[pulseaudio-discuss] {PATCH][RFC] AC3 passthrough support

[Colin Guthrie]

'Twas brillig, and pl bossart at 13/07/10 21:21 did gyre and gimble:
> Adding this in /etc/asound.rc (more exactly
> /etc/alsa/pulse-default.conf on my Fedora box) work fine:
> 
> pcm.a52 {
>    @args [CARD]
>    @args.CARD {
>        type string
>    }
>    type rate
>    slave {
>        pcm {
>            type a52
>            bitrate 448
>            channels 6
>            card $CARD
>        }
>        rate 48000 #required somehow, otherwise nothing happens in PulseAudio
>    }
> }
> 
> a52:0 is detected by PulseAudio and the encoded output shows as
> 'Digital Surround 5.1 (IEC958/AC3) in pavucontrol.
> 
> I just finished testing all the changes I posted yesterday. Works
> flawlessly, I can switch from 2ch PCM over SPDIF to 5.1 still over
> SPDIF but re-encoded with a52, and unlike the passthrough case I can
> mix the multichannel content with alerts or system tones.
> The only bug I found is that if I change the individual volume on one
> of the channels, there's a ringing noise introduced, and it does not
> go away unless I kill the stream.
> 
> Will prepare a set of patches, Colin it'd be great if you can merge
> them in git master.

Cool :)

-- 

Colin Guthrie
gmane(at)colin.guthr.ie
http://colin.guthr.ie/

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