[mythtv-users] Suggested bitrate for transcoding HD Mpeg 2 to Mpeg 4

[Neil Salstrom]

On Fri, Jun 3, 2011 at 10:47 PM, Neil Salstrom <salstrom at gmail.com> wrote:
>
> I think you are correct.  I may compile both ffmpeg and x264 myself.
> I had some issues with the transcoding I did.
>
> First, the transcode failed on a file that had two audio tracks.
> Second, in the file that finished encoding had really distorted audio.
>  I'm wondering if a more recent ffmpeg / x264 has fixes for those
> issues.
>

An update to this.

Over the weekend I compiled ffmpeg and x264.  The issue with distorted
audio is gone but I'm still having issues with files with multiple
audio tracks.  Here is what happens when I try to use this script.  It
will make a zero byte file and insert that in to the database fine (so
that portion of the script works) but ffmpeg chokes:

mythtv at htpc:~$ ./x264_transcode_normal.pl -f 1102_20100626140000.mpg
/multimedia/metadata/Banners/1102_20100626140000.mpg does not exist
/multimedia/metadata/Coverart/1102_20100626140000.mpg does not exist
sh: /usr/share/mythtv/metadata/Television/ttvdb.py: not found
/video/Primal_Grill_With_Steven_Raichlen_06.26.2010.mp4 seems unique
ffmpeg version git-N-30535-g124a9ed, Copyright (c) 2000-2011 the
FFmpeg developers
  built on Jun  4 2011 15:38:43 with gcc 4.4.5
  configuration: --enable-gpl --enable-version3 --enable-nonfree
--enable-postproc --enable-libfaac --enable-libmp3lame
--enable-libopencore-amrnb --enable-libopencore-amrwb
--enable-libtheora --enable-libvorbis --enable-libx264
--enable-libxvid --enable-x11grab
  libavutil    51.  4. 0 / 51.  4. 0
  libavcodec   53.  6. 1 / 53.  6. 1
  libavformat  53.  2. 0 / 53.  2. 0
  libavdevice  53.  1. 0 / 53.  1. 0
  libavfilter   2. 12. 0 /  2. 12. 0
  libswscale    0. 14. 1 /  0. 14. 1
  libpostproc  51.  2. 0 / 51.  2. 0
[mpegts @ 0x1a463e0] max_analyze_duration 5000000 reached at 5005000
Input #0, mpegts, from '1102_20100626140000.mpg':
  Duration: 00:29:56.93, start: 75005.058000, bitrate: 3399 kb/s
  Program 1
    Stream #0.0[0x41]: Video: mpeg2video (Main), yuv420p, 704x480 [PAR
10:11 DAR 4:3], 15000 kb/s, 29.97 fps, 29.97 tbr, 90k tbn, 59.94 tbc
    Stream #0.1[0x44](eng): Audio: ac3, 48000 Hz, stereo, s16, 192 kb/s
    Stream #0.2[0x45](eng): Audio: ac3, 48000 Hz, mono, s16, 128 kb/s
(visual impaired)
    Stream #0.3[0x46](spa): Audio: ac3, 48000 Hz, mono, s16, 128 kb/s
Output #0, mp4, to 'Primal_Grill_With_Steven_Raichlen_06.26.2010.mp4':
    Stream #0.0: Video: libx264, yuv420p, 1280x720, q=10-51, 3300
kb/s, 90k tbn, 29.97 tbc
    Stream #0.1: Audio: libfaac, 48000 Hz, 6 channels, s16, 160 kb/s
Codec type mismatch for mapping #0.0 -> #0.1
Old file size = 763665212
New file size = 0
# INSERT INTO recorded
(profile,findid,programid,progstart,hostname,previouslyshown,duplicate,starttime,playgroup,editing,preserve,category,transcoded,stars,watched,description,progend,filesize,title,seriesid,recgroup,bookmarkupdate,timestretch,lastmodified,commflagged,storagegroup,autoexpire,endtime,originalairdate,deletepending,transcoder,chanid,basename,subtitle,recpriority,recordid,bookmark)
VALUES ("Default","0","EP010441480032","2010\-06\-26\
14\:00\:00","htpc","1","1","2010\-06\-26\
14\:00\:01","Default","0","0","Cooking","0","0","0","Margherita\ and\
bacon\ potato\ wood\ oven\ pizzas\;\ sweet\-and\-sour\ duck\;\
bone\-in\ pork\ chops\;\ grilled\ cipollini\ onions\ on\
skewers\.","2010\-06\-26\ 14\:30\:00","0","Primal\ Grill\ With\
Steven\ Raichlen","EP01044148","Default","0000\-00\-00\
00\:00\:00","1","2010\-06\-26\
14\:30\:05","1","Default","1","2010\-06\-26\
14\:30\:00","2010\-06\-05","0","0","1102","Primal_Grill_With_Steven_Raichlen_06\.26\.2010\.mp4","Italian\
Fire","0","170","0");
mythtv at htpc:~$