JPEG YUV Decoding

include/core/SkImageDecoder.h

Index: include/core/SkImageDecoder.h
diff --git a/include/core/SkImageDecoder.h b/include/core/SkImageDecoder.h
index 5910d33a997a4950aad0694d1beb0619f6edb31b..94831762deaf4f4ef58131e831769093761a5cc4 100644
--- a/include/core/SkImageDecoder.h
+++ b/include/core/SkImageDecoder.h
@@ -47,6 +47,15 @@ public:
     */
     virtual Format getFormat() const;
 
+    /** If planes or rowBytes is NULL, decodes the header and computes componentSizes
+        for memory allocation.
+        Otherwise, decodes the YUV planes into the provided image planes and
+        updates componentSizes to the final image size.
+        Returns whether the decoding was successful.
+    */
+    bool decodeYUV8Planes(SkStream* stream, SkISize componentSizes[3], void* planes[3],
+                          size_t rowBytes[3], SkYUVColorSpace*);
+
     /** Return the format of the SkStreamRewindable or kUnknown_Format if it cannot be determined.
         Rewinds the stream before returning.
     */
@@ -339,6 +348,17 @@ protected:
         return false;
     }
 
+    /** If planes or rowBytes is NULL, decodes the header and computes componentSizes
+        for memory allocation.
+        Otherwise, decodes the YUV planes into the provided image planes and
+        updates componentSizes to the final image size.
+        Returns whether the decoding was successful.
+    */
+    virtual bool onDecodeYUV8Planes(SkStream* stream, SkISize componentSizes[3], void* planes[3],
+                                    size_t rowBytes[3], SkYUVColorSpace*) {
+        return false;
+    }
+
     /*
      * Crop a rectangle from the src Bitmap to the dest Bitmap. src and dst are
      * both sampled by sampleSize from an original Bitmap.