[vdr] bitstreamout-0.70 and vdr-1.3.21

Dr. Werner Fink werner at suse.de
Fri Mar 11 12:26:19 CET 2005

On Fri, Mar 11, 2005 at 10:59:46AM +0200, Per Mellander wrote:
> Tested all night and as said earlier, by using 'loop mode' the A/V sync 
> problem is solved.
> My problem still apply - DD/AC3 does not work! Reciever detects both DD2.0 
> and DD5.1 but as before there is no sound.
> I double checked by disconnecting SPDIF cable from DVB card to CMI8738 card 
> to make sure the loop mode was 'active'. There must be something 'fishy' in 
> my setup, or maybe my reciever will never work with this setup. ( Which is 
> strange because it works very well with my standalone DVD player. )
> @Werner:
> Any diagnostic test ideas?

Then your sound card does not support the nonaudio bit
or you've set the Z680 option to yes, that means skip
setting of the nonaudio bit.  You may try to set
the Z680 option to `no'.

> I might have missed if there is any tool in your plugin to natively send 
> DD/AC3 from the CMI8738. I will search for an easy way to test what happens 
> if I send DD/AC3 from CMI8738 to reciever. ( ie not a DVB/VDR stream. )

Natively send DD/AC3 would cause a very noisy environment.
There are two method to transport DD/AC3 over S/P-DIF
aka IEC (60)958 ... one is a 32bit method and the other
is the 16bit embbeding method into a PCM stream accordingly
to IEC 61937.

For the first solution you've to generate the S/P-DIF
stream its self. In other words you need access and
docs of the HW of a programmable sound card (chip).

The second solution is more flexible: it should be
usable with any sound card, and if this sound card
is able to support nonlinear S/P-DIF streams which
are used to transport the nonlinear PCM data most
receivers out there should work.

-> http://www.epanorama.net/documents/audio/spdif.html


AC3 loop through sound card http://bitstreamout.sourceforge.net/
Howto http://www.vdr-portal.de/board/thread.php?threadid=1958
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