HD Playback problem with YLE-channels only

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nikkolade
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HD Playback problem with YLE-channels only

Post by nikkolade » Fri Mar 19, 2021 6:06 pm

I have this strange issue, where I'm unable to playback normally a DVB-T2 HD broadcast, but the issue only happens on finnish tv broadcaster YLE's HD channels and on this particular host using Samsung 4k TV.

The playback works just fine when watching any other publicly available HD channel, but only YLE's HD channels are being played with the wrong screen size and thus only roughly the 1/4 of the tv screen is visible (upper left corner).

I'm currently using Ubuntu 20.04 with Radeon 5500XT and quite recent git master (0.32) checkout (6911843ed88dddb385f8cdfa584d95975a2b518b).

The "ffmpeg -i" output for this example is the following:

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Input #0, mpegts, from 'hd.problem.20021_20210319155800.ts':
  Duration: 00:32:57.49, start: 25956.727922, bitrate: 6202 kb/s
  Program 1 
    Stream #0:0[0x136]: Video: h264 (Main) ([27][0][0][0] / 0x001B), yuv420p(tv, bt709, top first), 1920x1080 [SAR 1:1 DAR 16:9], 25 fps, 50 tbr, 90k tbn, 50 tbc
    Stream #0:1[0x352](fin): Audio: ac3 (AC-3 / 0x332D4341), 48000 Hz, stereo, fltp, 448 kb/s
    Stream #0:2[0x355](dut): Audio: ac3 (AC-3 / 0x332D4341), 48000 Hz, stereo, fltp, 192 kb/s (visual impaired) (descriptions)
    Stream #0:3[0x467](fin): Subtitle: dvb_subtitle ([6][0][0][0] / 0x0006)
    Stream #0:4[0x468](swe): Subtitle: dvb_subtitle ([6][0][0][0] / 0x0006)
    Stream #0:5[0x13ec](fin): Subtitle: dvb_teletext ([6][0][0][0] / 0x0006)
    Stream #0:6[0x47e](fin): Subtitle: dvb_subtitle ([6][0][0][0] / 0x0006) (hearing impaired)
The mythfrontend log shows the following:

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2021-03-19 19:15:53.261665 I [1697/1697] CoreContext mythvideooutgpu.cpp:79:Create  VidOutGPU: Allowed renderers (filt: ffmpeg): opengl,opengl-yv12
2021-03-19 19:15:53.262690 I [1697/1697] CoreContext mythvideoprofile.cpp:304:MythVideoProfile  VideoProfile: Accepting: cmp() w() h() framerate() codecs( ) dec(ffmpeg) cpus(2) skiploop(enabled) rend(opengl) deint(high,high) upscale(bilinear)
2021-03-19 19:15:53.262697 I [1697/1697] CoreContext mythvideoprofile.cpp:445:LoadBestPreferences  VideoProfile: LoadBestPreferences(640x480, 29.970, h264)
2021-03-19 19:15:53.262702 I [1697/1697] CoreContext mythvideoprofile.cpp:470:LoadBestPreferences  VideoProfile: LoadBestPreferences result: priority:1 width: height: fps: codecs: 
2021-03-19 19:15:53.262706 I [1697/1697] CoreContext mythvideoprofile.cpp:475:LoadBestPreferences  VideoProfile: decoder:ffmpeg renderer:opengl deint0:high deint1:high cpus:2 upscale:bilinear
2021-03-19 19:15:53.262709 I [1697/1697] CoreContext mythvideooutgpu.cpp:93:Create  VidOutGPU: Preferred renderer: opengl
2021-03-19 19:15:53.262711 I [1697/1697] CoreContext mythvideooutgpu.cpp:123:Create  VidOutGPU: Trying video renderer: 'opengl'
2021-03-19 19:15:53.262748 I [1697/1697] CoreContext mythhdrtracker.cpp:37:Create  HDRTracker: HDR signalling support not available
2021-03-19 19:15:53.262767 I [1697/1697] CoreContext mythvideogpu.cpp:33:MythVideoGPU  VideoGPU: Discard stereoscopic fields: Yes
2021-03-19 19:15:53.262773 I [1697/1697] CoreContext opengl/mythopenglvideo.cpp:55:MythOpenGLVideo  GLVid: Chroma upsampling filter disabled
2021-03-19 19:15:53.262778 I [1697/1697] CoreContext opengl/mythpainteropengl.cpp:74:ClearCache  Clearing OpenGL painter cache.
2021-03-19 19:15:53.264263 I [1697/1697] CoreContext mythvideobounds.cpp:122:PopulateGeometry  VideoBounds: Window using screen 'HDMI-A-0' 2560x1440
2021-03-19 19:15:53.264266 I [1697/1697] CoreContext mythvideobounds.cpp:481:PrintMoveResizeDebug  VideoBounds: Window Rect:  2560x1440+0+0
2021-03-19 19:15:53.264268 I [1697/1697] CoreContext mythvideobounds.cpp:484:PrintMoveResizeDebug  VideoBounds: Display Rect: 1920x1440+320+0 Aspect: 1.77778
2021-03-19 19:15:53.264270 I [1697/1697] CoreContext mythvideobounds.cpp:488:PrintMoveResizeDebug  VideoBounds: Video Rect:   640x480+0+0 Aspect: 1.33333
2021-03-19 19:15:53.264274 I [1697/1697] CoreContext mythvideocolourspace.cpp:116:SetSupportedAttributes  ColourSpace: PictureAttributes: Brightness,Contrast,Colour,Hue,Range
2021-03-19 19:15:53.264279 I [1697/1697] CoreContext mythvideooutgpu.cpp:561:InitDisplayMeasurements  VidOutGPU: Display aspect ratio: 1.77778 (Square pixels)
2021-03-19 19:15:53.265740 I [1697/1697] CoreContext videobuffers.cpp:976:CreateBuffers  Created 30 YUV420P (640x480) video buffers
2021-03-19 19:15:53.265747 I [1697/1697] CoreContext mythvideobounds.cpp:601:SetVideoScalingAllowed  VideoBounds: Over/underscan. V: 0.03, H: 0
2021-03-19 19:15:53.265748 I [1697/1697] CoreContext mythvideobounds.cpp:481:PrintMoveResizeDebug  VideoBounds: Window Rect:  2560x1440+0+0
2021-03-19 19:15:53.265749 I [1697/1697] CoreContext mythvideobounds.cpp:484:PrintMoveResizeDebug  VideoBounds: Display Rect: 1920x1440+320+0 Aspect: 1.77778
2021-03-19 19:15:53.265751 I [1697/1697] CoreContext mythvideobounds.cpp:488:PrintMoveResizeDebug  VideoBounds: Video Rect:   640x451+0+17 Aspect: 1.33333
and

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2021-03-19 19:15:53.287299 I [1697/653790] Decoder decoders/avformatdecoder.cpp:1457:InitVideoCodec  AFD: InitVideoCodec ID:H264 Type:Video Size:0x0
2021-03-19 19:15:53.287302 I [1697/653790] Decoder decoders/avformatdecoder.cpp:1556:InitVideoCodec  AFD: InitVideoCodec invalid dimensions, resetting decoder.
2021-03-19 19:15:53.287309 I [1697/653790] Decoder mythplayer.cpp:685:SetFrameInterval  Player(i): SetFrameInterval Interval:33366 Speed:1 Scan:Progressive Scan (Multiplier: 1)
2021-03-19 19:15:53.287319 I [1697/653790] Decoder mythvideooutgpu.cpp:448:InputChanged  VidOutGPU: Video changed: 640x480 (640x480) 'H.264' (Aspect 1.33333 Refs 16)-> 640x480 (640x480) 'H.264' (Aspect 1.33333 Refs 16)
2021-03-19 19:15:53.287327 I [1697/653790] Decoder mythvideoscantracker.cpp:263:DetectInterlace  ScanTracker: DetectInterlace(Detect Scan, Interlaced Scan, 29.97, 480) ->Interlaced Scan
2021-03-19 19:15:53.287334 I [1697/653790] Decoder decoders/avformatdecoder.cpp:2452:ScanStreams  AFD: Using ffmpeg for video decoding
2021-03-19 19:15:53.287586 I [1697/1697] CoreContext platforms/mythscreensaverdbus.cpp:85:Inhibit  ScreenSaverDBus: Successfully inhibited screensaver via org.freedesktop.ScreenSaver. cookie 4202310198. nom nom
2021-03-19 19:15:53.287596 I [1697/653790] Decoder decoders/avformatdecoder.cpp:2533:OpenAVCodec  AFD: Opened codec 0x7fb28c035980, id(H264) type(Video)
2021-03-19 19:15:53.287643 I [1697/1697] CoreContext platforms/mythscreensaverx11.cpp:247:Disable  ScreenSaverX11: Inhibited X11 screensaver
As the Radeon 5500XT is not exactly too powerful with the 4K display, I have been using the X11 resolution of 2550x1440 by default (matters more while using the host for other purposes than mythtv)

Any ideas how to debug more for this issue ?

blm-ubunet
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Re: HD Playback problem with YLE-channels only

Post by blm-ubunet » Thu Mar 25, 2021 2:47 am

What strikes me as odd is the video size is 640x480 and using ffmpeg decoding..

InitVideoCodec AFD: InitVideoCodec ID:H264 Type:Video Size:0x0 ... & resetting decoder is odd..

Do your broadcasters use dvb-t2 for SD feeds ?

Are you using mythfrontend in windowed mode (cmd line opts) or with a specific playback screen size ?

Your video card should eat 4K desktop display for breakfast.. I'm using GTx1050TI and the 5500XT is meant to have 50% more raw performance.
MythTV's UI does slow down a little bit when running at 4K but the video card does not even start the fans with video decode/playback at 4K.

nikkolade
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Re: HD Playback problem with YLE-channels only

Post by nikkolade » Thu Mar 25, 2021 1:47 pm

blm-ubunet wrote:
Thu Mar 25, 2021 2:47 am
What strikes me as odd is the video size is 640x480 and using ffmpeg decoding..

InitVideoCodec AFD: InitVideoCodec ID:H264 Type:Video Size:0x0 ... & resetting decoder is odd..

Do your broadcasters use dvb-t2 for SD feeds ?
No, for some reason, mythfrontend gets this all wrong on this particular 4k TV. The whole channel only sends HD-quality programs
and the very same recorded program can be watched as 1920x1080 on any other linux box or using the older HD-only capable Samsung TV.

blm-ubunet wrote:
Thu Mar 25, 2021 2:47 am
Are you using mythfrontend in windowed mode (cmd line opts) or with a specific playback screen size ?
I am using full-screen for the mythfrontend and although I have propably tested all possible combinations
of the playback screen size options, I'm just running the X11 using the 2560x1440 resolution instead of full 4K
due to radeon 5500XT being too slow with full 4K while playing some games etc.
blm-ubunet wrote:
Thu Mar 25, 2021 2:47 am
Your video card should eat 4K desktop display for breakfast.. I'm using GTx1050TI and the 5500XT is meant to have 50% more raw performance.
MythTV's UI does slow down a little bit when running at 4K but the video card does not even start the fans with video decode/playback at 4K.
Yes, but as this machine is combined MythTV & Living room gaming machine, a resolution of 2560x1440 seems to be a reasonable compromise right now, until more powerfull gpu's are again available for purchase. If mythfrontend would work any better with 4K, I would certainly use higher resolutions, but instead it always chooses to playback these YLE-channel's HD programs with 640x480 for some wierd reason.

Unfortunately, I'm not able to tell if some older trunk version worked any better, as the whole HW setup is completely new.

blm-ubunet
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Re: HD Playback problem with YLE-channels only

Post by blm-ubunet » Sat Mar 27, 2021 9:31 am

Almost looks like a aspect ratio calculation error or that the stream probing does not get the correct video info.

Can you cut 20MB from the beginning of a recording using dd & upload somewhere?
(Be very careful with usage of dd == disk destroyer)

Not to fix this problem but.. Have you tried other video decode options?
VDPAU or other ?
I always found ffmpeg & opengl decode in MythTV to look very bad.

nikkolade
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Re: HD Playback problem with YLE-channels only

Post by nikkolade » Sat Mar 27, 2021 6:11 pm

Here is the link: https://file.re/2021/03/27/hdproblem20m ... 319155800/

I tried again with ffplay and of course it gets completely confused with the video & teletext screens. Mplayer is able to play the clip just fine, though. I can try again with VDPAU, I believe I have tried it earlier without success.

blm-ubunet
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Re: HD Playback problem with YLE-channels only

Post by blm-ubunet » Sat Mar 27, 2021 8:34 pm

The best player is probably mpv.
But I don't see any subtitles (dvb_teletext) using mpv.

Depending on how your MythTV packages were built .. you may have mythffmpeg / mythffplay binaries to try..
Or mythavtest/mythfrontend -v libav,playback:debug

mythffplay plays it okay but displays no subtitles.
I believe MythTV has significantly better subtitle support than ffplay.

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kmdewaal
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Re: HD Playback problem with YLE-channels only

Post by kmdewaal » Sat Mar 27, 2021 9:17 pm

The clip plays OK here, both on a 1920x1080 and on a 3840x2160 screen. This is with the latest master. Have not looked at subtitles.
The comment of bim-ubunet:
What strikes me as odd is the video size is 640x480
is also for me the first item in the log that is really wrong.
Maybe you can post the complete log file generated with

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mythfrontend -v playback --loglevel=debug --logpath=.
doing a complete playback of the clip.

nikkolade
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Re: HD Playback problem with YLE-channels only

Post by nikkolade » Sun Mar 28, 2021 8:57 pm

kmdewaal wrote:
Sat Mar 27, 2021 9:17 pm
The clip plays OK here, both on a 1920x1080 and on a 3840x2160 screen. This is with the latest master. Have not looked at subtitles.
Ok, this is something I did not take into account. If I shorten the problematic recording to a way shorter length (say 20-50MB) the playback problem disappears. Once I revert back to the original test recording (ie. full length) the playback issue is back. Does the .ts file contain some important metadata in the end of the file ?

I have now updated to the currently latest git master (6d429d930ad04ba478a59f31c515764558d8390c) and the problem still exists, but I was wondering if you are more interested about a private link to another shorter clip of 850MB that shows the issue when the recording has not been shortened ? I can of course also run the full debug logs for the full file if that is preferred instead.

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kmdewaal
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Re: HD Playback problem with YLE-channels only

Post by kmdewaal » Sun Mar 28, 2021 9:16 pm

Yes, if you can send me a link to the failing clip that would be great. For me gmail always works OK.
About the ts format, this is literally how TV is transmitted which means you can start and stop watching at any point in time. Just like you can switch your TV on at any moment and switch it off before the end of the program.
What can happen is that the format changes halfway. As I understand the code, MythTV looks at the first few megabytes to decide what the format is and then sticks to that. Possibly your recording starts a few minutes early with a bit of video in a different format, but I can figure that out when I have your clip.
There have been more reports about YLE giving problems.....

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kmdewaal
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Re: HD Playback problem with YLE-channels only

Post by kmdewaal » Mon Mar 29, 2021 10:13 pm

Examining the long YLE video clip sent to me directly.
The problem is that MythTV cannot correctly determine the attributes of the H264 video stream. It then defaults to 640x480 with 29.970fps. At playback then the left/top 640x480 rectangle is cut out of the 1920x1080 video size and this is then expanded to fill the available screen size.

The info from mythffmpeg shows little video information and no image size:

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Input #0, mpegts, from '../ava/videos/yle-2002120210327155800.ts':
  Duration: N/A, bitrate: N/A
    Stream #0:0[0x136]: Video: h264, 1 reference frame, none, 90k tbn
    Stream #0:1[0x352](swe): Audio: ac3 (AC-3 / 0x332D4341), 0 channels
    Stream #0:2[0x355](dut): Audio: ac3 (AC-3 / 0x332D4341), 0 channels
    Stream #0:3[0x467](fin): Subtitle: dvb_subtitle
    Stream #0:4[0x468](swe): Subtitle: dvb_subtitle
    Stream #0:5[0x47f](swe): Subtitle: dvb_subtitle
    Stream #0:6[0x13ec](fin): Subtitle: dvb_teletext
At least one output file must be specified
Comparing this with the info from the real ffmpeg (not the mythffmpeg) shows the full H264 video information:

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Input #0, mpegts, from '../ava/videos/yle-2002120210327155800.ts':
  Duration: 00:21:49.84, start: 49058.512100, bitrate: 5580 kb/s
  Program 1 
    Stream #0:0[0x136]: Video: h264 (Main), 1 reference frame ([27][0][0][0] / 0x001B), yuv420p(tv, bt709, top first, left), 1920x1080 (1920x1088) [SAR 1:1 DAR 16:9], 25 fps, 50 tbr, 90k tbn, 50 tbc
    Stream #0:1[0x352](fin): Audio: ac3 (AC-3 / 0x332D4341), 48000 Hz, stereo, fltp, 448 kb/s
    Stream #0:2[0x467](fin): Subtitle: dvb_subtitle ([6][0][0][0] / 0x0006)
    Stream #0:3[0x47e](fin): Subtitle: dvb_subtitle ([6][0][0][0] / 0x0006) (hearing impaired)
    Stream #0:4[0x13ec](fin): Subtitle: dvb_teletext ([6][0][0][0] / 0x0006)
    Stream #0:5[0x355](dut): Audio: ac3 (AC-3 / 0x332D4341), 0 channels (visual impaired) (descriptions)
    Stream #0:6[0x468](swe): Subtitle: dvb_subtitle ([6][0][0][0] / 0x0006)
    Stream #0:7[0x47f](swe): Subtitle: dvb_subtitle ([6][0][0][0] / 0x0006) (hearing impaired)
At least one output file must be specified
The version of mythffmpeg is:

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[klaas@kasus mma-dev]$ mythffmpeg
ffmpeg version v32-Pre-717-gd0f923b184 Copyright (c) 2000-2020 the FFmpeg developers
The version of the real ffmpeg is:

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[klaas@kasus mma-dev]$ ffmpeg
ffmpeg version 4.3.1 Copyright (c) 2000-2020 the FFmpeg developers
Doing this with the ffmpeg of Ubuntu 18.04 which has this version:

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klaas@myth3 $ ffmpeg
ffmpeg version 3.4.8-0ubuntu0.2 Copyright (c) 2000-2020 the FFmpeg developers
  built with gcc 7 (Ubuntu 7.5.0-3ubuntu1~18.04)
also gives the correct information, identical to what ffmpeg version 4.3.1 gives.

To summarize:
  • the way YLE has coded the transport stream does have issues but VLC and TV's can play it
  • ffmpeg understands the format, both the actual version 4.3.1 and the older 3.4.8
  • the MythTV version of ffmpeg does NOT understand the format.
  • MythTV is built upon the MythTV version of ffmpeg and hence also does NOT understand the format
It could be that the MythTV version of ffmpeg is older than version 3.4.8 and in that case the problem can be fixed by updating the ffmpeg in MythTV.

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paulh
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Re: HD Playback problem with YLE-channels only

Post by paulh » Tue Mar 30, 2021 1:43 pm

The last ffmpeg resync was in July 2020 and should bring us to ffmpeg v4.3.1. Maybe we are missing some updates from 4.3 release branch?
commit 97d020f90d490aa6e219fd3b860eac69e0a44afa
Author: Peter Bennett <pbennett@mythtv.org>
Date: Sun Jul 19 12:05:34 2020 -0400

New version of FFmpeg - FFmpeg 4.3.1

MythTV specific changes have already been merged, using the method in
README.sync

ffmpeg/FFmpeg release/4.3 n4.3.1-4-gd913badb9f
MythTV/FFmpeg release/4.3 n4.3.1-34-gfa0695653c
I should also say problems with YLE channels is nothing new they have always been problematical for the MythTV player. Does mythffplay play OK or does that fail as well?

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Re: HD Playback problem with YLE-channels only

Post by nikkolade » Tue Mar 30, 2021 6:16 pm

paulh wrote:
Tue Mar 30, 2021 1:43 pm
I should also say problems with YLE channels is nothing new they have always been problematical for the MythTV player. Does mythffplay play OK or does that fail as well?
I just tested and while the mythfrontend has issues, the mythffplay seemed to play with full size picture, so there was a big difference.
I had to try this out multiple times and it was always the same results, mythfrontend failed, while mythffplay was able to play with the correct screen size every single time.

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Re: HD Playback problem with YLE-channels only

Post by blm-ubunet » Tue Mar 30, 2021 6:20 pm

I understood the problem to be related to the detection probesize / initial sampling size.
Or the MythTV demuxer does something else that ffmpeg does not.

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kmdewaal
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Re: HD Playback problem with YLE-channels only

Post by kmdewaal » Tue Mar 30, 2021 8:30 pm

I did some test with a slightly older version of mythffplay (my master builds do not create mythffplay):

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klaas@myth3:~$ mythffplay
ffplay version 4.2.1 Copyright (c) 2003-2019 the FFmpeg developers
  built with gcc 7 (Ubuntu 7.4.0-1ubuntu1~18.04.1)
This does play the YLE clip correct. There are however differences with the output of ffplay.
The output of mythffplay shows that the video format is initially not recognized, similar to the output of "mythffmpeg -i"

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[mpegts @ 0x7f713c000b80] After avformat_find_stream_info() pos: 0 bytes read:4214928 seeks:3 frames:629
Input #0, mpegts, from '/mnt/store/videos/C_Test/TS/nikkolade/yle-2002120210327155800.ts':
  Duration: N/A, bitrate: N/A
    Stream #0:0[0x136], 0, 1/90000: Video: h264, 1 reference frame, none, 90k tbn
    Stream #0:1[0x352](swe), 0, 1/90000: Audio: ac3 (AC-3 / 0x332D4341), 0 channels
    Stream #0:2[0x355](dut), 0, 1/90000: Audio: ac3 (AC-3 / 0x332D4341), 0 channels
    Stream #0:3[0x467](fin), 0, 1/90000: Subtitle: dvb_subtitle
    Stream #0:4[0x468](swe), 0, 1/90000: Subtitle: dvb_subtitle
    Stream #0:5[0x47f](swe), 0, 1/90000: Subtitle: dvb_subtitle
    Stream #0:6[0x13ec](fin), 0, 1/90000: Subtitle: dvb_teletext
A bit later the video size is however detected:

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Video frame changed from size:0x0 format:none serial:-1 to size:1920x1080 format:yuv420p serial:1
The output of ffplay shows immediately the correct stream info:

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[mpegts @ 0x7f3e64000b80] After avformat_find_stream_info() pos: 0 bytes read:3723408 seeks:3 frames:539
Input #0, mpegts, from '/mnt/store/videos/C_Test/TS/nikkolade/yle-2002120210327155800.ts':
  Duration: 00:21:49.84, start: 49058.512100, bitrate: 5580 kb/s
  Program 1
    Stream #0:0[0x136], 269, 1/90000: Video: h264 (Main), 1 reference frame ([27][0][0][0] / 0x001B), yuv420p(tv, bt709, top first, left), 1920x1080 (1920x1088) [SAR 1:1 DAR 16:9], 0/1, 25 fps, 50 tbr, 90k tbn, 50 tbc
    Stream #0:1[0x352](swe), 159, 1/90000: Audio: ac3 (AC-3 / 0x332D4341), 48000 Hz, stereo, fltp, 448 kb/s
    Stream #0:2[0x467](fin), 0, 1/90000: Subtitle: dvb_subtitle ([6][0][0][0] / 0x0006)
    Stream #0:3[0x47e](fin), 1, 1/90000: Subtitle: dvb_subtitle ([6][0][0][0] / 0x0006) (hearing impaired)
    Stream #0:4[0x13ec](fin), 110, 1/90000: Subtitle: dvb_teletext ([6][0][0][0] / 0x0006)
    Stream #0:5[0x355](dut), 0, 1/90000: Audio: ac3 (AC-3 / 0x332D4341), 0 channels (visual impaired)
    Stream #0:6[0x468](swe), 0, 1/90000: Subtitle: dvb_subtitle ([6][0][0][0] / 0x0006)
    Stream #0:7[0x47f](swe), 0, 1/90000: Subtitle: dvb_subtitle ([6][0][0][0] / 0x0006) (hearing impaired)
Also, ffplay has the correct stream info after reading 3723408 bytes while mythffplay has not yet the correct info after reading 4214928 bytes.
So it looks like that the detection probe size is not the deciding factor.

PaulH has ascertained that mythtv uses ffmpeg version 4.3.1 from 2020. This should be recent enough as the ffmpeg 3.4.8 from Ubuntu 18 is already correct.

This leaves the suggestion from bim-ubunet:
Or the MythTV demuxer does something else that ffmpeg does not
as the most likely direction to search in. However, the inner workings of ffmpeg are a mystery to me. I intend to create an issue for this with a part of the offending YLE clip that is big enough to show the problem and small enough to be attached to the issue. This will enable further investigations by the video experts.

But back to the problem of nikkolade, who cannot play the YLE recordings.
The good news is that this is not a problem with his Radeon videocard or with other hardware.
A workaround for playing back the recordings can be to do a transcode with ffmpeg to something that does play correct. The disadvantage is, as I understand it, that you can then only start viewing after the recording and the transcoding have finished but that is significantly better than seeing only the top/left corner.

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paulh
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Re: HD Playback problem with YLE-channels only

Post by paulh » Wed Mar 31, 2021 3:40 pm

If it is our TS demuxer one possible workaround is to enable 'Use FFmpeg's original MPEG-TS muxer' (Setup->Video->Playback->General Playback)

Although the setting help text does say 'Things will be broken' so :roll: Still be interesting to see if it does improve anything though.

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