MPV: Set default audio delay when converting to AC3? Also, video config and cache settings (Jellyfin)?

HungL

Novice Member
I've got a few questions but I'll start with most to least bothersome.

Windows 11
mpv-x86_64-20220313-git-7ac4b7d​
Jellyfin MPV Shim (2.0.2)​
AAF Optimus (6.0.9600.2311)​
MSI Z170A M5, ALC-1150​
Onboard SPDIF > Sonos adapter > HDMI > Sonos Beam gen1​

I passthrough AC3 and convert 6ch AAC/EAC3, and the Sonos app correctly shows DD5.1 or Stereo PCM. Yay! AAC/EAC3 conversions consistently show 100ms delay. I strongly suspect that AC3 is also delayed by a few dozen ms. It should technically be passthrough but I don't know what kind of latency I can expect with a hacked Dolby decoder + lavcac3enc + decompressing DD5.1 over SPDIF.

How can set a default delay based on audio codec? Another solution could be a global delay when lavcac3enc is attached since the majority of my content is AAC/EAC3. I don't think file-specific conf or profiles could solve this issue because all my content is streamed from Jellyfin. Maybe profiles could work, but doesn't it only work on file names and directories? Can profiles be triggered by codecs?

mpv.conf:
ao=wasapi​
audio-spdif=ac3,dts​
audio-channels=5.1,stereo​
af=scaletempo2:max-speed=6.73,lavcac3enc=yes:640:6​

---

1660S -> DisplayPort -> Nixeus EDG27v2 (144Hz)
hwdec=nvdec-copy​
profile=gpu-hq​
scale=ewa_lanczossharp​
cscale=ewa_lanczossharp​
video-sync=display-resample​
interpolation=yes​
tscale=oversample​
gpu-api=vulkan​
priority=high​
save-position-on-quit​
keep-open=yes​
cache=yes​

I don't remember what scale/cscale/tscale do but I assume I did it for a reason, maybe good? Can someone give feedback on this video config?

G-SYNC enabled, NVIDIA Control Panel for MPV. Fullscreen, can I have the monitor run the refresh rate at the same framerate as the media? Windowed, I would need it to play well with my desktop environment being 144Hz persistent. Also, I often zoom extra-wide content in fullscreen and would love to hear any suggestions for improving performance or quality in that scenario (or if I'm good as-is).

---

I use Jellyfin 10.8 + MPV Shim. At the end of every episode, the next video won't load unless I watch the very last second. Not sure if this is due to Jellyfin, the MPV Shim. It would be nice if the Prev/Next buttons worked, but I don't know if Jellyfin/MPV Shim can even be configured to work that way. At the least, is there a way to allow the next video to load when I scrub all the way to the end? Is there a way to limit scrubbing so it always stops at the very last second?

Additionally, I would like playback to start as soon as possible and not wait for the cache to fill. I would like a huge cache since this machine (16GB RAM, 8GB VRAM) is on the same local network as the server. I think I have to do something with demuxer-max-bytes? Would appreciate if anyone could save me reading/interperting docs.
 
Last edited:

The latest video from AVForums

Samsung S95B QD-OLED Review - A Quantum Leap for OLED!
Subscribe to our YouTube channel
Support AVForums with Patreon

Top Bottom