[mythtv-users] Transcoders and closed captions

[jedi]

On Mon, Oct 06, 2008 at 02:44:50PM -0700, Jim Stichnoth wrote:
> It turns out that closed captions are a key part of the WAF.  Normally,
> MythTV's cc support seems great, but there are some problems with
> transcoding.  When I do a lossless mpeg-2 transcode (for permanently
> removing commercials), the captions are lost completely.  When I transcode
> from mpeg-2 to mpeg-4 with a cutlist, the captions are preserved but delayed

     I do mpeg4 transcoding with no fancy stuff. I have never had problems
with losing closed captions in recordings that have them. However, you can
sometimes end up with (correctable) sync issues.

> during playback, presumably because the cutlist is not being applied to the
> captions.  The one workflow I've found that does the right thing is to
> transcode from mpeg-2 to mpeg-4 without a cutlist, then create the cutlist,
> and finally do a lossless mpeg-4 transcode with the cutlist.
> 
> I'm running MythDora 5 (0.21).  Is this a well-known issue?  Would there
> happen to be some patches I can pick up to fix this, or do I need to dig
> into the code myself?
> 
> On a related topic (and please stop me if this is a verboten topic), I've
> noticed that the handful of bittorrent TV programs I've downloaded always
> seem to lack captions.  Is this because of problems with the mpeg-4/cc
> specification, or with support in the encoding tools, or a deliberate
> decision by the people doing the encoding?

     This is just one of those things that most people aren't into. For
some speciality foreign language content (IOW, anime), some people have
interest in captions or subtitles, but for the most part it seems like
people don't care and don't bother. Thus CC & subtitle tools for all 
patforms seem "underdeveloped".

     The current state of the tools hampers my ability to compress content
while still preserving that WAF. Anything of interest to the wife needs to
have intact captions or subtitles.

     BTW, the Hauppauge 1212 doesn't have any CC support.