splitstream

[Joe Boxer]

> On the second try, gcc
> had a problem with
> 'setmode(fileno(stdin), _O_BINARY);' line in int
> main():

That's the one line of code that's windows specific.
You should be able to remove the io.h and the setmode
line and compile and run under linux. The only thing
that might not work is stdin pipes.

> I tested with Basic, Medium, and High quality
> streams. Splitstream
> worked flawlessly in extracting the audio and video
> streams. 
That's really encouraging.


> However,
> when I multiplexed them back together (using
> mjpegtools' mplex), the
> audio and video were still out of sync by as much as
> two seconds.

ok, this is where things get interesting. here is my
experience with these streams:

- If I multiplex and create an mpg file, most players
will not sync the audio properly, except for PowerDVD.
PowerDVD gets it right all the time. To me, this means
there is something wrong with the other software. In
fact, it's obvious from another experiment I did: I
fast forward/reverse a few times and with anything
except PowerDVD, the audio sync changes everytime.

- There is a constant offset (it's been -250 ms for
all my streams). This is easily fixed when creating
avi's.

- When I play the divx 4.0 file, there is no audio
sync problems. the audio is encoded using lame vbr and
added to the avi using nandub.

> The real issue is
> the sync, which I'm sorry to say, still doesn't work
> correctly in
> splitstream. At least on my Tivo.

The main difference between splitstream and
convertstream is the proper processing of the input.
convertstream has several bugs that make it eat the
audio or add junk (anytime you get "audio failure").
The same bugs also create corrupted video. Clearly,
without all the audio and a corrupt video, you will
have severe sync problems. All you really need is
either a player than can play mpeg2 streams properly
(PowerDVD seems to work well) or a conversion process
to whatever format you like that allows you to set the
initial offset (nandub does an excellent job with vbr
mp3's and avi's).

I would be curious if you could create a svcd (with a
proper audio offset) and play it on a consumer dvd
player now that the streams are not corrupt.

Thanks for report. 

Joe


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