[vdr] Re: AC3-playback didn't work

[Hans-Peter Raschke <Hans-Peter.Raschke@Wintermann-DatenService.de>]

Hello,

for me I solved the problem:

I am using a newer oss (5.64, cmpci) driver from
http://members.home.net/puresoft/cmedia.html (currently I discovered
that there seems to be a newer one (5.68) on the cmedia web site). This
driver supports AC3 via SPDIF like the Soundblaster oss driver.

Afterwards I modified the ac3dec source from the alsa-project to honour
the oss interface. With this combination it is possible to use SPDIF for
AC3.

There are some flaws in this combination:
- SPDIF loop support (needed when you want to route
  the SPDIF signal of the DVB card through your soundcard).
  This option must be set via a module parameter. But 
  if SPDIF loop is activated there is no PCM or AC3 output
  via SPDIF. I added an IOCTL to the sound driver to solve
  this for runtime, but I think it would be better if the
  author would make a change in his code. It could be
  achieved also by loading and unloading the driver in an
  appropriate way.
- If you are using MPlayer and you want to use the soundcard
  then MPlayer is blocked by the running ac3dec (it opens
  /dev/dsp). This could be changed by some modifications of
  VDR.

Hans-Peter Raschke

BTW: MPlayer AC3 ouput works with a modification too!

johannes.schoeller@gmx.at schrieb:
> 
> hallo hans.peter, jens und marcus!
> 
> auch ich habe EXAKT das selbe problem und schon diverse
> kernel, driver, tools und lib kombinationen ohne erfolg
> durchprobiert.
> 
> habt ihr inzwischen schon eine loesung ??
> wenigstens gut zu wissen dass ich nicht alleine bin. ich kenne
> inzwischen noch ein paar andere die genau das selbe problem
> haben.
> 
> inzwischen sind fuer schon fast genug fuer eine eigene mailing
> list, oder zumindest eine selbsthilfegruppe. ;))
> 
> servus hannes!
> 
> > >But with -C or -P the process runs in a neverending loop.
> > >An abort with Ctrl+C doesn't work. Following error message
> > >is displayed:
> > >
> > >htpc:/ # /usr/bin/ac3dec /tmp/ac3file -C
> > >AC3 Stream 48.0 KHz 448 kbps
> > >Aborted...
> > >ALSA lib pcm_hw.c:278:(snd_pcm_hw_drain) SNDRV_PCM_IOCTL_DRAIN failed:
> > >Input/output error
> > >ac3dec: pcm.c:210: snd_pcm_hw_free: Assertion `snd_pcm_state(pcm) ==
> > >SND_PCM_STATE_SETUP || snd_pcm_
> > >state(pcm) == SND_PCM_STATE_PREPARED' failed.
> > >Aborted...
> > >ALSA lib pcm_hw.c:278:(snd_pcm_hw_drain) SNDRV_PCM_IOCTL_DRAIN failed:
> > >Input/output error
> > >ac3dec: pcm.c:210: snd_pcm_hw_free: Assertion `snd_pcm_state(pcm) ==
> > >SND_PCM_STATE_SETUP || snd_pcm_
> > >state(pcm) == SND_PCM_STATE_PREPARED' failed.
> > >Aborted
> >
> > You are not alone.. I have exact the same situation here. I can see on the
> > DD-Receiver
> > that it switches to the optical input (so somehow the output of the card
> > gets activated),
> > but no sound is coming and ac3dec consumes 99% of the CPU must be killed
> > with "killall
> > -9 ac3dec".
> 
> --
> GMX - Die Kommunikationsplattform im Internet.
> http://www.gmx.net

-- 
Hans-Peter Raschke           Tel.:   +49 441 9304064
Wintermann DatenService      Fax:    +49 441 9304069
Langenweg 16                 D-26125 Oldenburg
mailto:Hans-Peter.Raschke@Wintermann-DatenService.de