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

[Robert Houghton]

On Thu, Jun 2, 2011 at 9:58 PM, Neil Salstrom <salstrom at gmail.com> wrote:

> On Thu, Jun 2, 2011 at 6:17 PM, Neil Salstrom <salstrom at gmail.com> wrote:
> (snip)
>
> >    Stream #0.0[0x31]: Video: mpeg2video, yuv420p, 1280x720 [PAR 1:1
> > DAR 16:9], 38800 kb/s, 59.96 fps, 59.94 tbr, 90k tbn, 119.88 tbc
> >    Stream #0.1[0x34](eng): Audio: ac3, 48000 Hz, 5.1, s16, 448 kb/s
> > File for preset 'hq' not found
> > Transcode failed
> >
> > mythtv at htpc:~$
> >
> > Any ideas?  I did this by file name because I was not sure what the
> > job number was.  Can you give any insight as to what may be going on?
> >
> > Thanks!!!
> >
>
> Ok, talking to myself here... Just in case anyone else had this same
> issue.  I'm using Debian Stable (Squeeze).  The ffmpeg in Debian
> Multimedia does not have a 'hq' preset.  In the script I changed the
> 'hq' callout to 'slow' and it's working.  Here is my list of potential
> presets:
>
> htpc:/home/mythtv# find /usr -iname '*.ffpreset'
> /usr/share/ffmpeg/libx264-medium.ffpreset
> /usr/share/ffmpeg/libx264-lossless_slower.ffpreset
> /usr/share/ffmpeg/libx264-ipod640.ffpreset
> /usr/share/ffmpeg/libx264-fast_firstpass.ffpreset
> /usr/share/ffmpeg/libx264-faster.ffpreset
> /usr/share/ffmpeg/libx264-veryfast.ffpreset
> /usr/share/ffmpeg/libx264-medium_firstpass.ffpreset
> /usr/share/ffmpeg/libx264-slower_firstpass.ffpreset
> /usr/share/ffmpeg/libx264-superfast_firstpass.ffpreset
> /usr/share/ffmpeg/libx264-veryslow.ffpreset
> /usr/share/ffmpeg/libx264-fast.ffpreset
> /usr/share/ffmpeg/libx264-lossless_fast.ffpreset
> /usr/share/ffmpeg/libx264-ipod320.ffpreset
> /usr/share/ffmpeg/libx264-placebo_firstpass.ffpreset
> /usr/share/ffmpeg/libx264-baseline.ffpreset
> /usr/share/ffmpeg/libx264-superfast.ffpreset
> /usr/share/ffmpeg/libx264-slow.ffpreset
> /usr/share/ffmpeg/libx264-veryslow_firstpass.ffpreset
> /usr/share/ffmpeg/libx264-veryfast_firstpass.ffpreset
> /usr/share/ffmpeg/libx264-lossless_slow.ffpreset
> /usr/share/ffmpeg/libx264-slow_firstpass.ffpreset
> /usr/share/ffmpeg/libx264-main.ffpreset
> /usr/share/ffmpeg/libx264-lossless_max.ffpreset
> /usr/share/ffmpeg/libx264-slower.ffpreset
> /usr/share/ffmpeg/libx264-placebo.ffpreset
> /usr/share/ffmpeg/libx264-lossless_medium.ffpreset
> /usr/share/ffmpeg/libx264-ultrafast.ffpreset
> /usr/share/ffmpeg/libx264-lossless_ultrafast.ffpreset
> /usr/share/ffmpeg/libx264-faster_firstpass.ffpreset
> /usr/share/ffmpeg/libx264-ultrafast_firstpass.ffpreset
>
> At this point I'm not sure the differnce between them but I picked
> slow just to test.  I've not watched the resulting file but it seems
> to be working now.
>
> Neil
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>

I think the different distros ship with different presets. Fedora used to
ship an HQ preset, so it still exists on my box. "Slow" and "main" also run
fine for me. The differences only really matter if you are trying to tune
the file to a specific decoder (like ps3 or android) that may not support
some x264 flags.

I build my own ffmpeg with libx264 and libfaac from git. There are tutorials
all over the net on how to re-package from git to .deb or .rpm for your
distro of choice.
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