Samsung UE65KS7590 - "An Error has Occured"

[dbmaxpayne]

Hi everyone,

First of all, thanks for the development effort of Universal Media Server.
I have been using it for almost 10 years now as a quiet reader of this forum.

However, I have so far only used it for content that was natively supported on my TV.
Lately I have a lot of content that's video codec is in AV1.
UMS is trying to encode this, but my TV always says "An Error has Occured".
I have so far tried the Linux and Windows version of UMS to no avail.
The only TranscodeVideo setting that works is "HLS-MPEGTS-H264-AC3".
However, I get micro audio gaps and the audio drifts complete out of sync after ~ 30 seconds.

The renderer used is Samsung-UHD.conf in its default configuration.

In the debug log I see that ffmpeg is started and outputs frames to the pipe, but something seems to be broken here.

Any ideas?

Cheers,
Mark

ums_dbg_2023-08-02-18-57.zip

(341.1 KiB) Downloaded 233 times

[mik_s]

I think this may be a limitation of your computer not being able to keep up with transcoding.

I know little about this but from what I can tell AV1 takes a lot of CPU processing to decode which may not leave enough to transcode quick enough so your TV is waiting too long and times out with an error. I know that some graphics cards can do this in hardware so if you have one you can enable hardware decoding and encoding in the transcoding settings.

From the file you played in the logs it is not AV1 but VP9. The specs of the TV actually says that it does support this format.
The only mention for VP9 in the conf is for webm videos so may not be supported in MKVs.

Try playing it from the #--TRANSCODE--# folder and choose "No transcoding"
(if you do not see it, enable "show the #--Transcode--# folder" in the GUI on the navigation tab, in the web GUI it is in the "virtual folders/files" section)
If your TV plays it fine then I can tweak the conf for you so UMS knows not to transcode those.


Its interesting that the only option that did work was the HLS one as I did not think Samsung TVs supported that.

[dbmaxpayne]

Hi mik_s,

Thanks for your reply.

Sorry, that file is indeed VP9. I merely chose it, because I found it funny (and it also doesn't transcode).
The lyrics of the song literally say "why can't my smart TV just do what it's told" xD

Other H265 videos work without transcoding by the way. Not sure why VP9 doesn't work. Maybe it's indeed because of the container.
Either way, no encoding works independent of the source's codec and the speed shouldn't be a problem as I took the ffmpeg command from the logs and replaced its output to the pipe with a normal file.
The encoding speed was around 100 fps.
On my Linux system it's even higher.
The same can be seen in the debug log:

Code: Select all

DEBUG 2023-08-02 18:56:41.358 [ffmpeg.exe-17-2] net.pms.io.OutputTextLogger frame=  246 fps= 97 q=20.0 size=    4437kB time=00:00:10.93 bitrate=3322.7kbits/s speed=4.32x

If at least the audio wouldn't drift when using HLS, I'd be happy.

Do you know if it's possible to get more error information from the TV?
If I use the "No transcoding" option, I don't get the "an error has occured", but an "This format is currently not supported" message.
So I wonder what the actual error is.

[mik_s]

I don't think there is anyway of getting error information unless you hack the TV and see its logs.

I think that confirms that VP9 only works in the webm container so the conf is correct at least.

So something must be wrong with the transcoding settings. Unfortunately I cannot help much there as I have no way of testing so you will have to try experimenting with the setting to see what does work for you. Look at the defaultrenderer.conf as it documents what each setting does.

You could also try to force transcoding of videos that are supported by using the #--TRANSCODE--# folder to see how they play. This would confirm that the transcoding settings are the problem if now other videos start doing the same. It may be that the time it takes UMS to start as it build up a buffer keeps the TV waiting longer than expected, but would work if starts receiving data faster. Try looking for options around transcode fast start. I have had videos give this error on my PS4 when they had loads of subs and took longer for the transcoding to start, sometimes stopping the video after a few seconds of waiting then playing it again immediately would make it work.

Other options that may help are ChunkedTransfer and TranscodedVideoFileSize.

I'm not sure if the transcoding speed is the issue. For HLS from what I understand it breaks down the video into tiny chunks and makes a playlist of them all and this is sent to the renderer. When a chunk is requested then that one is transcoded and sent to the renderer. A lot of chunks are constantly being requested so this process can be split over several cores. If for some reason there is a bottleneck it could affect how things are synced. That is about all I know and may not be correct. I just know that my system is too old to work properly with HLS too.