[mythtv-users] Channel scanner won't find a specific channel

[John Pilkington]

On 04/02/16 20:39, David Parker wrote:
> I do know that the signal strength dropped from 92% to 87% when it hit
> QAM-256 channel 115 in the scan, then went back up on the next channel.
> When I actually tune to the channel in Live TV mode, it shows a signal
> strength of 91%.
>
> mythffmpeg reports the following:
>
> # mythffmpeg -i hd_test_1.dat
> ffmpeg version 1.2.7 Copyright (c) 2000-2014 the FFmpeg developers
>    built on Feb  2 2016 10:27:10 with gcc 4.9.2 (Debian 4.9.2-10)
>    configuration: --prefix=/usr/local/mythtv-0.27-2255patch
>    libavutil      52. 18.100 / 52. 18.100
>    libavcodec     54. 92.100 / 54. 92.100
>    libavformat    54. 63.104 / 54. 63.104
>    libavdevice    54.  3.103 / 54.  3.103
>    libavfilter     3. 42.103 /  3. 42.103
>    libswscale      2.  2.100 /  2.  2.100
>    libswresample   0. 17.102 /  0. 17.102
>    libpostproc    52.  2.100 / 52.  2.100
> [mpeg2video @ 0x1372000] 0x0 is invalid
>      Last message repeated 9 times
> [mpegts @ 0x136fa20] Stream #0: not enough frames to estimate rate;
> consider increasing probesize
> [mpegts @ 0x136fa20] PES packet size mismatch
> Input #0, mpegts, from 'hd_test_1.dat':
>    Duration: 00:00:37.09, start: 13266.651322, bitrate: 15013 kb/s
> Codec 0x20000 is not in the full list.
>      Stream #0:0[0x0]: Data: unknown_codec, 18399 kb/s
>      Stream #0:1[0x6f]: Video: mpeg2video (Main), yuv420p, 1280x720 [SAR
> 1:1 DAR 16:9], 59.94 fps, 59.94 tbr, 90k tbn, 119.88 tbc
>      Stream #0:2[0x70]: Audio: ac3, 48000 Hz, 5.1(side), fltp, 384 kb/s
> At least one output file must be specified

Hmm.  Don't know what stream #0:0 might be, but that looks like the 
likely problem.   Do your other myth recordings have something similar? 
Have you tried 'lossless transcode', mythtranscode -m ?
That might remove it.

mythtv 0.28-pre now has mythffmpeg v 2.8.5.   Maybe your mplayer is more 
up-to-date than your mythffmpeg.   But if we're comparing similar 
channels that wouldn't explain the difference you see.

>
> And I got an error when I tried to run a conversion:

It's an mpeg2-ts file anyway.  I'm not sure what you hoped for :-)
>
> # mythffmpeg hd_test_1.dat
> ffmpeg version 1.2.7 Copyright (c) 2000-2014 the FFmpeg developers
>    built on Feb  2 2016 10:27:10 with gcc 4.9.2 (Debian 4.9.2-10)
>    configuration: --prefix=/usr/local/mythtv-0.27-2255patch
>    libavutil      52. 18.100 / 52. 18.100
>    libavcodec     54. 92.100 / 54. 92.100
>    libavformat    54. 63.104 / 54. 63.104
>    libavdevice    54.  3.103 / 54.  3.103
>    libavfilter     3. 42.103 /  3. 42.103
>    libswscale      2.  2.100 /  2.  2.100
>    libswresample   0. 17.102 /  0. 17.102
>    libpostproc    52.  2.100 / 52.  2.100
> [NULL @ 0x2285a20] Unable to find a suitable output format for
> 'hd_test_1.dat'
> hd_test_1.dat: Invalid argument
>
>      - Dave
>