[vdr] Re: Problems playing DVD

[Andreas Schultz <aschultz@cs.uni-magdeburg.de>]

Christoph Rieder wrote:
> Andreas Schultz wrote:
> 
>> AC3 software decoding probably takes too long. Since decoding happens 
>> in the input thread, the output ringbuffer could underflow causing the 
>> stops.
>> You could try the -nav10 patch with liba52, it might or might not be 
>> faster than the old ac3dec.
> 
> 
> vdr -a "cat > /dev/null"
> 
> should not do any ac3 decoding, right?

no, we always do the decoding, that is needed to get the analog audio 
out working. You could remove the AC3 decoding from 
cDVDplayBuffer::decode_packet().

> I tried that, but with no effect. And I forgot to mention it in my 
> initial post but on the lower end of the image you can see a part out of 
> the center of the image.

maybe a problem with the data transfer to the card? but i assume 
recording and playback work correctly.

> Can the css decoding be the problem? How CPU intensive ist that?
> According to top the CPU ist 0% idle (80% vdr 20% system)

you do have DMA enabled for the DVD drive?

> And why do we have to decode AC3 into PCM? shouldn't DVD's contain PCM 
> audio?

almost all DVD's i have seen do not

> BTW Andreas: I followed your instructions on how to setup libdvdread and 
>  it improved performance. The pauses are shorter now.

glad to hear that!

> Christoph

Andreas