>Incompatible pixel format 'yuv440p' for codec 'libvpx-vp9', >auto-selecting format 'yuv420p' >The command used was: ffmpeg -i Video1310.mkv -strict -2 -codec:v vp9 >-profile:v 1 -pix_fmt yuv440p -y test.webm I am not sure what libvpx-vp9 supports but it appears that you entered "yuv440p" instead of "yuv444p" as the pixel format. -Sean