[mpeg2] Re: Only _one_ TS recording possible

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

Juergen Weiss wrote:
> 
> Hi,
> 
> There seems to be a problem with the calculation of
> the Bitrate for Transport Stream.
> 
> Setting the TransportRate to
> 
>     P->TransportRate = vidrate+RateArray[kfir->Params.AudioBitRate] * 1000;
> 
> does not seem to be correct and leads to incorrect ts pcr
> fields.  The windows driver does not have a fixed relation
> between BitRate and TransportRate.  With the following change,
> the problem went away. Not sure, if this change solves your
> problem.
> 
>         /*
>          * Rate of Transport Stream
>          * if choosen too low, ts pcr fields are wrong
>          * is there any formula for minimal transport stream rate?
>          * a factor of 1.15 seems to work for
>          * bitrates at least between 0.8 to 4.5 MBit/s
>          */
>         P->TransportRate = ((P->BitRate+RateArray[P->AudioBitRate] * 1000) * 115) / 100 + 80000;
> 
> Juergen Weiss

Hi Juergen,

I tried that, but it didn't change anything.
If there were a basic problem with the pcr fields, I would expect that
to be present in the very first recording, too, since InitParams() is
only called once when the driver is loaded.

The problem I'm observing occurs only with the second (and every following)
recording after the driver has been newly loaded. So I guess it must be
something "left over" from the first recording that disturbs the second one.

I've uploaded a screen shot of such a recording to

  ftp://ftp.cadsoft.de/pub/etc/x2.jpg

interestingly it's mostly the bottom part of the picture that gets distorted.
Maybe somebody can figure out something from looking at this image...

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
_______________________________________________________________