Bug 1292505 (Part 1b) - Update DecoderFactory to use SetOutputSize(), and propagate the changes to RasterImage. r=edwin

image/DecoderFactory.cpp

@@ -109,7 +109,7 @@ DecoderFactory::CreateDecoder(DecoderType aType,
                               NotNull<RasterImage*> aImage,
                               NotNull<SourceBuffer*> aSourceBuffer,
                               const IntSize& aIntrinsicSize,
-                              const Maybe<IntSize>& aTargetSize,
+                              const IntSize& aOutputSize,
                               DecoderFlags aDecoderFlags,
                               SurfaceFlags aSurfaceFlags,
                               int aSampleSize)
@@ -125,25 +125,19 @@ DecoderFactory::CreateDecoder(DecoderType aType,
   // Initialize the decoder.
   decoder->SetMetadataDecode(false);
   decoder->SetIterator(aSourceBuffer->Iterator());
+  decoder->SetOutputSize(aOutputSize);
   decoder->SetDecoderFlags(aDecoderFlags | DecoderFlags::FIRST_FRAME_ONLY);
   decoder->SetSurfaceFlags(aSurfaceFlags);
   decoder->SetSampleSize(aSampleSize);
 
-  // Set a target size for downscale-during-decode if applicable.
-  if (aTargetSize) {
-    DebugOnly<nsresult> rv = decoder->SetTargetSize(*aTargetSize);
-    MOZ_ASSERT(NS_SUCCEEDED(rv), "Bad downscale-during-decode target size?");
-  }
-
   if (NS_FAILED(decoder->Init())) {
     return nullptr;
   }
 
   // Add a placeholder to the SurfaceCache so we won't trigger any more decoders
   // with the same parameters.
-  IntSize surfaceSize = aTargetSize.valueOr(aIntrinsicSize);
   SurfaceKey surfaceKey =
-    RasterSurfaceKey(surfaceSize, aSurfaceFlags, /* aFrameNum = */ 0);
+    RasterSurfaceKey(aOutputSize, aSurfaceFlags, /* aFrameNum = */ 0);
   InsertOutcome outcome =
     SurfaceCache::InsertPlaceholder(ImageKey(aImage.get()), surfaceKey);
   if (outcome != InsertOutcome::SUCCESS) {
@@ -254,16 +248,10 @@ DecoderFactory::CreateDecoderForICOResource(DecoderType aType,
   // Initialize the decoder, copying settings from @aICODecoder.
   decoder->SetMetadataDecode(aICODecoder->IsMetadataDecode());
   decoder->SetIterator(aSourceBuffer->Iterator());
+  decoder->SetOutputSize(aICODecoder->OutputSize());
   decoder->SetDecoderFlags(aICODecoder->GetDecoderFlags());
   decoder->SetSurfaceFlags(aICODecoder->GetSurfaceFlags());
 
-  // Set a target size for downscale-during-decode if applicable.
-  const Maybe<IntSize> targetSize = aICODecoder->GetTargetSize();
-  if (targetSize) {
-    DebugOnly<nsresult> rv = decoder->SetTargetSize(*targetSize);
-    MOZ_ASSERT(NS_SUCCEEDED(rv), "Bad downscale-during-decode target size?");
-  }
-
   if (NS_FAILED(decoder->Init())) {
     return nullptr;
   }
@@ -274,7 +262,7 @@ DecoderFactory::CreateDecoderForICOResource(DecoderType aType,
 /* static */ already_AddRefed<Decoder>
 DecoderFactory::CreateAnonymousDecoder(DecoderType aType,
                                        NotNull<SourceBuffer*> aSourceBuffer,
-                                       const Maybe<IntSize>& aTargetSize,
+                                       const Maybe<IntSize>& aOutputSize,
                                        SurfaceFlags aSurfaceFlags)
 {
   if (aType == DecoderType::UNKNOWN) {
@@ -303,10 +291,9 @@ DecoderFactory::CreateAnonymousDecoder(DecoderType aType,
   decoder->SetDecoderFlags(decoderFlags);
   decoder->SetSurfaceFlags(aSurfaceFlags);
 
-  // Set a target size for downscale-during-decode if applicable.
-  if (aTargetSize) {
-    DebugOnly<nsresult> rv = decoder->SetTargetSize(*aTargetSize);
-    MOZ_ASSERT(NS_SUCCEEDED(rv), "Bad downscale-during-decode target size?");
+  // Set an output size for downscale-during-decode if requested.
+  if (aOutputSize) {
+    decoder->SetOutputSize(*aOutputSize);
   }
 
   if (NS_FAILED(decoder->Init())) {

image/DecoderFactory.h

@@ -57,10 +57,9 @@ public:
    *                      from.
    * @param aIntrinsicSize The intrinsic size of the image, normally obtained
    *                       during the metadata decode.
-   * @param aTargetSize If not Nothing(), the target size which the image should
-   *                    be scaled to during decoding. It's an error to specify
-   *                    a target size for a decoder type which doesn't support
-   *                    downscale-during-decode.
+   * @param aOutputSize The output size for the decoder. If this is smaller than
+   *                    the intrinsic size, the decoder will downscale the
+   *                    image.
    * @param aDecoderFlags Flags specifying the behavior of this decoder.
    * @param aSurfaceFlags Flags specifying the type of output this decoder
    *                      should produce.
@@ -72,7 +71,7 @@ public:
                 NotNull<RasterImage*> aImage,
                 NotNull<SourceBuffer*> aSourceBuffer,
                 const gfx::IntSize& aIntrinsicSize,
-                const Maybe<gfx::IntSize>& aTargetSize,
+                const gfx::IntSize& aOutputSize,
                 DecoderFlags aDecoderFlags,
                 SurfaceFlags aSurfaceFlags,
                 int aSampleSize);
@@ -150,17 +149,17 @@ public:
    * @param aType Which type of decoder to create - JPEG, PNG, etc.
    * @param aSourceBuffer The SourceBuffer which the decoder will read its data
    *                      from.
-   * @param aTargetSize If not Nothing(), the target size which the image should
-   *                    be scaled to during decoding. It's an error to specify
-   *                    a target size for a decoder type which doesn't support
-   *                    downscale-during-decode.
+   * @param aOutputSize If Some(), the output size for the decoder. If this is
+   *                    smaller than the intrinsic size, the decoder will
+   *                    downscale the image. If Nothing(), the output size will
+   *                    be the intrinsic size.
    * @param aSurfaceFlags Flags specifying the type of output this decoder
    *                      should produce.
    */
   static already_AddRefed<Decoder>
   CreateAnonymousDecoder(DecoderType aType,
                          NotNull<SourceBuffer*> aSourceBuffer,
-                         const Maybe<gfx::IntSize>& aTargetSize,
+                         const Maybe<gfx::IntSize>& aOutputSize,
                          SurfaceFlags aSurfaceFlags);
 
   /**

image/RasterImage.cpp

@@ -1134,8 +1134,6 @@ RasterImage::Decode(const IntSize& aSize, uint32_t aFlags)
   // expire.
   SurfaceCache::UnlockEntries(ImageKey(this));
 
-  Maybe<IntSize> targetSize = mSize != aSize ? Some(aSize) : Nothing();
-
   // Determine which flags we need to decode this image with.
   DecoderFlags decoderFlags = DefaultDecoderFlags();
   if (aFlags & FLAG_ASYNC_NOTIFY) {
@@ -1163,7 +1161,7 @@ RasterImage::Decode(const IntSize& aSize, uint32_t aFlags)
                                                   decoderFlags, surfaceFlags);
   } else {
     task = DecoderFactory::CreateDecoder(mDecoderType, WrapNotNull(this),
-                                         mSourceBuffer, mSize, targetSize,
+                                         mSourceBuffer, mSize, aSize,
                                          decoderFlags, surfaceFlags,
                                          mRequestedSampleSize);
   }