[FFmpeg-devel] [PATCH] Fix visual glitch with XvMC, caused by wrong idct permutation.

Ivan Kalvachev ikalvachev at gmail.com
Mon Oct 9 01:52:33 EEST 2017

In the past XvMC forced simple_idct since
it was using FF_IDCT_PERM_NONE.
However now we have SIMD variants of simple_idct that
are using FF_IDCT_PERM_TRANSPOSE and if they are selected
XvMC would get coefficients in the wrong order.

The patch creates new FF_IDCT_NONE that
is used only for this kind of hardware decoding
and that fallbacks to the old C only simple idct.

If you have idea for a better name, tell me, I might change it.
I thought of FF_IDCT_HWACCEL_PASSTHROUGHT but it is too huge and ugly.
For some reason mpeg12 vdpau also uses the same idct, so using XVMC in
the name doesn't seem right. (I'm not sure why vdpau needs it...)

I also was thinking of using "-1" number for the define, but ...
I didn't want to risk with it.

Best Regards
   Ivan Kalvachev.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: 0001-Fix-visual-glitch-with-XvMC-caused-by-wrong-idct-per.patch
Type: text/x-patch
Size: 2398 bytes
Desc: not available
URL: <http://ffmpeg.org/pipermail/ffmpeg-devel/attachments/20171009/6ed2d677/attachment.bin>

More information about the ffmpeg-devel mailing list