPtr<ImageDecoder> decoder = createDecoderN32();
+    // Test Index8 and RGBA through the same scenario and compare pixels.
+    OwnPtr<ImageDecoder> decoderI8 = createDecoderIndex8();
+
+    decoder->setData(data.get(), true);
+    decoderI8->setData(data.get(), true);
+    for (size_t clearExceptFrame = 0; clearExceptFrame < frameCount; ++clearExceptFrame) {
+        decoder->clearCacheExceptFrame(clearExceptFrame);
+        decoderI8->clearCacheExceptFrame(clearExceptFrame);
+        const size_t skippingStep = 5;
+        for (size_t i = 0; i < skippingStep; ++i) {
+            for (size_t j = 0; j < frameCount; j += (i + 2)) {
+                SCOPED_TRACE(testing::Message() << "Random i:" << i << " j:" << j);
+                ImageFrame* frame = decoder->frameBufferAtIndex(j);
+                EXPECT_EQ(baselineHashes[j], hashBitmap(frame->getSkBitmap()));
+                bool canDecodeToIndex8 = decoderI8->canDecodeTo(j, ImageFrame::Index8);
+                ImageFrame* frameI8 = decoderI8->frameBufferAtIndex(j);
+                EXPECT_EQ(canDecodeToIndex8, frameI8->getSkBitmap().colorType() == kIndex_8_SkColorType);
+                ASSERT_TRUE(areFramesColorsEqual(*frame, *frameI8));
+            }
+        }
+    }
 }
 
 } // anonymous namespace
 
 TEST(GIFImageDecoderTest, decodeTwoFrames)
 {
-    OwnPtr<ImageDecoder> decoder = createDecoder();
+    OwnPtr<ImageDecoder> decoder = createDecoderN32();
+    OwnPtr<ImageDecoder> decoderI8 = createDecoderIndex8();
 
     RefPtr<SharedBuffer> data = readFile(layoutTestResourcesDir, "animated.gif");
     ASSERT_TRUE(data.get());
     decoder->setData(data.get(), true);
+    decoderI8->setData(data.get(), true);
     EXPECT_EQ(cAnimationLoopOnce, decoder->repetitionCount());
 
     ImageFrame* frame = decoder->frameBufferAtIndex(0);
     uint32_t generationID0 = frame->getSkBitmap().getGenerationID();
     EXPECT_EQ(ImageFrame::FrameComplete, frame->status());
     EXPECT_EQ(16, frame->getSkBitmap().width());
     EXPECT_EQ(16, frame->getSkBitmap().height());
 
+    ImageFrame* frameI8 = decoderI8->frameBufferAtIndex(0);
+    generationID0 = frameI8->getSkBitmap().getGenerationID();
+    EXPECT_EQ(ImageFrame::FrameComplete, frameI8->status());
+    EXPECT_EQ(16, frameI8->getSkBitmap().width());
+    EXPECT_EQ(16, frameI8->getSkBitmap().height());
+
+    ASSERT_TRUE(areFramesColorsEqual(*frame, *frameI8));
+
     frame = decoder->frameBufferAtIndex(1);
     uint32_t generationID1 = frame->getSkBitmap().getGenerationID();
     EXPECT_EQ(ImageFrame::FrameComplete, frame->status());
     EXPECT_EQ(16, frame->getSkBitmap().width());
     EXPECT_EQ(16, frame->getSkBitmap().height());
     EXPECT_TRUE(generationID0 != generationID1);
 
     EXPECT_EQ(2u, decoder->frameCount());
     EXPECT_EQ(cAnimationLoopInfinite, decoder->repetitionCount());
+
+    frameI8 = decoderI8->frameBufferAtIndex(1);
+    ASSERT_TRUE(areFramesColorsEqual(*frame, *frameI8));
+    EXPECT_EQ(2u, decoderI8->frameCount());
+    EXPECT_EQ(cAnimationLoopInfinite, decoderI8->repetitionCount());
 }
 
 TEST(GIFImageDecoderTest, parseAndDecode)
 {
+    LOOP_DECODERS_BEGIN
     OwnPtr<ImageDecoder> decoder = createDecoder();
 
     RefPtr<SharedBuffer> data = readFile(layoutTestResourcesDir, "animated.gif");
     ASSERT_TRUE(data.get());
     decoder->setData(data.get(), true);
     EXPECT_EQ(cAnimationLoopOnce, decoder->repetitionCount());
 
     // This call will parse the entire file.
     EXPECT_EQ(2u, decoder->frameCount());
 
     ImageFrame* frame = decoder->frameBufferAtIndex(0);
     EXPECT_EQ(ImageFrame::FrameComplete, frame->status());
     EXPECT_EQ(16, frame->getSkBitmap().width());
     EXPECT_EQ(16, frame->getSkBitmap().height());
 
     frame = decoder->frameBufferAtIndex(1);
     EXPECT_EQ(ImageFrame::FrameComplete, frame->status());
     EXPECT_EQ(16, frame->getSkBitmap().width());
     EXPECT_EQ(16, frame->getSkBitmap().height());
     EXPECT_EQ(cAnimationLoopInfinite, decoder->repetitionCount());
+    LOOP_DECODERS_END
 }
 
 TEST(GIFImageDecoderTest, parseByteByByte)
 {
-    OwnPtr<ImageDecoder> decoder = createDecoder();
+    OwnPtr<ImageDecoder> decoder = createDecoderN32();
+    OwnPtr<ImageDecoder> decoderI8 = createDecoderIndex8();
 
     RefPtr<SharedBuffer> data = readFile(layoutTestResourcesDir, "animated.gif");
     ASSERT_TRUE(data.get());
 
     size_t frameCount = 0;
 
     // Pass data to decoder byte by byte.
     for (size_t length = 1; length <= data->size(); ++length) {
         RefPtr<SharedBuffer> tempData = SharedBuffer::create(data->data(), length);
         decoder->setData(tempData.get(), length == data->size());
+        decoderI8->setData(tempData.get(), length == data->size());
 
         EXPECT_LE(frameCount, decoder->frameCount());
+        EXPECT_LE(frameCount, decoderI8->frameCount());
+        EXPECT_EQ(decoder->frameCount(), decoderI8->frameCount());
         frameCount = decoder->frameCount();
     }
 
     EXPECT_EQ(2u, decoder->frameCount());
 
     decoder->frameBufferAtIndex(0);
     decoder->frameBufferAtIndex(1);
     EXPECT_EQ(cAnimationLoopInfinite, decoder->repetitionCount());
 }
 
 TEST(GIFImageDecoderTest, parseAndDecodeByteByByte)
 {
-    OwnPtr<ImageDecoder> decoder = createDecoder();
+    OwnPtr<ImageDecoder> decoder = createDecoderN32();
+    OwnPtr<ImageDecoder> decoderI8 = createDecoderIndex8();
 
     RefPtr<SharedBuffer> data = readFile(layoutTestResourcesDir, "animated-gif-with-offsets.gif");
     ASSERT_TRUE(data.get());
 
     size_t frameCount = 0;
     size_t framesDecoded = 0;
 
     // Pass data to decoder byte by byte.
     for (size_t length = 1; length <= data->size(); ++length) {
         RefPtr<SharedBuffer> tempData = SharedBuffer::create(data->data(), length);
         decoder->setData(tempData.get(), length == data->size());
+        decoderI8->setData(tempData.get(), length == data->size());
 
         EXPECT_LE(frameCount, decoder->frameCount());
         frameCount = decoder->frameCount();
+        EXPECT_EQ(frameCount, decoderI8->frameCount());
 
         ImageFrame* frame = decoder->frameBufferAtIndex(frameCount - 1);
         if (frame && frame->status() == ImageFrame::FrameComplete && framesDecoded < frameCount)
             ++framesDecoded;
+
+        ImageFrame* frameI8 = decoderI8->frameBufferAtIndex(frameCount - 1);
+        ASSERT_TRUE(!(frame || frameI8) || areFramesColorsEqual(*frame, *frameI8));
     }
 
     EXPECT_EQ(5u, decoder->frameCount());
     EXPECT_EQ(5u, framesDecoded);
     EXPECT_EQ(cAnimationLoopInfinite, decoder->repetitionCount());
 }
 
 TEST(GIFImageDecoderTest, brokenSecondFrame)
 {
+    LOOP_DECODERS_BEGIN
     OwnPtr<ImageDecoder> decoder = createDecoder();
 
     RefPtr<SharedBuffer> data = readFile(webTestsDataDir, "broken.gif");
     ASSERT_TRUE(data.get());
     decoder->setData(data.get(), true);
 
     // One frame is detected but cannot be decoded.
     EXPECT_EQ(1u, decoder->frameCount());
     ImageFrame* frame = decoder->frameBufferAtIndex(1);
     EXPECT_FALSE(frame);
+    LOOP_DECODERS_END
 }
 
 TEST(GIFImageDecoderTest, progressiveDecode)
 {
+    LOOP_DECODERS_BEGIN
     RefPtr<SharedBuffer> fullData = readFile(webTestsDataDir, "radient.gif");
     ASSERT_TRUE(fullData.get());
     const size_t fullLength = fullData->size();
 
     OwnPtr<ImageDecoder> decoder;
     ImageFrame* frame;
 
     Vector<unsigned> truncatedHashes;
     Vector<unsigned> progressiveHashes;
 
@@ skipping 27 matching lines @@
     EXPECT_EQ(cAnimationNone, decoder->repetitionCount());
 
     bool match = true;
     for (size_t i = 0; i < truncatedHashes.size(); ++i) {
         if (truncatedHashes[i] != progressiveHashes[i]) {
             match = false;
             break;
         }
     }
     EXPECT_TRUE(match);
+    LOOP_DECODERS_END
 }
 
 TEST(GIFImageDecoderTest, allDataReceivedTruncation)
 {
+    LOOP_DECODERS_BEGIN
     OwnPtr<ImageDecoder> decoder = createDecoder();
 
     RefPtr<SharedBuffer> data = readFile(layoutTestResourcesDir, "animated.gif");
     ASSERT_TRUE(data.get());
 
     ASSERT_GE(data->size(), 10u);
     RefPtr<SharedBuffer> tempData = SharedBuffer::create(data->data(), data->size() - 10);
     decoder->setData(tempData.get(), true);
 
     EXPECT_EQ(2u, decoder->frameCount());
     EXPECT_FALSE(decoder->failed());
 
     decoder->frameBufferAtIndex(0);
     EXPECT_FALSE(decoder->failed());
     decoder->frameBufferAtIndex(1);
     EXPECT_TRUE(decoder->failed());
+    LOOP_DECODERS_END
 }
 
 TEST(GIFImageDecoderTest, frameIsComplete)
 {
+    LOOP_DECODERS_BEGIN
     OwnPtr<ImageDecoder> decoder = createDecoder();
 
     RefPtr<SharedBuffer> data = readFile(layoutTestResourcesDir, "animated.gif");
     ASSERT_TRUE(data.get());
     decoder->setData(data.get(), true);
 
     EXPECT_EQ(2u, decoder->frameCount());
     EXPECT_FALSE(decoder->failed());
     EXPECT_TRUE(decoder->frameIsCompleteAtIndex(0));
     EXPECT_TRUE(decoder->frameIsCompleteAtIndex(1));
     EXPECT_EQ(cAnimationLoopInfinite, decoder->repetitionCount());
+    LOOP_DECODERS_END
 }
 
 TEST(GIFImageDecoderTest, frameIsCompleteLoading)
 {
+    LOOP_DECODERS_BEGIN
     OwnPtr<ImageDecoder> decoder = createDecoder();
 
     RefPtr<SharedBuffer> data = readFile(layoutTestResourcesDir, "animated.gif");
     ASSERT_TRUE(data.get());
 
     ASSERT_GE(data->size(), 10u);
     RefPtr<SharedBuffer> tempData = SharedBuffer::create(data->data(), data->size() - 10);
     decoder->setData(tempData.get(), false);
 
     EXPECT_EQ(2u, decoder->frameCount());
     EXPECT_FALSE(decoder->failed());
     EXPECT_TRUE(decoder->frameIsCompleteAtIndex(0));
     EXPECT_FALSE(decoder->frameIsCompleteAtIndex(1));
 
     decoder->setData(data.get(), true);
     EXPECT_EQ(2u, decoder->frameCount());
     EXPECT_TRUE(decoder->frameIsCompleteAtIndex(0));
     EXPECT_TRUE(decoder->frameIsCompleteAtIndex(1));
+    LOOP_DECODERS_END
 }
 
 TEST(GIFImageDecoderTest, badTerminator)
 {
+    LOOP_DECODERS_BEGIN
     RefPtr<SharedBuffer> referenceData = readFile(webTestsDataDir, "radient.gif");
     RefPtr<SharedBuffer> testData = readFile(webTestsDataDir, "radient-bad-terminator.gif");
     ASSERT_TRUE(referenceData.get());
     ASSERT_TRUE(testData.get());
 
     OwnPtr<ImageDecoder> referenceDecoder = createDecoder();
     referenceDecoder->setData(referenceData.get(), true);
     EXPECT_EQ(1u, referenceDecoder->frameCount());
     ImageFrame* referenceFrame = referenceDecoder->frameBufferAtIndex(0);
     ASSERT(referenceFrame);
 
     OwnPtr<ImageDecoder> testDecoder = createDecoder();
     testDecoder->setData(testData.get(), true);
     EXPECT_EQ(1u, testDecoder->frameCount());
     ImageFrame* testFrame = testDecoder->frameBufferAtIndex(0);
     ASSERT(testFrame);
 
     EXPECT_EQ(hashBitmap(referenceFrame->getSkBitmap()), hashBitmap(testFrame->getSkBitmap()));
+    LOOP_DECODERS_END
 }
 
 TEST(GIFImageDecoderTest, updateRequiredPreviousFrameAfterFirstDecode)
 {
+    LOOP_DECODERS_BEGIN
     OwnPtr<ImageDecoder> decoder = createDecoder();
 
     RefPtr<SharedBuffer> fullData = readFile(layoutTestResourcesDir, "animated-10color.gif");
     ASSERT_TRUE(fullData.get());
 
     // Give it data that is enough to parse but not decode in order to check the status
     // of requiredPreviousFrameIndex before decoding.
     size_t partialSize = 1;
     do {
         RefPtr<SharedBuffer> data = SharedBuffer::create(fullData->data(), partialSize);
         decoder->setData(data.get(), false);
         ++partialSize;
     } while (!decoder->frameCount() || decoder->frameBufferAtIndex(0)->status() == ImageFrame::FrameEmpty);
 
     EXPECT_EQ(kNotFound, decoder->frameBufferAtIndex(0)->requiredPreviousFrameIndex());
     unsigned frameCount = decoder->frameCount();
     for (size_t i = 1; i < frameCount; ++i)
         EXPECT_EQ(i - 1, decoder->frameBufferAtIndex(i)->requiredPreviousFrameIndex());
 
     decoder->setData(fullData.get(), true);
     for (size_t i = 0; i < frameCount; ++i)
         EXPECT_EQ(kNotFound, decoder->frameBufferAtIndex(i)->requiredPreviousFrameIndex());
+    LOOP_DECODERS_END
 }
 
 TEST(GIFImageDecoderTest, randomFrameDecode)
 {
     // Single frame image.
     testRandomFrameDecode(webTestsDataDir, "radient.gif");
     // Multiple frame images.
     testRandomFrameDecode(layoutTestResourcesDir, "animated-gif-with-offsets.gif");
     testRandomFrameDecode(layoutTestResourcesDir, "animated-10color.gif");
 }
 
+TEST(GIFImageDecoderTest, randomFrameDecodeCompare)
+{
+    // Single frame image.
+    testRandomFrameDecodeCompare(webTestsDataDir, "radient.gif");
+    // Multiple frame images.
+    testRandomFrameDecodeCompare(layoutTestResourcesDir, "animated-gif-with-offsets.gif");
+    testRandomFrameDecodeCompare(layoutTestResourcesDir, "animated-10color.gif");
+}
+
 TEST(GIFImageDecoderTest, randomDecodeAfterClearFrameBufferCache)
 {
     // Single frame image.
     testRandomDecodeAfterClearFrameBufferCache(webTestsDataDir, "radient.gif");
     // Multiple frame images.
     testRandomDecodeAfterClearFrameBufferCache(layoutTestResourcesDir, "animated-gif-with-offsets.gif");
     testRandomDecodeAfterClearFrameBufferCache(layoutTestResourcesDir, "animated-10color.gif");
 }
 
+TEST(GIFImageDecoderTest, randomDecodeAfterClearFrameBufferCacheCompare)
+{
+    // Single frame image.
+    testRandomDecodeAfterClearFrameBufferCacheCompare(webTestsDataDir, "radient.gif");
+    // Multiple frame images with offset. All frames depend to frame 0.
+    testRandomDecodeAfterClearFrameBufferCacheCompare(layoutTestResourcesDir, "animated-gif-with-offsets.gif");
+    testRandomDecodeAfterClearFrameBufferCacheCompare(layoutTestResourcesDir, "animated-10color.gif");
+}
+
 TEST(GIFImageDecoderTest, resumePartialDecodeAfterClearFrameBufferCache)
 {
     RefPtr<SharedBuffer> fullData = readFile(layoutTestResourcesDir, "animated-10color.gif");
     ASSERT_TRUE(fullData.get());
+
+    LOOP_DECODERS_BEGIN
     Vector<unsigned> baselineHashes;
-    createDecodingBaseline(&createDecoder, fullData.get(), &baselineHashes);
+    createDecodingBaseline(createDecoder, fullData.get(), &baselineHashes);
     size_t frameCount = baselineHashes.size();
 
     OwnPtr<ImageDecoder> decoder = createDecoder();
 
     // Let frame 0 be partially decoded.
     size_t partialSize = 1;
     do {
         RefPtr<SharedBuffer> data = SharedBuffer::create(fullData->data(), partialSize);
         decoder->setData(data.get(), false);
         ++partialSize;
     } while (!decoder->frameCount() || decoder->frameBufferAtIndex(0)->status() == ImageFrame::FrameEmpty);
 
     // Skip to the last frame and clear.
     decoder->setData(fullData.get(), true);
     EXPECT_EQ(frameCount, decoder->frameCount());
     ImageFrame* lastFrame = decoder->frameBufferAtIndex(frameCount - 1);
     EXPECT_EQ(baselineHashes[frameCount - 1], hashBitmap(lastFrame->getSkBitmap()));
     decoder->clearCacheExceptFrame(kNotFound);
 
     // Resume decoding of the first frame.
     ImageFrame* firstFrame = decoder->frameBufferAtIndex(0);
     EXPECT_EQ(ImageFrame::FrameComplete, firstFrame->status());
     EXPECT_EQ(baselineHashes[0], hashBitmap(firstFrame->getSkBitmap()));
+    LOOP_DECODERS_END
 }
 
 // The first LZW codes in the image are invalid values that try to create a loop
 // in the dictionary. Decoding should fail, but not infinitely loop or corrupt memory.
 TEST(GIFImageDecoderTest, badInitialCode)
 {
     RefPtr<SharedBuffer> testData = readFile(decodersTestingDir, "bad-initial-code.gif");
     ASSERT_TRUE(testData.get());
 
+    LOOP_DECODERS_BEGIN
     OwnPtr<ImageDecoder> testDecoder = createDecoder();
     testDecoder->setData(testData.get(), true);
     EXPECT_EQ(1u, testDecoder->frameCount());
     ASSERT_TRUE(testDecoder->frameBufferAtIndex(0));
     EXPECT_TRUE(testDecoder->failed());
+    LOOP_DECODERS_END
 }
 
 // The image has an invalid LZW code that exceeds dictionary size. Decoding should fail.
 TEST(GIFImageDecoderTest, badCode)
 {
     RefPtr<SharedBuffer> testData = readFile(decodersTestingDir, "bad-code.gif");
     ASSERT_TRUE(testData.get());
 
+    LOOP_DECODERS_BEGIN
     OwnPtr<ImageDecoder> testDecoder = createDecoder();
     testDecoder->setData(testData.get(), true);
     EXPECT_EQ(1u, testDecoder->frameCount());
     ASSERT_TRUE(testDecoder->frameBufferAtIndex(0));
     EXPECT_TRUE(testDecoder->failed());
+    LOOP_DECODERS_END
 }
 
 TEST(GIFImageDecoderTest, invalidDisposalMethod)
 {
+    LOOP_DECODERS_BEGIN
     OwnPtr<ImageDecoder> decoder = createDecoder();
 
     // The image has 2 frames, with disposal method 4 and 5, respectively.
     RefPtr<SharedBuffer> data = readFile(webTestsDataDir, "invalid-disposal-method.gif");
     ASSERT_TRUE(data.get());
     decoder->setData(data.get(), true);
 
     EXPECT_EQ(2u, decoder->frameCount());
     // Disposal method 4 is converted to ImageFrame::DisposeOverwritePrevious.
     EXPECT_EQ(ImageFrame::DisposeOverwritePrevious, decoder->frameBufferAtIndex(0)->disposalMethod());
     // Disposal method 5 is ignored.
     EXPECT_EQ(ImageFrame::DisposeNotSpecified, decoder->frameBufferAtIndex(1)->disposalMethod());
+    LOOP_DECODERS_END
 }
 
 TEST(GIFImageDecoderTest, firstFrameHasGreaterSizeThanScreenSize)
 {
     RefPtr<SharedBuffer> fullData = readFile(decodersTestingDir, "first-frame-has-greater-size-than-screen-size.gif");
     ASSERT_TRUE(fullData.get());
-
+    LOOP_DECODERS_BEGIN
     OwnPtr<ImageDecoder> decoder;
     IntSize frameSize;
 
     // Compute hashes when the file is truncated.
     for (size_t i = 1; i <= fullData->size(); ++i) {
         decoder = createDecoder();
         RefPtr<SharedBuffer> data = SharedBuffer::create(fullData->data(), i);
         decoder->setData(data.get(), i == fullData->size());
 
         if (decoder->isSizeAvailable() && !frameSize.width() && !frameSize.height()) {
             frameSize = decoder->decodedSize();
             continue;
         }
 
         ASSERT_EQ(frameSize.width(), decoder->decodedSize().width());
         ASSERT_EQ(frameSize.height(), decoder->decodedSize().height());
     }
+    LOOP_DECODERS_END
 }
 
+TEST(GIFImageDecoderTest, convertInFrameGenerator)
+{
+    RefPtr<SharedBuffer> fullData = readFile(layoutTestResourcesDir, "animated-10color.gif");
+    ASSERT_TRUE(fullData.get());
+    OwnPtr<ImageDecoder> decoder = createDecoderIndex8();
+    decoder->setData(fullData.get(), true);
+    ImageFrame* firstFrame = decoder->frameBufferAtIndex(0);
+    ASSERT_TRUE(firstFrame->bitmap().colorType() == kIndex_8_SkColorType);
+    const SkBitmap index8Bitmap = firstFrame->bitmap();
+    SkBitmap target;
+    target.setInfo(SkImageInfo::MakeN32(firstFrame->bitmap().width(), firstFrame->bitmap().height(), index8Bitmap.alphaType()));
+    target.allocPixels();
+
+    RefPtr<ImageFrameGenerator> m_generator = ImageFrameGenerator::create(firstFrame->bitmap().info().dimensions(), fullData, true);
+    ImageDecodingStore::instance().setCacheLimitInBytes(1024 * 1024);
+    ImageDecodingStore::instance().insertDecoder(m_generator.get(), decoder.release());
+    SkAutoLockPixels lock(target);
+    m_generator->decodeAndScale(target.info(), 0, target.getPixels(), target.rowBytes());
+    ImageDecodingStore::instance().clear();
+    SkAutoLockPixels lockI8(index8Bitmap);
+    ASSERT_TRUE(areBitmapsColorsEqual(target, index8Bitmap));
+}
+
+// FIXME following benchmarks need to be removed before submitting.
+#define BENCHMARK_DECODE(dir, file, title, count)\
+TEST(GIFImageDecoderTest, tempBench_decodeIndex8##title##warmuprun)\
+{\
+    testRandomDecodeAfterClearFrameBufferCache(dir, file);\
+}\
+TEST(GIFImageDecoderTest, tempBench_decodeN32##title##_x##count) \
+{\
+    for (int i = 0; i < count; ++i)\
+        testRandomDecodeAfterClearFrameBufferCache(dir, file);\
+}\
+\
+TEST(GIFImageDecoderTest, tempBench_decodeIndex8##title##_x##count)\
+{\
+    for (int i = 0; i < count; ++i)\
+        testRandomDecodeAfterClearFrameBufferCache(dir, file, ImageFrame::Index8);\
+}\
+
+BENCHMARK_DECODE(layoutTestResourcesDir, "animated-10color.gif", animated_10color_gif, 5)
+BENCHMARK_DECODE(webTestsDataDir, "radient.gif", radient_gif, 10)
+BENCHMARK_DECODE(layoutTestResourcesDir, "animated-gif-with-offsets.gif", animated_gif_with_offsets_gif, 5)
+BENCHMARK_DECODE(layoutTestResourcesDir, "animated.gif", animated_gif, 10)
+BENCHMARK_DECODE(layoutTestResourcesDir, "quicksort.gif", quicksort_gif, 5)
+BENCHMARK_DECODE(layoutTestResourcesDir, "large-gif-checkerboard.gif", large_gif_checkerboard_gif, 5)
+BENCHMARK_DECODE(layoutTestResourcesDir, "3dolph.gif", 3dolph_gif, 5)
 } // namespace blink