Throttling Not Happening

[Neminem 1630]

Tdarr can monitor libraries and automate it

[specy 0]

Any update? Can we have an ETA On the fix please?

[derfy79 4]

@Luke@sa2000

 

Hello, as I would really appreciate it if you could fix this bug, I've set up a test environment to properly diagnose the problem.

Unraid server 7.2.3 with official 4.9.3 Emby Docker with hardware transcoding enabled.

What happens when I have a problematic file is that after a few minutes of playback (2 or 3), the video pauses for 1 second and then resumes... this happens repeatedly.

I have a file with 3 different subtitles (SUBRIP).

I've noticed that only one of the subtitle files is problematic. The one called "forced." If I extract it from the MKV file, I no longer have the problem; if I don't select it when playing the video, I don't have the problem. But I'm still seeing some strange things in the logs.

Another observation: if I use Emby Web with Chrome or Edge, it doesn't seem to have any problems either. Even though I'm still seeing some strange things in the logs.

If I install Diagnostic Option Plugins and enable "Disable HLS subtitles," I don't have any problems.

If you'd like me to provide you with logs and/or run some tests, I can do that for you. Thank you.

[visproduction 338]

Here is a guess.

Subrip is graphic based subtitles and if there no subtitles in the first few minutes, perhaps estimating the transcoding seems fine and begins, but when the graphic subtitles hit, the hardware cannot handle the transcoding in real time at the current transcoding settings.  There is no way for Emby to predict that several minutes into the media, the transcoding settings will take longer than in real time and so the transcoding will buffer and stall.

This would fit all the symptoms, I read.  Maybe I missed something.

Can anyone else recreated the problem? 

I made a case in an earlier post, that this is a file mangement issue.  If an admin wants to transcode, easily without any stuttering, then add hardware or support encoders cards to handle the resolution, even when a subrip graphic subititle starts 3 minutes into a media, or, lower the resolution transcoding settings.  Trying to get Emby to analyze an entire media length, prior to transcoding, is not a good solution.  If this was setup, it would probably fail to work well, cause delays for any user who leaves it switched on and make people think that Emby is broken.   WIth better hardware or transcoding settings, even the tough subrip might work fine.  At most, I would suggest just to have an analzye test that goes further into the media and helps a user find the best transcoding settings and not make this feature into anythng automatic.

If several people can see this issue then maybe adjust Emby to look a little further into the media to test for transcoding. I don't think there is anything to fix, if it only happens to one setup.

 

Edited 2 hours ago by visproduction

[derfy79 4]

I'm not the only one in this situation... and I don't think my hardware is the problem either... this problem didn't occur with version 4.7 and below of Emby.

[donniedarko83 6]

I am in the same boat but no one really cares. I have made a thread with the exact same issue years ago. Just disappointing 

[visproduction 338]

Aha... OK. That subrip graphic does force, a full video transcoding, I believe, in order to burn in the subtitles.  So, starting perhaps with no transcoding is needed and then the first subtitle appears and forces a transcoding. that could fit the symptoms.  Maybe the orced subrip title is no longer noticed in the media and that fools the test and transcoding is not started at all or at some higher quality setting that just fails when the subs finally show up, three mnutes in, or whatever.
Maybe the fix is to make sure Emby notices subrip forced graphic sub in the media metadata. 

Also an issue would be that some metadata for some media does not have all the data at the beginning of the media file. This is the optimized way to have media for streaming, but who knows where the media was created and by what software.  If it is not optimized with the metadata available at th start of the file, then the forced sub info can be missed.  This can happen when anyone makes a copy with a 3rd party software encoder. You cannot easily tell from one media to another if the data is optimized.  That is an issue that is not the fault of Emby, if that is what's happening.

 

Edited 1 hour ago by visproduction

[derfy79 4]

If I watch the same video without transcoding, with the problematic subtitle enabled, everything works fine.

[visproduction 338]

Der,
Transcoding starts based on the end use's bandwidth.  What do you mean watch without transcoding?  Are you using a different player.  Is this local verus remote?  Is it with a different TV or connection?

Some end user player app or browser can play video directly and some cannot?  Transcoding clicks on when the end user needs it.  So, one user can get direct and the another with a different setup cannot and has to have transcoding. Maybe something like that is happening.

 

 

Edited 1 hour ago by visproduction

[derfy79 4]

yes it's local vs remote playback.... this is the reason of trancoding : TranscodeReasons=ContainerBitrateExceedsLimit 

[Lessaj 486]

1 hour ago, visproduction said:

Subrip is graphic based subtitles

Incorrect, it's an SRT embedded in the MKV, so it's just text.