How can I avoid transcoding Live TV?

[jonm]

I'm using tvheadend for live TV. In JMP it works fine without transcoding, however when I watch TV using the Tizen app on my TV, it always transcodes and the dashboard tells me: 

The media is being converted into a format that is compatible with the device that is playing the media. 
Framerate: 50fps
119.7Mbps TS H264 AAC
Reason for transcoding
The container is not supported

Is there something I can change to stop this transcoding happening?

Note: server version 10.9.4 and latest Tizen client.

[TheDreadPirate]

Is it transcoding or remuxing? The ffmpeg log would tell us that. I'm assuming if only the container is not supported it is just remuxing. What container is tvheadend streaming? TS? HLS/fMP4? MKV?

[jonm]

Here's what I believe to be the relevant bit from the ffmpeg log: 

Code:

Input #0, mpegts, from 'http://192.168.2.8:9981/stream/channelid/1956604891?ticket=f6eb529a9305f71fcbbcb4fd1c5504255d3267fe':
  Duration: N/A, start: 92933.151733, bitrate: N/A
  Program 1
    Metadata:
      service_name    : SRF info HD
      service_provider: Schweizer Radio und Fernsehen
  Stream #0:1[0x20a]: Video: h264 (High) ([27][0][0][0] / 0x001B), yuv420p(progressive), 1280x720 [SAR 1:1 DAR 16:9], 50 fps, 50 tbr, 90k tbn
  Stream #0:2[0x20b](deu): Audio: mp2 ([3][0][0][0] / 0x0003), 48000 Hz, stereo, fltp, 192 kb/s
  Stream #0:3[0x20c](eng): Audio: mp2 ([3][0][0][0] / 0x0003), 48000 Hz, stereo, fltp, 192 kb/s
  Stream #0:4[0x20d](deu): Audio: ac3 ([6][0][0][0] / 0x0006), 48000 Hz, stereo, fltp, 192 kb/s
  Stream #0:5[0x20f](deu,deu): Subtitle: dvb_teletext ([6][0][0][0] / 0x0006), 492x250
  No Program
  Stream #0:0[0x12]: Data: epg
Stream mapping:
  Stream #0:1 -> #0:0 (h264 (native) -> h264 (libx264))
  Stream #0:2 -> #0:1 (mp2 (native) -> aac (native))
Press [q] to stop, [?] for help
[libx264 @ 0x55e3f442c0c0] using SAR=1/1
[libx264 @ 0x55e3f442c0c0] using cpu capabilities: MMX2 SSE2Fast LZCNT SSSE3 SSE4.2 AVX
[libx264 @ 0x55e3f442c0c0] profile Main, level 5.1, 4:2:0, 8-bit
Output #0, hls, to '/var/cache/jellyfin/transcodes/fab33ec6e5c55d82319452bf790bde41.m3u8':
  Metadata:
    encoder        : Lavf60.16.100
  Stream #0:0: Video: h264, yuv420p(bt709, progressive), 1280x720 [SAR 1:1 DAR 16:9], q=2-31, 50 fps, 90k tbn
    Metadata:
      encoder        : Lavc60.31.102 libx264
    Side data:
      cpb: bitrate max/min/avg: 119360000/0/0 buffer size: 238720000 vbv_delay: N/A
  Stream #0:1: Audio: aac (LC), 48000 Hz, 5.1, fltp, 384 kb/s
    Metadata:
      encoder        : Lavc60.31.102 aac
frame=    0 fps=0.0 q=0.0 size=N/A time=00:00:00.00 bitrate=N/A speed=  0x
frame=  58 fps=0.0 q=22.0 size=N/A time=00:00:01.30 bitrate=N/A speed=2.29x
frame=  117 fps=109 q=24.0 size=N/A time=00:00:02.36 bitrate=N/A speed= 2.2x
frame=  177 fps=112 q=23.0 size=N/A time=00:00:03.66 bitrate=N/A speed=2.31x
[hls @ 0x55e3f40edc00] Opening '/var/cache/jellyfin/transcodes/fab33ec6e5c55d82319452bf790bde410.ts' for writing
[hls @ 0x55e3f40edc00] Opening '/var/cache/jellyfin/transcodes/fab33ec6e5c55d82319452bf790bde41.m3u8.tmp' for writing

[TheDreadPirate]

Yep.  Its transcoding.

In Dashboard > Users > Select your user, do you have Force Transcoding of live TV checked?

   

[jonm]

I just checked and I can confirm that "Force transcoding of remote media sources such as Live TV" is *not* checked.

[TheDreadPirate]

Are you using a reverse proxy? If so, is it Nginx?

[jonm]

I'm not using any reverse proxy.

[TheDreadPirate]

OK. So in your opening post the bit rate is 120Mbps. Is that coming into jellyfin? Or going out of Jellyfin? From the ffmpeg log it looks like that is the output bit rate?

[jonm]

So in my opening post that was what the info pop-up told me in the dashboard when I click the "i" on the active device. It sounds really high for a bitrate. I'm looking now at the stats on the tvheadend status page and that is showing between 8000-10000 kb/s i.e. 10Mbits/s which seems more reasonable. So that's the rate of the stream coming from tvheadend into the jellyfin server.

[TheDreadPirate]

I'm probably going to ask you to create a github issue, but I'd like to see your full jellyfin log before doing that. Can you share it via pastebin?