JPEG YUV Decoding

src/images/SkDecodingImageGenerator.cpp

Index: src/images/SkDecodingImageGenerator.cpp
diff --git a/src/images/SkDecodingImageGenerator.cpp b/src/images/SkDecodingImageGenerator.cpp
index dfa093becc5d5ff7162727729d04e175fe1d18f0..975a93aa035a4fd38e7bc34edb3d5285f44d15e3 100644
--- a/src/images/SkDecodingImageGenerator.cpp
+++ b/src/images/SkDecodingImageGenerator.cpp
@@ -45,6 +45,7 @@ protected:
     virtual bool onGetPixels(const SkImageInfo& info,
                              void* pixels, size_t rowBytes,
                              SkPMColor ctable[], int* ctableCount) SK_OVERRIDE;
+    virtual bool onGetYUV8Planes(SkISize sizes[3], void* planes[3], size_t rowBytes[3]) SK_OVERRIDE;
 
 private:
     typedef SkImageGenerator INHERITED;
@@ -209,6 +210,26 @@ bool DecodingImageGenerator::onGetPixels(const SkImageInfo& info,
     return true;
 }
 
+bool DecodingImageGenerator::onGetYUV8Planes(SkISize sizes[3], void* planes[3],
+                                             size_t rowBytes[3]) {
+    if (!fStream->rewind()) {
+        return false;
+    }
+
+    SkAutoTDelete<SkImageDecoder> decoder(SkImageDecoder::Factory(fStream));
+    if (NULL == decoder.get()) {
+        return false;
+    }
+
+    if (planes && (NULL != planes[0]) && (NULL != planes[1]) && (NULL != planes[2]) &&
+        rowBytes && (0 != rowBytes[0]) && (0 != rowBytes[1]) && (0 != rowBytes[2])) {
+        decoder->setYUVBuffers(planes, rowBytes);
+        return this->onGetPixels(fInfo, NULL, 0, NULL, NULL);
+    }
+    
+    return decoder->getComponentSizes(fStream, sizes);
+}
+
 // A contructor-type function that returns NULL on failure.  This
 // prevents the returned SkImageGenerator from ever being in a bad
 // state.  Called by both Create() functions