Convert transparent MOV file to a file that can be used across browsers

[jackkemm]

Hi there, I'm hoping someone can help me as I have tried a few things but no luck!

I have a transparent MOV file (30FPS and 1920x1080) which I want to be able to scroll through on a webpage. I have used a service called "Rotato" to convert this MOV to a transparent MP4 file for Safari, and a WEBM file for Chrome/Firefox.

I have ran the WEBM through FFmpeg using the below command to make sure it can be scrubbed smoothly - it works fine for Firefox, but in Chrome, the video is choppy/doesn't scrub at certain points:

ffmpeg -c:v libvpx-vp9 -i test.webm -movflags faststart -crf 30 -b:v 0 -c:a libvorbis -g 1 -pix_fmt yuva420p -vf scale=1280:-1 test-output.webm

Does anyone know of any other settings that might help with the "judderyness", or has anyone dealt with scenarios like this before? I would massively appreciate the help!

Thanks in advance.

Jack

[Bernix]

No one has responded, so I'll try to give my opinion, which may be all wrong. But I think it's a chrome problem. They have always had a problem with the VP9 codec.