route and chmap

Jonas Holmberg jonashg at axis.com
Thu Mar 26 14:41:11 CET 2020


Hi,
I use the route plugin to copy mono to both FL and FR (front left and 
front right stereo) of the slave during playback. When get_chmap() is 
called in the route plugin it will call get_chmap() of the slave, 
which returns 2 channels with FL and FR positions, and then route 
itself returns 1 channel with FL position. But the application that 
called snd_pcm_get_chmap() on the playback device expected to get 
position MONO instead of FL since the number of channels is 1.

Is the application wrong in not accepting the chmap or should the 
route plugin have changed position from FL to MONO? Is it possible to 
add something to the config (asound.conf) to make FL become MONO in 
the reply of get_chmap() or solve the problem in any other way?

BR
/Jonas


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