Hi all,

Just to come back on an already discussed issue. I'm the proud owner of as well
a PVR-500 as well as a PVR-150. Both cards are working excelent with the
current 0.4.0 ivtv driver. But as I'm living in Switzerland, there are some
cable channels with Dual-Language transmission. As stated in earlier threads,
the detection of SAP/Dual-channel is working perfectly. The only thing that is
not directly working is the dual-channel output of the audio by using "ivtvctrl
-z 1", as I suppose is only working with the PVR-250/350 which contain a MSP34xx
chip for audio detection. A solution to this problem is also already stated in
an earlier thread, namely using "echo PREF_MODE=7 | cx25840ctl -s -d
/dev/video1".
This gives also the possibility in mythtv to select the different audio tracks
by using the seperate left/right channel muting.

The only problem which resides in this solution is:
1) Would it not be a nice idea to update the PREF_MODE to the correct value by
the usage of "ivtvctrl -z 1" for the PVR-150/500 cards?
2) By recording the MPEG stream, although the audio is marked as DUAL, it still
is a single audio stream, and until now I did not find any player/editor who
could handle this type of stream (hence detects that there are actual two
languages instead of a stereo audio stream).

As I do not care about the first point that much, the second point could be a
bit more iffier.
Please correct me if I'm wrong, but by my understanding the MPEG stream is
created by the CX25840 chip by usage of the firmware (hence not by the driver
itself). In case the firmware permits to create two audio tracks in the MPEG
stream (which should be known to the people who have insight in the FW), one
could think of a scheme to instruct the FW to create a MPEG stream containing
one video channel, and two separate audio channels, each containing one
language. This would ease things up for players/editors (as they already
support multiple audio channel streams, as found on DVD's), and also would
provide a nice interface to f.e. mythtv to detect the languages.

I would be interested in helping testing this feature, as you guys think it's
feasable and interesting. I also would apreaceate feedback.

Regards,
T.

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