AlphaChannel Videos Export and FFMPEG Profiles (OBS Stinger Compatible)???



i try to export my animation as an video file that preserve the alpha channel webm(vp8/vp9) or mov for an obs trigger video directly.

But it does not work. What must i do.

My second Idea was to export the alpha channel as an extra video an use ffmpeg to make an .webm file with yuv402p, to bring together the normal video an the alpha channel video. Knows anybody the correct ffmpeg params for this situation, when synfig cannot export webm alpha channel videos?

How can i setup an new ffmpeg profile for synfig? Hopefully to combine the output yuv402p to webm, when synfig deliver correctly the raw frames with an alpha channel:
fmpeg.exe -c:v libvpx-vp9 -b:v 2M -vf “format=yuva420p” test.webm



ffmpeg -i ... -b 2M -vcodec libvpx -acodec libvorbis -ab 160000 -f webm -g 30 test.webm