Closed GoogleCodeExporter closed 8 years ago
This is, in fact, and invalid file.
The VP8X chunk in the file has 'Alpha bit' set, but none of the frames contain
transparency information.
If you look at the spec
(https://developers.google.com/speed/webp/docs/riff_container?hl=en#extended_fil
e_format):
<Quote>
Alpha (L): 1 bit
Set if any of the frames of the image contain transparency information
("alpha").
<Unquote>
The WebPDemux library is just being tolerant about it, but WebPMux library is
strict and rejects the file as invalid.
This is actually a problem with ffmpeg's WebP muxer code: it always sets alpha
bit to be true (regardless of whether any frames contain transparency), which
is wrong.
Please file a bug on ffmpeg.
Original comment by urv...@google.com
on 30 Sep 2015 at 4:51
Reported the issue on ffmpeg mailing list:
http://ffmpeg.org/pipermail/ffmpeg-devel/2015-October/179955.html
Original comment by urv...@google.com
on 1 Oct 2015 at 8:03
Original issue reported on code.google.com by
tal.lev...@gmail.com
on 30 Sep 2015 at 9:59Attachments: