[vdr] Re: Re : VDR files to vob

[Gerald Raaf <graaf@attglobal.net>]

Hi,

i dont think Klaus Schmiedinger should change the the file-format. Wouldn't it
much better if a second cutting mechanism would be integrated, which can selected
in setup -> cutting Normal and cutting to PS. If it where done like this not so
much code have to be changed. And when I understand all in the thread vdr can play
those ps files.
Because I think mostly all users will cut their movies.

kind regards
Gerald

Malcolm Caldwell schrieb:

> I could well be wrong here - it has been a while since I looked at mpeg
> parsers but...  in my recollection:
>
> What people are saying here is correct: a PS is basically PES with some
> additional headers.
>
> One of the things that can be in these headers is the mpeg start code.
> This is a sequence of bytes (0x000001BA unless I am mistaken) that says
> basically "The program stream starts here".
>
> Many mpeg players (all the ones whose code I have read) do something
> like this at the very beginning:
>
> while (nextbytes != MPEG_START_CODE) {
>         skipbytes;
> }
> And then start parsing stream.
>
> In fact, the players I have looked at, after they find the start code
> skip all the other header information and only process the PES packets.
>
> I would guess that not having the start code is what causes many players
> to have troubles.  (Unless vdr already puts in start codes - I have only
> had a quick look at the code)
>
> It should be fairly easy to add the PS headers stuff to the VDR files
> and it would probably help things a lot.
>
> On Mon, 2002-07-15 at 06:14, Andreas Schultz wrote:
> > Hi,
> >
> > On Sunday 14 July 2002 21:12, Klaus Schmidinger wrote:
> >
> > [...]
> >
> > > I guess what I'd first like to see is somebody who can explain
> > > *EXACTLY* what PES and PS is, and what the difference between these
> >
> > I guess i have outed myself already earlier, but let's see if i have learned
> > something.
> >
> > Everything is really explained in ISO/IEC-13818-1.
> >
> > Section 2.4.3.6 describes PES packets. VDR already deals with those.
> >
> > Section 2.5.3.3 describes PS packets. PS streams can contain a number of
> > different packet types. One of those being PES packets, others are mostly
> > only relevant in DVB streams.
> > For us the only relevant PES packet type is 0xBA. It contains a SCR (system
> > clock reference), the stream mux rate and the PES packet itself.
> >
> > So PS streams really are PES stream with an small additional header that
> > contains no really usefull information. The only possible info in there is
> > the SCR, which can be used to sync the decoder to the encoder. But the DVB
> > card is not using this.
> >
> > Andreas
> > --
> > Andreas Schultz <aschultz@cs.uni-magdeburg.de>
> > Student of computer science
> >
> > "In accordance with plans for Linux OS world domination
> >       infiltration of governments is vital (:-))."
> --
> Malcolm Caldwell <malcolm.caldwell@ntu.edu.au>
> Northern Territory University