[mythtv-users] Long delays with remote occasionally

[Yeechang Lee]

Josh Mastronarde <jmastron at gmail.com> says:
> I think that's exactly the problem: Current ffmpeg (and my patched
> probe code from it) sees these as "mpeg2video" when they might not be.
>  I patched in).  If I'm right, you'll have the same issue with 0.22
> (or trunk today).  Either the files have a wrong tag somewhere, or the
> ffmpeg code is broken (or I'm crazy).

After further experimenting, your patch has revealed (or caused) two
different, but related, issues with my older recordings:

* MPEG2 recordings converted using mythtranscode into MPEG4. These
  hang mythfrontend.
* MPEG2 recordings losslessly transcoded using mythtranscode. These do
  not hang mythfrontend; rather, it complains of "NVP: Couldn't find a
  matching decoder for:
  myth://192.168.1.106:6543/1173_20060402232900.mpg".

The good news is that again running lossless transcode (MPEG2->MPEG2
or MPEG4->MPEG4) appears to fix both issues. The danger here is that
the transcode will drop the audio track as discussed at
<URL:http://svn.mythtv.org/trac/ticket/1841>.

> Can you try transcoding one of the recent files using the same
> method on your current install, and see what *that* result looks
> like to ffmpeg?

_Miss Potter_, which plays fine:

FFmpeg version 0.5-30.el5, Copyright (c) 2000-2009 Fabrice Bellard, et
al.
  configuration: --prefix=/usr --libdir=/usr/lib64
  --shlibdir=/usr/lib64 --mandir=/usr/share/man --enable-shared
  --enable-gpl --enable-postproc --enable-swscale --enable-avfilter
  --enable-avfilter-lavf --enable-pthreads --enable-x11grab
  --enable-vdpau --disable-avisynth --disable-libamr-nb
  --disable-libamr-wb --enable-libdc1394 --enable-libfaac
  --enable-libfaad --enable-libfaadbin --enable-libmp3lame
  --enable-libtheora --enable-libvorbis --enable-libx264
  --enable-libxvid --extra-cflags=-O2 -g -pipe -Wall
  -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector
  --param=ssp-buffer-size=4 -m64 -mtune=generic -fPIC
  --disable-stripping --extra-cflags=-I/usr/include/nvidia-graphics
  --extra-ldflags=-L/usr/lib64/nvidia-graphics
  libavutil     49.15. 0 / 49.15. 0
  libavcodec    52.20. 0 / 52.20. 0
  libavformat   52.31. 0 / 52.31. 0
  libavdevice   52. 1. 0 / 52. 1. 0
  libavfilter    0. 4. 0 /  0. 4. 0
  libswscale     0. 7. 1 /  0. 7. 1
  libpostproc   51. 2. 0 / 51. 2. 0
  built on Mar 15 2009 14:08:04, gcc: 4.1.2 20080704 (Red Hat
  4.1.2-44)

Seems stream 0 codec frame rate differs from container frame rate:
1000.00 (1000/1) -> 29.97 (30000/1001)
Input #0, nuv, from
'/misc/silverbox/mythtv/store/1179_20090616102900.nuv':
  Duration: 59:37:58.30, start: 28998.186000, bitrate: 127 kb/s
    Stream #0.0: Video: mpeg4, yuv420p, 1920x1088, PAR 136:135 DAR
    16:9, 29.97 tbr, 1k tbn, 1k tbc
    Stream #0.1: Audio: mp3, 48000 Hz, stereo, s16, 128 kb/s

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