Ryan Courtnage - 2008-01-20

Hi,

I have a .mkv that fuppes is transcoding to mpg.  This works fine.
Fuppes is also transcoding the liba52 audio to stereo mp2.  This is where I'm having a problem.  The resulting audio sounds terrible, seemingly void of all the higher-pitched sounds. Here's the relevant section of fuppes.cfg:

      <file ext="mkv">
        <type>VIDEO_ITEM</type>
        <mime_type>video/x-matroska</mime_type>
        <transcode enabled="true">
          <transcoder>ffmpeg</transcoder>
          <ext>mpg</ext>
          <mime_type>video/mpeg</mime_type>
          <video_codec>mpeg2video</video_codec>
          <video_bitrate>1800000</video_bitrate>
          <audio_codec>mp2</audio_codec>
          <audio_samplerate>44100</audio_samplerate>
          <audio_bitrate>192000</audio_bitrate>
        </transcode>
      </file>

Here's the output on the fuppes console:

  Duration: 01:40:56.6, start: 0.000000, bitrate: N/A
    Stream #0.0(eng): Video: h264, yuv420p, 1280x544 [PAR 1:1 DAR 40:17], 23.98 tb(r)
    Stream #0.1: Audio: liba52, 48000 Hz, 5:1
Output #0, mpeg, to '/tmp/fuppes/1.mpg':
    Stream #0.0: Video: mpeg2video, yuv420p, 1280x544 [PAR 1:1 DAR 40:17], q=2-31, 1800 kb/s, 23.98 tb(c)
    Stream #0.1: Audio: mp2, 44100 Hz, stereo, 192 kb/s
Stream mapping:
  Stream #0.0 -> #0.0
  Stream #0.1 -> #0.1
No accelerated IMDCT transform found

... not sure if I should be concerned about that last line?

As a test, I used ffmpeg to convert the video with the same options that fuppes would be using:

ffmpeg -i movie.mkv -vcodec mpeg2video -b 1800000 -acodec mp2 -ar 44100 -ab 192000 -ac 2 -ab 192000 -r 44100 -f mpegts -y movie.mpg

.. the resulting .mpg can be streamed to my PS3 with great sounding audio.  This makes me think it's related to fuppes' "on the fly" transcoding.  Any ideas?

On a side note, I think I misunderstand what transcoding_release_delay is supposed to do.  In my PS3 device section I can set this to 50, 500, or 0 - all with no obvious effect.  I would expect this to create a delay before fuppes sends the transcoded file to my device (kinda like buffering)?

I'm currently using r586

Thanks!