03588412c8
The old code made the wrong assumptions about premultiplication.
There are three relevant steps here for decoding a webp frame:
1 tell libwebp to decode
2 colorXform the result (sometimes)
3 blend with the prior frame (sometimes)
Rearrange the code to premultiply at the blend step, in a linear space.
If the client wants unpremul, the blend step will unpremul after.
If there is no blending, the colorXform (if any) will premultiply.
If only step 1 is necessary, let libwebp premultiply.
This fixes an animated image that has an opaque frame 0 followed by a
frame with alpha that blends with it.
Add the test image that failed (https://mathiasbynens.be/demo/animated-webp)
The prior fix is in
|
||
---|---|---|
.. | ||
common.py | ||
create_and_upload.py | ||
create.py | ||
download.py | ||
upload.py | ||
VERSION |