[mythtv-users] Lossless Transcode 0.25

[Scott & Nicole Harris]

>>> As far as the other suggestion, it's a bit above my paygrade, so I'll
>>> have to look into how to dothat.  Do you mean multiplex one of the "bad"
>>> recordings?

>>It's not at all difficult.  All three of those have some form of GUI
>>available.  Just add one of the bad files into the source list in the
>>GUI, and hit run.  All it's going to do is take those raw codec streams
>>and stuff them into a different container type.  Think of it like
>>extracting files from a ZIP archive and putting them in a tarball.  Your
>>recordings start as an MPEG TS container, and the lossless transcoder
>>outputs an MPEG PS container.  I'm curious as to whether the new bits of
>>video are actually damaged, or if something strange is going on with the
>>container that is giving MythTV troubles.

>OK, here's what we got.  I tried playing a post transcode damaged file with
>VLC (on Ubuntu and Windows).  Where in Myth playback, there would be a 1
>second flash of purple lines, in VLC, it just stuttered all over itself at
>those points.  More accurately, in Myth playback playcback is [fade to
>commercial] -> [purple bars where lossless transcode took the commercial
>out] -> [show picks up at cut point].  In VLC, it was [fade to
>commerical] -> [5 - 6 seconds of black screen] -> [3 or 4 seconds of
>stuttering audio and video before finally "catching" itself about 10 
>seconds
>into the next scene of the show].

>I then used mkvtoolnix and multiplexed it as requested.  When I played that
>file back in VLC, it displayed the purple lines like Myth playback does.

>mkvtoolnix als had some warnings while doing its thing....
> --SNIP --

>Now, one other thing I've noticed.  The purple lines every 50 seconds is 
>not
>as consistent as the purple lines at every removed cutpoint (which is 100%
>of the time) across recordings.   Some files have no 50 second purple and
>some have it every 50 seconds, and it SEEMS (I can't 100% confirm this yet)
>that 720p recordings have it every 50 seconds and 1080i recordings do not;
>again both have them 100% of the time at removed cut points.

The more I go through my 0.25 trancoded files past couple days, it's 
becoming pretty clear that it's the 720p programs (all of them) that are the 
only ones affected with the purple line every 50 seconds....and it really is 
50 seconds, almost to the tick.  The 1080i's only have it at cut points.