Status of Windows tools ==> Linux Solutions

[charlie@a...]

--- In ExtractStream@y..., "Ken Hancock" <hancockks@y...> wrote:
> --- In ExtractStream@y..., Dale Reed <daler@n...> wrote:
> > Well, there is a common assumption that the audio and video 
streams
> > after being split are exact. When in reality, I don't think they 
are.
> 
> Why is this? Both are recorded in CBR. Assuming for every chunk 
you read in 
> from the TiVo you output both audio and video, you should end up 
with the 
> same amount of each.


The TyStream format has synchronization marks that lock the audio and 
video streams together, so if there were any small errors you'd never 
notice them on TiVO itself, only after you try to throw all the 
timing data away and turn it into a format that contains no timing 
information (MPEG elementary streams) and then try to make it 
synchronize.

This is definitely the cause of shows that *start out* 
desynchronized. TiVo doesn't care whether or not it starts the 
streams at the exact same time, because it doesn't have to care.

There's another cause of de-synchronization mid way through the show 
that I've discovered. Extract stream has a nasty habit of getting 
chunks in the wrong place - I mean really wrong, like a half hour out 
of place. These mis-placed chunks get thrown away at conversion time 
and you pretty much never miss them, except that the chunk didn't 
hold an equal amount of audio and video. Get it?