New AV1 video codec

2022-10-31T01:10:59Z

When I render videos I most of the time have the problem that I need to choose between good quality but huge size (5GB for a 6 minutes video) or bad quality but reasonable size (190MB for a 6 minutes video). Even increasing the encoding time did never help to get something in between.

On Friday I started doing some research and found the AV1 codec which promised much smaller sizes while keeping the quality. In the documentation I was looking at it didn't say anything about the speed.

I started trans coding one video and it was incredibly slow, the speed was at 0.1 x. First I didn't realize it and waited one hour but then it was closing in on 2 hours and I checked how many frames there were: 30 fps * 60 sec * 6 min = 108000 frames

I realized that this would take a long time. But then the weekend started and I didn't have anything to do on the computer so it didn't bother me and I actually forgot about it, because I already published that video.

I just opened my computer this morning and saw that it was done encoding. I checked the video size and something was wrong, it was only 70 MB, so I almost deleted it because I assumed the quality would be unwatchable, but just before that I had a quick look and to my extreme surprise, the quality was almost indistinguishable from the original!

Codec | Quality (1-10) | Time to encode | Size
H.265 | 8 | 1h | 4300 MB
AV1 | 7 | 3 days | 70 MB
H.264 | 4 | 2h | 190 MB

I always was dissatisfied with the sharpness of the videos I made. In this example it is especially very visible with the hair or the structure of the fabric of the shirt.

Now 3 days of encoding for 6 minutes of video is obviously not really meaningful when you want to post the video as soon as you have created it. But If you could upload the really good version which has a huge size and then people could already watch it like that, but in the background it would start encoding that video to cut the size to 1/60th and practically keep the quality for archiving purposes, that might make a lot of sense.

The only practical problem I still have with this is that PeerTube does not allow to replace the video file while keeping all the comments/views/URL. There is theoretically a solution for that but it never worked for me in practice.