DVD writing

[billyb111b]

I dont think it necessarily the TiVo getting it wrong, but 
Extractstream not nailing the file-sector relationship. I have 
noticed that if you have a "fragmented" tivo, with some Medium, a 
little High, and some Best recordings thrown in. ES will usually 
screw up at the beginning and end of each file part, usually only a 
chunk or two, but since the chunk format does not always have the 
same audio and video together, its enough to throw off synch. 
Sometimes TyConvert can plow through the errors and you'll get tiny 
pieces of other shows (splitstream can show you these). Sometimes 
Tyconvert will completly barf.. who knows how much the streams are 
off.

This is all speculation on my part, but I recently restored a backup 
and there is NO TivoMadd Partitions, No blessed 2nd drive 
partitions, and all recording is at Best, and I have yet to get a 
bad timecode and/or chunk in a stream... this is only a few days of 
research though...

billy



--- In ExtractStream@y..., David Gerdes <dpgerdes@r...> wrote:
> 
> I see the same thing. On two different Tivo units, one running 
1.3 and 
> one 2.01 I get glitches in my streams. Some are very minor, some 
are many 
> seconds of garbage. Any glitch seems enough to screw up the final 
stream 
> when mplexing them back together.
> 
> Most glitches are visible both on the stream and played directly 
on Tivo.
> 
> This is why we need tools to keep the streams in sync when they
> are separated and rebuilt. I think spliting and rejoining 
synced 
> streams should be easy enough. But then re-encoding both the 
> video and audio and trying to keep them this sync data seems like 
a 
> monumental task. 
> 
> I am starting to think of my Tivo as just a VCR for temporary 
recording 
> of shows. I am thinking about looking at some of these PC based 
capture
> cards to be able to start with a known good stream.
> 
> I currently have my Linux drive full of TyStreams that I don't 
know what
> to do with. I am going to start looking to see what is the 
cheapest 
> large scale archival medium out there today so I can hang on to 
the streams 
> until we have tools to keep them in sync. I can always use 
playitsam to 
> replay them back onto the Tivo in the interim. I do like that 
program.
> 
> 
> Michael Patterson wrote:
> > 
> > I'd like to add my personal audio problems to this list :)
> > 
> > I've been working ont he DVD writing thing for some time, and 
I've gotten to
> > a frustrating point.
> > 
> > I split the ty stream into audio and video, and then manually 
add/remove
> > sound from the beginnning of the audio stream until I get it to 
synch with
> > the video.
> > 
> > Great! So I pipe it in through TMPEG to mux the streams (and do 
minor
> > editing), and find that there is a loss of sync part way 
through! (by
> > watching the end). I have not checked to find out where the two 
go out of
> > sync, but I have a suspiciion...
> > 
> > There are two spots where the video glitches slightly. These 
glitches dont'
> > show up on the TIVO, just my streams. I suspect this is causing 
the loss of
> > sync.
> > 
> > When I pull out the ty stream from the TIVO, I get about a 4gig 
file. If I
> > try to use mot tools to split the stream, or convert to MPEG2, I 
end up with
> > only about 250 megs of video data, which doesnt' play.
> > 
> > --Mike
> > 
> 
> 
> -- 
> David