[mythtv-users] Mytharchive errors

Harry Devine lifter89 at comcast.net
Sat Dec 6 02:30:13 UTC 2008

Rod Smith wrote:
> The MythTV transcoders can all be customized, so it's impossible to say for 
> certain what the autodetect transcoder does on any given system without 
> checking its settings. On *MY* system, the autodetect transcoder does a 
> lossless transcode, meaning that it just cuts out anything that's flagged for 
> removal via manual editing and does some minor cleanup. Lossless transcodes 
> run quickly but don't change resolution or bitrate. I don't recall if 
> autodetect doing a lossless transcode is the default or if I changed that.
> When burning to DVD, there's little point in transcoding via MythTV ahead of 
> time, except possibly for a lossless transcode to cut out unwanted material. 
> A non-lossless MythTV transcode will convert to MPEG-4 or RTjpeg, depending 
> on how it's configured, but DVDs must be burned in MPEG-2 format -- and with 
> a limited set of options for resolution and some other parameters, too. Thus, 
> if you plan to burn to DVD, it's best to do one of two things:
> 1) Record directly in MPEG-2 format at 720x480 resolution (for NTSC; IIRC,
>    it's 720x576 for PAL) and burn that to DVD without transcoding it, or
>    at most do a lossless transcode on the material.
> 2) Record in whatever format is an option for your hardware and transcode just
>    once. This transcode can be:
>    a) In MythArchive
>    b) Prior to using MythArchive, using a non-MythTV transcode tool (such
>       as mencoder or ffmpeg directly)
> Note that even if you record in a DVD-ready format, you may need to transcode 
> if your recording is too big for your DVD.
> I hope this makes sense; it's getting late for me, so I might not be writing 
> as clearly as I'd like.

I'm not sure I'm following you 100% as far as what transcoding is 
actually doing.  For example, I'm looking at the Transcoders area in my 
Frontend setup, and they are the default settings from when MythTV was 
installed.  They all seem to have RTjpeg as the Video codec, and MP3 for 
the Audio codec (with a sampling rate of 32000).  This is the same for 
Autodetect, High Quality, et al.

So, if a DVD has to be in mpeg2 format, how do I set up one of the 
transcoders to do this so I can transcode it properly before trying an 
archive operation?  Also, I did see the following error in my 
mytharchive log, and I wonder if this would go away once the transcoding 
problem is straightened out:

WARNING: frames rates do not match
The frame rate for ntsc should be 29.97 but the stream info file report 
a fps of

Thanks!  Sorry about not understanding completely.

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