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+--- Thread: LG WebOS Dolby Vision playback on v10.9.x (/t-lg-webos-dolby-vision-playback-on-v10-9-x)
LG WebOS Dolby Vision playback on v10.9.x - Ereb_Zx - 2024-06-01
Remuxing DV has been my favorite feature of v10.9, it works well but there are some issues. I'm using LG C2 with the latest version of Jellyfin installed from LG Store and server v10.9.3.
As we know, LG TVs can play Dolby Vision Profile 5 and 8 files if the container is .mp4, .ts or .m2ts. Since v10.9 all .mkv files containing DV get remuxed so TV could play without transcoding or falling back to HDR.
Most of my issues are regarding the option Prefer fMP4-HLS Media Container being enabled by default. Issues I have noticed are:
1. Being unable to seek more than 2-3 minutes at the time. Seeking more than that causes the player to start loading indefinitely.
2. Being unable to resume playback. If I play a movie from Continue Watching section that I have watched half way through, playback never starts, player loads indefinitely.
3. Disregarding the audio delay when remuxing .mkv file that has delayed audio (example image below). Audio and video play out of sync, ignoring the delay.
Disabling Prefer fMP4-HLS Media Container option fixes those issues. Insted of remuxing .mkv files to .mp4, they get remuxed to .ts which still triggers Dolby Vision playback on LG C2 for both Profile 5 and Profile 8, without those 3 issues I have when using fmp4. Seeking and resuming work perfectly, while audio delay from .mkv file is respected so audio and video are in sync. However, it isn't a perfect solution because it introduces an issue with external .srt subtitles being out of sync after seeking, which is an old known issue.
So for me, it is pick and choose which to use, depending on the situation, but I personally don't understand why is the option to use fmp4 enabled by default, since it introduces more issues than using .ts container.
One more thing I have noticed is that .m2ts files containing DV also get remuxed to either .mp4 or .ts depending on the setting, which is unnecessary since my TV is able to direct play .m2ts files with DV, both Profile 5 and 8. It used to be like that back in 10.8 and I think it should be reverted.
Those are all the observations I have so far since I updated to 10.9. Thank you for this great feature which saves me so much storage space not having to convert .mkv to .mp4 manually. I hope it gets all sorted out, it's almost there.
RE: LG WebOS Dolby Vision playback on v10.9.x - TheDreadPirate - 2024-06-01
The reason that the default was to enable fMP4 is for AV1 support. TS does not support AV1.
It is definitely a trade off.
If everyone would just support MKV properly we wouldn't have this issue. MKV is open source for crying out loud.
