0.4.1&0.4.0 Linux&Windows client MPEG2 PS&TS broken?

Johann Hanne jonny at 1409.org
Wed Jul 10 20:21:08 CEST 2002


> >>Vlc can play MPEG-TS files from disk. It also can read them when there 
> >>is a MP-TS (Multi Program Transport Stream) PAT and PMT's. Then you have 
> >>to choose the right PMT from the menu View|Program. This might work.
> > 
> > When I try to play the stream, the View|Program option is greyed out, i.e. 
> > not selectable.
> > 
> As I said *might work*
Ok, than I've just misunderstood that. I am now streaming the data via UDP 
with one send()-call per 188 byte TS packet just to exclude the file input 
as a possible cause of my problems.

> PAT (pid 0) --> PMT (pid ??) --> Video (pid ??)
>                               --> Audio (pid ??)
>                               --> Audio(n) (pid ??)
>                               --> PCR (pid??)
Ok. This was my level of knowledge for the MPEG (MP)TS. I was confused by 
the SPTS term as i assumed there must be substantial difference between 
MPTS and SPTS. But as the only difference is the number of referenced PMT 
PIDs in the PAT I think the usage of two different terms for the same 
thing is not very logical...

> Look at: http://www.erg.abdn.ac.uk/research.html
> Some other pointers: http://www.mpeg.org/MPEG/index.html and 
> http://www.wotsit.org/search.asp?page=2&s=animated
Thanks for that links. I'll read through them.

> Can you read the stream directly from the DVB-card with vlc. Either 
> through the satellite plugin or with "cat /dev/ost/dvr" | vlc /dev/stdin" ?
I didn't try it out. However I was able to play the recorded TS with WMP 
and the Elecard MPEG2 stuff. It also worked to convert the stream with 
ts2ps and to play the result with MPlayer.

> > I *have* a DVB-C. But as far as I have understood the only (?) problem is, 
> > that the full-featured DVB-cards (not-Nova) cannot pass the complete TS 
> > through, but only up to 8 (?) single PIDs. So if I modify the PAT to only 
> > reference one program, the TS should be "complete" again?
> No, the driver forgets a "start unit indicator". It indicates the start 
> of a new PES packet in the TS header. We notified the author of the DVB 
> driver.
> On top of that there are not PCR's and DTS in the stream. The lack of 
> DTS possibly does not need to be fixed. But the PCR time base needs to 
> be recreated. However this is not an easy task.
So the whole point of our discussion is that the stream coming from my 
card isn't complete/correct. I'll try to make some workaround for it, 
including the PCR recreation although I'm not quite sure if I will 
succeed. If I do, I will post a report on the list. If anyone has some 
hints/links on PCR creation, please let me know.

However, I still wonder why I can play the recorded stream with MPlayer as 
well as with WMP with the MPEG2 stuff added. The POSSIBILITY to modify vlc 
to also support that kind of stream must exist?!

Cheers, Jonny <jonny at 1409.org>



-- 
This is the vlc-devel mailing-list, see http://www.videolan.org/vlc/
To unsubscribe, please read http://www.videolan.org/lists.html
If you are in trouble, please contact <postmaster at videolan.org>



More information about the vlc-devel mailing list