Add getYUV8Planes() API to SkCodec

include/codec/SkCodec.h

Index: include/codec/SkCodec.h
diff --git a/include/codec/SkCodec.h b/include/codec/SkCodec.h
index d06c2c3399e4858e30626945948f4933f5d059c6..c4b4fd12e6c0eb45804413dc07a7a5e1b3bc411b 100644
--- a/include/codec/SkCodec.h
+++ b/include/codec/SkCodec.h
@@ -278,6 +278,45 @@ public:
     Result getPixels(const SkImageInfo& info, void* pixels, size_t rowBytes);
 
     /**
+     *  If decoding to YUV is supported, this returns true and populates "sizes" with
+     *  the appropriate sizes of the Y, U, and V planes.
+     */
+    bool getYUV8Sizes(SkISize sizes[3]) const {
+        if (nullptr == sizes) {
+            return false;
+        }
+
+        return this->onGetYUV8Sizes(sizes);
+    }
+
+    /**
+     *  @param sizes      Sizes of each of the Y, U, and V planes
+     *  @param pixels     Memory for each of the Y, U, and V planes
+     *  @param rowBytes   Row bytes for each of the Y, U, and V planes
+     *  @param colorSpace If nullptr, this parameter is ignored.  Otherwise,
+     *                    if the decode is successful, this will bet set to
+     *                    kJPEG_SkYUVColorSpace (JPEG is currently the only
+     *                    format that supports YUV).
+     *
+     *  Returns kSuccess, or another value explaining the type of failure.
+     *  This always attempts to perform a full decode.  If the client only
+     *  wants size, it should call getYUV8Sizes().
+     */
+    Result getYUV8Planes(SkISize sizes[3], void* pixels[3], size_t rowBytes[3],
+            SkYUVColorSpace* colorSpace) {
+        if (nullptr == sizes || nullptr == pixels || nullptr == pixels[0] ||
+                nullptr == pixels[1] || nullptr == pixels[2] || nullptr == rowBytes) {
+            return kInvalidInput;
+        }
+
+        if (!this->rewindIfNeeded()) {
+            return kCouldNotRewind;
+        }
+
+        return this->onGetYUV8Planes(sizes, pixels, rowBytes, colorSpace);
+    }
+
+    /**
      *  Some images may initially report that they have alpha due to the format
      *  of the encoded data, but then never use any colors which have alpha
      *  less than 100%. This function can be called *after* decoding to
@@ -454,7 +493,7 @@ public:
 protected:
     SkCodec(const SkImageInfo&, SkStream*);
 
-    virtual SkISize onGetScaledDimensions(float /* desiredScale */) const {
+    virtual SkISize onGetScaledDimensions(float /*desiredScale*/) const {

[msarett, 2015/12/22 21:01:36]

Just changing the comments here to be consistent with the rest of the file.

         // By default, scaling is not supported.
         return this->getInfo().dimensions();
     }
@@ -481,7 +520,16 @@ protected:
                                SkPMColor ctable[], int* ctableCount,
                                int* rowsDecoded) = 0;
 
-    virtual bool onGetValidSubset(SkIRect* /* desiredSubset */) const {
+    virtual bool onGetYUV8Sizes(SkISize* /*sizes*/) const {
+        return false;
+    }
+
+    virtual Result onGetYUV8Planes(SkISize* /*sizes*/, void** /*pixels*/, size_t* /*rowBytes*/,
+            SkYUVColorSpace* /*colorSpace*/) {
+        return kUnimplemented;
+    }
+
+    virtual bool onGetValidSubset(SkIRect* /*desiredSubset*/) const {
         // By default, subsets are not supported.
         return false;
     }