[mythtvnz] Transcoding help?...

Sat Aug 15 10:24:59 BST 2009

On Wed, 12 Aug 2009 21:43, Ross and Jemima Knudsen wrote:
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> <blockquote cite="mid:200908120738.25019.hoiho.nz at gmail.com" type="cite">
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> Yes I noticed that too.
>
> I have found that if you use mythtranscode the sound sems to stay in sync
>  very nicely ... the downside being that there are fewer knobs to "twiddle"
>  and you get a nuv file that might have to be processed again to get to a
>  more standard container format.  Also as I pointed out it seems to be
>  "flakey" at the moment with approx 5% of my transcodes failing .
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> 5% fail rate isn't too bad (unless the recording is destroyed in the
> process).&nbsp; What parameters do you use for mythtranscode?&nbsp; Is
> there a way to get it to just edit using the cut list without altering the
> content?&nbsp; Changing container formats shouldn't be a major as long as
> the AV stays in sync after.<br>
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1) I dont mind if you prefer to use html formatting for your email but please 
configure your mail client to also send a plain text version of the message 
so that people like me do not have to decipher messages like the above.

2) I cant really help with mythtranscode parameters ...  I seem to recall that 
you were original requirements were to save disk space by archiving some of 
your recordings.

I have now found two new programs - mytharchive and mythreplex which may be 
more suited to your needs.

My objectives are entirely different to yours ... I am looking to get to 
simpler/smaller files that will playback on my Front end - a rather ancient 
IBM thinkpad

3) The issues with mythtranscode as I see them at the moment are:
 - only video codecs available are mpeg4 or rtjpeg
 - only audio codec available is mp3
   As a result any lossless transcoding of h264 streams will end up
   significantly larger file sizes than the original

 - As I reported previously mythtranscode seg faults too often for my liking

   further checking on this issues seems to indicate that the seg faults occur
   shortly after a burst of "transmission error???" messages so this may
   not be an issue for others.  ( I freely admit my antenna arrangement
   is currently sub-optimal - "rabbit ears" even though I have line of
   sight to Mt Kau Kau).

   Interestingly enough ffmpeg correctly processes files that mythtranscode
   chokes on.

4) My main issue with ffmpeg is maintaining A/V sync ... -target pal-dvd seems 
to be the best but still not great. 

5) I am going to explore mythreplex as that seems to have syncing tools built 
in.

Ross I will private message you if I make any real progress.

Regards

Tony Sauri