Encoding Discussion Megathread (ffmpeg, Handbrake, AV1, etc...)

[manu98]

I have an issue with my ffmpeg command.
When using preset 5, I am unable to seek through the movie in jellyfin. It only shows 5 seconds in length, which extends while playing.

But when using preset 6 or higher, the movie plays perfectly fine.
Here is the command:

Code:

ffmpeg -i in.mkv -map 0 -c:s copy -c:v libsvtav1 -pix_fmt yuv420p10le -svtav1-params tune=0:irefresh-type=2:enable-overlays=1:scd=1 -g 240 -movflags +faststart -preset 5  -ac 6 -c:a libopus -b:a 256k -crf 30 out.mkv

I tried both jellyfin-ffmpeg and the latest build from github.
Does anyone have suggestions? I would be very thankful.

Okay, so a few things (and I do the same thing since I don't trust a lot of software to do what it says).

• irefresh-type=2 is unnecessary as that's the default
  
• there's no reason to turn on enable overlays if you're not inserting images as an overlay on top of the video
  
• my guess is that this has to do with your keyframe setting, which looks like it's set at ~10 seconds for standard film frame rate (~24 FPS)
  

Now in my experience, libsvtav1 actually does a pretty good job at figuring out where to put keyframes and you don't really get any compression advantage by moving them further apart. So I might honestly try without the manual keyframe setting and re-encode. It may be that more keyframes are helpful with a larger amount of data between the two -- I know my encodes at 5 and 4 were a few hundred MB difference in size at 1080p and 1+ GB difference in size at 4K depending on bitrate/CRF. Revised?

Code:

ffmpeg -i in.mkv -map 0 -c:v libsvtav1 -preset 5 -crf 30 -pix_fmt yuv420p10le -svtav1-params tune=0:scd=1 -movflags +faststart -c:a libopus -ac 6 -b:a 256k -c:s copy out.mkv

I moved things around because uh...I'm a little OCD about grouping like with like as far as flags go...makes for easier debugging.

Thanks for your answer. Unfortunately, removing the keyframe option does not help.
I did not use it originally, but it was one of many things I tried out.

Do you have any other suggestions?