Creating transparent webm video from TRANSPARENT png image sequence (Can be used for OBS Transition Stingers)

ffmpeg -framerate 60 -f image2 -i %04d.png -c:v libvpx-vp9 -pix_fmt yuva420p output_name.webm

Check if video is actually transparent

  1. Go to chrome/chromium based browser
  2. Drag video to browser window
  3. Change HTML background by adding this in <body>:

Should look like:

<body style="background-color:#FF0000;">

Transparent WebM Test.gif
Transparent WebM Test.mp4

Make Twitter Video's Audio work (usually breaks when using avidemuxe or merging video and audio using ffmpeg)

ffmpeg -i input.mp4 -c:v libx264 -crf 22 -c:a aac -b:a 128k output.mp4