[pulseaudio-discuss] 7.1 surround problem

[Colin Guthrie]

'Twas brillig, and Brendon Costa at 24/06/10 07:38 did gyre and gimble:
> Thanks for the info. It seems the channel mapping init is the problem.
> 
> pa_channel_map_init_auto()
> 
> From the docs it seems like it does not have a default mapping for 7
> or more channels.

>From a quick look at the code: for the case of PA_CHANNEL_MAP_AIFF (aka
PA_CHANNEL_MAP_DEFAULT), there is no support for 8 channels (7.1) (note
that exactly 7 channels is generally not supported anywhere - only
mention it due to your "7 or more) comment :)).

Using PA_CHANNEL_MAP_ALSA has support for 8 channels.

Due to compatibility with RFC3551, I'm not sure if the default channel
map should support 8 channels or not. I've only glanced at the spec but
it only seems to mention up to 6 channels. I'm not sure if there is a
generic extension case to >6 channels or not (I didn't read that deeply).

HTHs

Col

(oh and don't be afraid to look at the PA source. It's good to ask
questions, about bits of it (like 8 channel support with the default
channel map) but it wouldn't have taken you long to know as much as me
about the above!)

-- 

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

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