Twitch VODs not playing from the beginning

[TheLongLife]

mpv Information

mpv v0.38.0-567-g68a1a387 Copyright © 2000-2024 mpv/MPlayer/mplayer2 projects
 built on Jun 29 2024 00:14:16
libplacebo version: v7.349.0 (v7.349.0-rc1-3-g1fd3c7b-dirty)
FFmpeg version: N-116052-gd5e603ddc
FFmpeg library versions:
   libavcodec      61.9.100
   libavdevice     61.2.100
   libavfilter     10.2.102
   libavformat     61.4.100
   libavutil       59.27.100
   libswresample   5.2.100
   libswscale      8.2.100

Other Information

- Windows version: Windows 10 LTSC 1809
- GPU model, driver and version: irrelevant
- Source of mpv: Windows builds by shinchiro
- Introduced in version: n/a

Reproduction Steps

1. Play Twitch VOD (by dragging the link to mpv window, or however you want)
2. Look at the progress bar / current time

Expected Behavior

For video to start playing at the beginning 00:00:00

Actual Behavior

It starts playing roughly a minute after the beginning.

Seeking to beginning manually doesn't work, it just goes back to that same spot.
In VLC it plays from the beginning without issues.

Log File

output.txt

Sample Files

No response

I carefully read all instruction and confirm that I did the following:

• I tested with the latest mpv version to validate that the issue is not already fixed.
• I provided all required information including system and mpv version.
• I produced the log file with the exact same set of files, parameters, and conditions used in "Reproduction Steps", with the addition of --log-file=output.txt.
• I produced the log file while the behaviors described in "Actual Behavior" were actively observed.
• I attached the full, untruncated log file.
• I attached the backtrace in the case of a crash.

[na-na-hi]

mpv v0.38.0-567-g68a1a387 Copyright © 2000-2024 mpv/MPlayer/mplayer2 projects
built on Jun 29 2024 00:14:16

Update. There was a known regression in that range which was fixed.

Edit: still reproducible on current master. The regression had a similar symptom but this might have a different cause.

[Sneakpeakcss]

Had the same issue some time ago and found out that script-opts-add=ytdl_hook-use_manifests=yes fixed this, but at the same time it stopped selecting the very best quality track no matter the ytdl-format setting.

[TheLongLife]

Had the same issue some time ago and found out that script-opts-add=ytdl_hook-use_manifests=yes fixed this, but at the same time it stopped selecting the very best quality track no matter the ytdl-format setting.

Oh that does fix it. Thank you.
It sets the quality to 720p but I can change it to higher resolution within UOSC stream quality menu, no problem.
Actually changing the quality makes the beginning unplayable again xD

[Sneakpeakcss]

Had the same issue some time ago and found out that script-opts-add=ytdl_hook-use_manifests=yes fixed this, but at the same time it stopped selecting the very best quality track no matter the ytdl-format setting.

Oh that does fix it. Thank you. It sets the quality to 720p but I can change it to higher resolution within UOSC stream quality menu, no problem. Actually changing the quality makes the beginning unplayable again xD

Calling it a fix was a bit generous. If you're using mpv-twitch-chat script, then it no longer shifts the subtitle by a minute forward, but if you either reload or progress the video too far, and seek to 00:00 then the issue comes back. To correct the quality i use a lua script + conditional profile:

mp.add_hook("on_preloaded", 50, function ()
    local title = mp.get_property_native("title")
    if title and title:find("Twitch VoD") then
        if mp.get_property("vid") ~= "1" then mp.set_property("vid", "1") end
        if mp.get_property("aid") ~= "1" then mp.set_property("aid", "1") end
    end
end)

[twitchvod]
profile-cond=get("path", ""):find("^https://www.twitch.tv/(.*)videos?") ~= nil
profile-restore=copy
script-opts-add=ytdl_hook-use_manifests=yes
title=Twitch VoD — ${media-title}

From what i remember both vlc and mpc-hc do not have this problem.

[CrendKing]

Thanks. According to my test, both the on_preloaded hook or the auto profile would be too late to change script-opts, because ytdl_hook is already executed on the on_load hook with priority 10. I think an effective script would be something like

mp.add_hook('on_load', 0, function()
    if string.find(mp.get_property_native('stream-open-filename', ''), "^https://www.twitch.tv/videos/") then
        local script_opts = mp.get_property_native('script-opts')
        script_opts['ytdl_hook-use_manifests'] = 'yes'
        mp.set_property_native('script-opts', script_opts)

        -- select the best qualities
        mp.set_property('vid', 1)
        mp.set_property('aid', 1)
    end
end)

[CrendKing]

The reason why the source quality (e.g. 1080p) is not selected by default is probably due to the manifest m3u8 from Twitch declared so. An example extract from such a M3U8:

#EXT-X-MEDIA:TYPE=VIDEO,GROUP-ID="chunked",NAME="1080p60",AUTOSELECT=NO,DEFAULT=NO
#EXT-X-STREAM-INF:BANDWIDTH=4354233,CODECS="avc1.64002A,mp4a.40.2",RESOLUTION=1920x1080,VIDEO="chunked",FRAME-RATE=59.998
...
#EXT-X-MEDIA:TYPE=VIDEO,GROUP-ID="720p60",NAME="720p60",AUTOSELECT=YES,DEFAULT=YES
#EXT-X-STREAM-INF:BANDWIDTH=3433521,CODECS="avc1.4D0020,mp4a.40.2",RESOLUTION=1280x720,VIDEO="720p60",FRAME-RATE=59.998

I still don't know why the non-manifest M3U8 would have the time shift problem at beginning. But assuming it is a inherit problem of the video stream itself, unless mpv is willing to implement a Twitch-specific track selection logic, I don't think there is much mpv can do. We can only hope that one day Twitch would make the 1080p quality from the manifest default.

[Rochkiller]

I saw the solution in another issue, you need to add --demuxer-lavf-o=live_start_index=0 to your command
Mine look like that : & $Mpv $Url --demuxer-lavf-o=live_start_index=0
I didn't try to add it in my mpv.conf but try this :

[twitchvod]
profile-cond=get("path", ""):find("^https://www.twitch.tv/(.*)videos?") ~= nil
profile-restore=copy
script-opts-add=ytdl_hook-use_manifests=yes
title=Twitch VoD — ${media-title}
demuxer-lavf-o=live_start_index=0

[CrendKing]

--demuxer-lavf-o=live_start_index=0

I believe this is only needed for the VOD that is currently live (which yt-dlp has lengthy discussion at yt-dlp/yt-dlp#13181). The original issue was already solved by script-opts-add=ytdl_hook-use_manifests=yes.

[kasper93]

If you are able to build ffmpeg/mpv you can try #17646 and https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/22610

This fixes VODs of live streams, to allow seeking, this is the "subscribe only" feature on twitch page. Maybe it fixes also those issues described in this issue.

[talchas2]

That replaces demuxer-lavf-o=live_start_index=0 and does the job for that better, in that it has the whole stream available for seeking immediately (it does still have the default starting point be the end, but if you didn't want that you can specify start=0 for a twitch profile). You still need script-opts-add=ytdl_hook-use_manifests=yes; vid=1; aid=1.