LG WebOS Plex app BUG + 4K hevc HDR > 1080p VS Samsung APP no bug

[amrlotus]

Server Version#:1.14.1.5488
Player Version#: 3.88.0 webOs 4.1

TV LG Oled 65 C8 2018 Model
SoundBAR Focal

Any Movie I play that has SRT the video gets transcoded to 1080p and Picture losses Vivid color !!!

Same movie played with Xplay HDR and picture is perfect and not transcoded not even the sound but that is not the issue I know Xplay handle sound differently but PLEX team solve this issue this is really very awkward I found more than one person complaining about this and not feedback from plex team

after some testing I discovered that when selecting SRT subtitle this happens 4k is transcode to 1080p !!! what is this bizarre behaviors
even when I used option in plex app on LG settings video > burn subtitles for image formats or always !! still did not work 4k gets transcoded to 1080p !!! what is this

PS srt used in 1080p ok plex app Lg does not transcodes video so why does it need to transcode is 4K

and now I tried the following
1-Converted the Movie from plex universal audio
2-extracted the audio file mkvtool >mka got an ac3 audio track
3-multiplexed the audio track as 1st track in original file

Voila now audio does not transcode and video is in 4 k with srt

PLEX team there seems to be a problem with plex app for LG with this behavior

OH really Plex Team
I did the same thing in another file got different result now AC3 is transcoding audio and video 4k> 720p !!! what is this bizzare behavious the only diff is the AAC audio file is not the first Audio track !!! comeon !!

[pl_5309]

Perhaps you have seen:

[INFO] Plex, 4k, transcoding, and you - aka the rules of 4k

NOTE: for 2022 – Plex has come a long way since this FAQ was originally written, HW transcoding has become more available and more stable, and tone mapping was recently added to address the hdr/sdr color conversion issues. The first 4 ‘rules’ generally are no longer as important as they once were, but may still be a good thing to bear in mind. Dolby Vision, is an entirely other mess. THIS thread/FAQ is NOT about DV. DV work is still in progress, and there are no perfect TV’s or external devic…

When Plex has to convert it prefers to convert to h.264, the combination of the audio and subtitles puts Plex in this situation. The TV is the component that is telling Plex give me stereo so I don’t know if it has settings to pass DTS over ARC to the soundbar.

[gary_parker]

Hey @amrlotus, I’ve got a pair of LG webOS TVs (a 55SK8500PLA and a 55OLEDB8SLC) both running the latest Plex client (3.88.0) and they both stream 4k with SRT subs just fine with no transcoding. One thing I’ve noticed, though, is that the Plex for LG client can be a little inconsistent with the client profile that’s selected for it by PMS. Sometimes I get an error in my logs for “no client profile found” but playback works just fine. Other times it decides to use something like “HTML TV App”, and then it transcodes everything.

I also note that in both your screenshots the DTS track is being transcoded to AAC (and also the AC3 track). This should never be the case on an LG set like yours as it is capable of processing the DTS-HD MA track and passing the DTS core to your soundbar over ARC.

I think you need to make sure that:

• your soundbar is connected to an ARC capable HDMI port on your TV
• you’re using an HDMI 2.0 compatible cable
• you’re connected to an ARC capable socket on your soundbar

…as it looks like the HDMI handshake is wonky.

[amrlotus]

Thanks @gary_parker
Im quiet Sure the Cable is 2.0 HDMI
I think my focal dimension sub does not support DTS-MA or TRUE_HD Atmos (although i just tried it in my sis in law setup she has a ssmung 65" 2018 TV LED not even Qled with the Focal dimension and the funny thing it is not trans coding video or audio )

Focal Dimension Review

but the problem is even if the Soundbar does not support DTS-MA or Atmos and i choose DTS (which is 2nd Audio track it transcodes the video to 1080p as you can c in my images attached)
i was quite happy with Xplay never had those issues (except when Xplay updated to a new UI and messed things up by the devloper who is trying to solve issues with LG bugs as he claims)
and your right there is not Profile for LG TV when i check the LOG
thnaks for the feed back but PLEX should try and solve this you probrably have a sound bar that supports those formats or i think the B8 supports Atmos

Even With SRT Plex client on Samsung Does not Transocde Video !
I think Plex for LG is inferior since the LG C8 OLED has the new A9 processor why would it need to transocde audio in the first place with the same sound bar connected to samsung and also when it transcodes the audio if it should (which it shouldnt ) why would it transocde the 4K video to 1080p ! this is a bug

and this is the same setup with my dimension sound bar
on smasung plex lient with same server synology NAS and same video file
SAMSUNG PLEX CLIENT DOESNT TRANSOCDE !!! COMEON PLEX TEAM

[Morphy]

Dont have any problems what so ever.

Running Plex on LG 65OLEDW8 ( Wall 8 series ) , runs like a warm knife in butter …

The only issue I have, is 7.1 sound will be transcoded, so I just use 5.1. The most important for me is the picture, sound is OK with 5.1

[amrlotus]

Hey @Morphy
My C8 OLED LG is exactly the same procesor as the W8 however
1- 5.1 has to be 1st audio track if it is 2nd audio track then if you choose it it will still transcode regardless this is a bug in plex client for LG (LG requirement)
2-If audio is trans-coded Video is trans-coded as well from 4K > 1080p
my setup has the latest updates for plex and LG
thanks

[gary_parker]

@amrlotus

1- 5.1 has to be 1st audio track if it is 2nd audio track then if you choose it it will still transcode regardless this is a bug in plex client for LG (LG requirement)

Ah, that’s interesting. I always remove the TrueHD tracks from my files (as they’re no use to me) so the first audio track is always one I can play

[gary_parker]

@amrlotus I can confirm that this is not the case, at least with LG Plex client version 3.88.0 and PMS 1.14.1.5488.

I’m currently playing a 4k HDR file with TrueHD as track 1 and AC3 as track2. I’ve selected the AC3 track and there’s no transcoding going on.

One thing I did notice, though, was that it automatically selects a subtitle track if you choose something other than the default audio track. If that subtitle track is a PGS one you could trigger a transcode because of that…

[amrlotus]

@gary_parker
The only difference in my setup is the sound bar so what I will do is use the speakers of tv and give you feedback
Can you please confirm ur speakers ? Are they the th speakers
Side note Also does pms has your lg profile

[gary_parker]

I have an LG SK85000 and an LG OLEDB8, both with a set of Sony HT-RT5 speakers connected using ARC capable HDMI ports at each end. The speakers themselves are DTS-HD MA capable, but obviously not via ARC.

PMS repeatedly indicates “no client profile found” in the logs throughout playback, which is annoying for a Plex provided client

[Morphy]

@amrlotus
Thats strange - I just use 5.1 and everything is working without any transcoding.

I just choose 5.1 wether is 1st or 2nd, dont have any problems.

What happens if you set your sound standard to 5.1? Still an issue?

[apoffys]

The latest Plex for WebOS is simply incapable of playing 4K HEVC + srt subtitles. It works sometimes, but then it randomly decices to start transcoding while playing. It can direct play just fine for half a movie, then start transcoding. It’s absurd. The previous version was not broken, but you can just forget about playing subtitles with the lastest.

[amrlotus]

@Morphy
Dunno if there is any settings for it
It’s supposed to be 5.1 the speaker is Jm labs dimension
But plex client for Samsung same nas and pms version with the same speaker does not have any of those issues at all in 4k even same movie does not transcode so it’s either the client in lg or lg WebOS I’m sure I read on more than one post that the order of audio track makes a difference in LG

[gary_parker]

Interesting. I must admit I rarely watch anything with subtitles, but I’ll give this a go and see how I get on, just as another test subject…

[gary_parker]

Well, just tried three different movies, all with .srt subtitles. 4k, HDR and with either DTS-HD MA or AC3 audio. I’ve left them running for 10-15 minutes each, paused, restarted, ffwd and rwd and used chapter select. Never transcoded once.

Definitely not a problem with Plex client 3.88.0 on LG sets with latest webOS and latest PMS in my situation ¯_(ツ)_/¯

[apoffys]

It happens every time on Plex client 3.88.0 on LG C8 here. I just tested, and it happened after roughly 20 minutes playback on a random point in the movie.

What you see in the pictures is what happens when it starts buffering, and it only happens when using subtitles. I’ll attach the logs as well. Playback started around 15.08.

Plex Media Server.log (3.0 MB)

[gary_parker]

Well, that’s just plain damn weird! As I mentioned previously: I wonder if this has to do with the client profile error we’re getting with Plex for LG at the moment?

I’ve got a mod looking at my logs for that issue here:

“Unable to find client profile” errors on LG Smart TVs, Long Pause Before Playback

Server Version#: 1.14.1.5488, on QNAP Player Version#: Plex for LG 3.86.1 “Unable to find client profile for device; platform=webOS, platformVersion=4.1.0, device=, model=OLED55B8SLC” Also seeing on a LG 55SK8500PLA. Video takes a long time (30s or more) to buffer then eventually starts playing. Error message repeats every 10 seconds throughout playback. Also seeing this streaming from my other server running 1.15.0.659 on Synology.

[apoffys]

I believe i identified the point of failure here:

Feb 26, 2019 15:28:20.500 [8432] DEBUG - MDE: Selected protocol hls; container: mpegts
Feb 26, 2019 15:28:20.500 [8432] DEBUG - MDE: analyzing media item 20383
Feb 26, 2019 15:28:20.500 [8432] DEBUG - MDE: Bohemian Rhapsody (2018): Direct Play is disabled
Feb 26, 2019 15:28:20.500 [8432] DEBUG - MDE: Bohemian Rhapsody (2018): media must be transcoded in order to use the hls protocol
Feb 26, 2019 15:28:20.500 [8432] DEBUG - MDE: Bohemian Rhapsody (2018): selected audio stream is not the first audio stream and direct play stream selection is not enabled
Feb 26, 2019 15:28:20.500 [8432] DEBUG - MDE: Bohemian Rhapsody (2018): selected subtitle cannot be converted to a compatible format, burning into video stream
Feb 26, 2019 15:28:20.500 [8432] DEBUG - MDE: Bohemian Rhapsody (2018): avoiding video remux due to burned subtitle stream
Feb 26, 2019 15:28:20.500 [8432] DEBUG - MDE: Bohemian Rhapsody (2018): no remuxable profile found, so video stream will be transcoded
Feb 26, 2019 15:28:20.500 [8432] DEBUG - MDE: Cannot direct stream video stream due to profile or setting limitations
Feb 26, 2019 15:28:20.500 [8432] DEBUG - Scaled up video bitrate to 190656Kbps based on 4.500000x fudge factor.
Feb 26, 2019 15:28:20.500 [8432] DEBUG - Scaled maximum bitrate for resolution reduction to 47664Kbps.
Feb 26, 2019 15:28:20.500 [8432] DEBUG - MDE: Bohemian Rhapsody (2018): selected media 0 / 20383
Feb 26, 2019 15:28:20.500 [8432] DEBUG - Streaming Resource: Session 0xe7693b8:ys9iu5eg5bqlcuhih0klao88 changed transcode slot usage to used.  Used slots is now 1
Feb 26, 2019 15:28:20.500 [2832] DEBUG - Killing job.
Feb 26, 2019 15:28:20.500 [2832] DEBUG - Job was already killed, not killing again.
Feb 26, 2019 15:28:20.500 [2832] DEBUG - Stopping transcode session p8m9zu79xyvqxujabyucf9v0
Feb 26, 2019 15:28:20.500 [8432] DEBUG - Streaming Resource: Reached Decision id=17311 codes=(General=1001,Direct play not available; Conversion OK. Direct Play=3000,App cannot direct play this item. Direct play is disabled. Transcode=1001,Direct play not available; Conversion OK.) media=(id=20383 part=(id=20886 decision=transcode container=mpegts protocol=hls streams=(Video=(id=53356 decision=transcode bitrate=47664 encoder=libx264 width=1920 height=1080) Audio=(id=53358 decision=copy channels=6 rate=48000) Subtitle=(id=53382 decision=burn languageCode=eng location=embedded))))

I’m no expert in reading these logs though.

edit: After reading the logs a bit more thoroughly, it looks like the client disconnected and reconnected to the server while playing, and then decided to use the first subtitle track instead of the selected track, which is an embedded PGS subtitle. PGS subtitles don’t support direct play, so it starts buffering.

That explains why it’s hard to reproduce and why it only happens some times. It only happens when the network is a bit spotty.

[gary_parker]

Nice spot! The client doesn’t seem to be resuming gracefully with the same settings as before the disconnect, does it? It obviously knows what file is being played, and where it was, but some of the state data is lost regarding audio and subs

[amrlotus]

@gary_parker
on LG c8
1- i chose sound from internal tv (same thing buffering and trnscode pics 720p !
2i turned off dolby atmos and chosed arc output
now only when i chose atmos sound travk i get transcoding in audio that forces video transcode from 4k >1080p
!!!