Jorge Estrada (HE12025-08-06): > This patch adds the alphamerge_cuda video filter
Thanks, but sorry, no: this is wrong, although not by your fault. Your filter supports only planar formats. Changing a whole plane in a planar format should involve a little reference counting gymnastics and updating a pointer, no data copy. See <https://code.ffmpeg.org/FFmpeg/FFmpeg/issues/20153>: # `vf_alphamerge` was added in July 2012 (82ecae8a70), it used memcpy() to # replace the alpha plane of the frame, that was later (d6b9f2b7da) # updated to use av_image_copy_plane(). # # But in March 2013 (c4e8821732), we gained the ability to share plane # data between multiple frames, thanks to refcounted buffers. # `vf_alphamerge` could have used that ability, but it was never done, # probably because `vf_alphamerge` came from the FFmpeg side while the # refcounting came from the libav side. # # `vf_alphamerge` needs to be updated to only create a new reference to # the alpha plane of the input frame and use it in the output frame. No # data copy involved at all. The same probably applies to vf_extractplanes.c, although the excuse of having been added before refcounting is not valid for this one. These are rather low-hanging fruits. Regards, -- Nicolas George _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
