This meta is primarily for internal use in GStreamer elements to support
VP8/VP9 transparent video stored into WebM or Matroska containers, or
transparent static AV1 images. Nothing prevents you from using this meta
for custom purposes, but it generally can't be used to easily to add support
for alpha channels to CODECs or formats that don't support that out of the
box.
This meta is primarily for internal use in GStreamer elements to support VP8/VP9 transparent video stored into WebM or Matroska containers, or transparent static AV1 images. Nothing prevents you from using this meta for custom purposes, but it generally can't be used to easily to add support for alpha channels to CODECs or formats that don't support that out of the box.