[FFmpeg-devel] FFV1 specification: plane_count prior to version 4
jerome at mediaarea.net
Sat May 2 02:41:33 CEST 2015
Le 02/05/2015 01:37, Michael Niedermayer a écrit :
> plane_count was 2 for gray prior to version 4 [...]
Maybe I missed something else, but looks like decode_plane() is never
called with plane_index = 1 if chroma_planes is 0.
Was it an implementation bug and actually plane_index = 1 is never used
in the case of gray?
Additionally, I read this code:
> if (fs->transparency)
> decode_plane(fs, p->data + ps*x + y*p->linesize,
width, height, p->linesize, 2);
plane_index is 2 for the alpha plane if transparency is 1, in all cases.
but I understood that for version >= 4, plane_count is 2 if grey+alpha,
so plane_index = 2 would not be possible.
shouldn't it be
decode_plane(fs, p->data + ps*x + y*p->linesize,
width, height, p->linesize, (f->version >= 4 && !f->chroma_planes) ?
1 : 2);
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