vulkan video decoding: av1 (yes av1) status update
Needless to say h264/5 weren't my real goals in life for video decoding. Lynne and myself decided to see what we could do to drive AV1 decode forward by creating our own extensions called VK_MESA_video_decode_av1. This is a radv only extension so far, and may expose some peculiarities of AMD hardware/firmware.
Lynne's blog entry has all the gory details, so go read that first. (really read it first).
Now that you've read and understood all that, I'll just rant here a bit. Figuring out the DPB management and hw frame ref and curr_pic_idx fields was a bit of a nightmare. I spent a few days hacking up a lot of wrong things before landing on the thing we agreed was the least wrong which was having the ffmpeg code allocate a frame index in the same fashion as the vaapi radeon implementation did. I had another hacky solution that involved overloading the slotIndex value to mean something that wasn't DPB slot index, but it wasn't really any better. I think there may be something about the hw I don't understand so hopefully we can achieve clarity later.