[vdr] Re: what causes cTS2PES errors?

[Klaus Schmidinger <Klaus.Schmidinger@cadsoft.de>]

Rene Bartsch wrote:
> 
> Am Mon, 2003-05-26 um 17.26 schrieb Klaus Schmidinger:
> > Rene Bartsch wrote:
> > >
> > > Am Son, 2003-05-25 um 18.55 schrieb Gregor Lawatscheck:
> > >
> > > >
> > > > It might have to do with the fact the budget cards give a "raw" TS stream
> > > > whereas the full featured cards give a filtered one that might already have
> > > > eliminated reception errors?.
> > >
> > > The full-featured cards demux/remux the stream with their ARM using
> > > CRC-code.
> > >
> > > @Klaus Schmidinger: Does VDR check the TS with CRC-code?
> >
> > No.
> >
> 
> That explains a lot of problems with invalid MPEG-streams (and why
> MPlayer swallows with VDR-recordings).
> 
> Because of aerial circumstances (rain, snow, clouds, electricity,
> overlieing waves of other transmitters, ...) you NEVER receive 100% of a
> transmission (even harddisks use CRC for checking the data coming from
> the IDE-interface or read from disk for bit-errors - on a 45 cm
> copper-line or on 5 cm wire in the disk ...).
> 
> CRCs are a basic need for digital, aerial transmissions to keep the
> bitstream valid. All streams will be corrupt without CRC (full-featured
> cards do CRC-checking when filtering).
> 
> So this should be added as fast as possible (before 1.2.0 to have a
> really stable system). This also would increase reception in case of bad
> weather.

Well, I have no such problems with VDR itself, so I'd still say it is stable.
Besides, I always assumed that the TS packets delivered by the driver (be it
full featured or budget cards) were already CRC checked. If they aren't,
wouldn't the _driver_ be the place to do this? Otherwise every single application
would have to implement this...

Klaus
-- 
_______________________________________________________________

Klaus Schmidinger                       Phone: +49-8635-6989-10
CadSoft Computer GmbH                   Fax:   +49-8635-6989-40
Hofmark 2                               Email:   kls@cadsoft.de
D-84568 Pleiskirchen, Germany           URL:     www.cadsoft.de
_______________________________________________________________


-- 
Info:
To unsubscribe send a mail to ecartis@linuxtv.org with "unsubscribe vdr" as subject.