Make SkCodec more flexible about its required frame
SkCodec sets fRequiredFrame to be the earliest possible frame that a
given frame can depend on. e.g.
- Frame A fills the screen, Keep
- Frame B does not cover A, Keep
- Frame C covers B but not A, and is opaque
Frame C can depend on either A or B. SkCodec already reports that C
depends on A. This CL allows a client of SkCodec to use either A or
B to create C.
Also expose the DisposalMethod. Since any frame between A and C can
be used to create C except for DisposePrevious frames, the client
needs to be able to know the disposal method so they do not try to
use such a frame to create C.
Further, the disposal method can be used to give the client a better
idea whether they will continue to need a frame. (e.g. if frame i is
DisposePrevious and depends on i-1, the client may not want to steal
i-1 to create i, since i+1 may also depend on i-1.)
TODO: Share code for decoding prior frames between GIF and WEBP
Change-Id: I91a5ae22ba3d8dfbe0bde833fa67ae3da0d81ed6
Reviewed-on: https://skia-review.googlesource.com/13722
Reviewed-by: Mike Reed <reed@google.com>
Reviewed-by: Chris Blume <cblume@chromium.org>
Reviewed-by: Matt Sarett <msarett@google.com>
Commit-Queue: Leon Scroggins <scroggo@google.com>
diff --git a/dm/DMSrcSink.cpp b/dm/DMSrcSink.cpp
index 983a0c1..4ac7e80 100644
--- a/dm/DMSrcSink.cpp
+++ b/dm/DMSrcSink.cpp
@@ -504,9 +504,9 @@
&& priorFramePixels.get()) {
// Copy into pixels
memcpy(pixels.get(), priorFramePixels.get(), safeSize);
- options.fHasPriorFrame = true;
+ options.fPriorFrame = reqFrame;
} else {
- options.fHasPriorFrame = false;
+ options.fPriorFrame = SkCodec::kNone;
}
SkCodec::Result result = codec->getPixels(decodeInfo, pixels.get(),
rowBytes, &options,