Re: Help on specifying 'chmap' in asound.conf

[Takashi Iwai <tiwai@suse.de>]

On Tue, 16 Jul 2024 08:09:21 +0200,
Xinhui Zhou wrote:
> 
> Dear all,
> 
>    I am having a question regarding how to specify 'champ' for a
> plugin.  I do not see any examples of this. I tried many ways to
> specify but failed.
> 
>   As indicated by the link below,   I can specify the MAP as a string
> array.   Can someone provide one example on how exactly this    [chmap
> MAP]  can be specified?
> 
> "
> pcm.name {
>         type cras
>     [chmap MAP]     # Provide channel maps; MAP is a string array
> }
> "
> https://www.alsa-project.org/alsa-doc/alsa-lib/pcm_plugins.html
> 
> 
> I can something like these, but none of these work for me.
> 
> chmap LFE
> chmap "LFE"
> chmap FR,FL,LFE
> champ "FR,FL,LFE"

You need to define a composite array, e.g. pass like
    chmap [ "FL,FR" ]
instead.

For multiple configurations, you can put more items such as
    chmap [ "FC" "FL,FR" "FL,FR,FC,LFE" ]


HTH,

Takashi