On Tue, 20 Oct 2020, Amanda Ava Koci Pereira wrote:
Hi guys...
We need some clues about to downmix 5.1 and 7.1 channels to 2 channels
for the moment we are using the following code ->
It works but fails miserably if all channels have data at same time
Is the problem that you get clipping if there is audio on more than one input channel?
In general, if you sum a number (N)( of digital channels which have a maximum amplitude of M, then the maximum amplitude of the sum will be N * M. So in this case you need to reduce the output amplitude by 1/N if you want to keep the maximum amplitude of the sum at M.
So in your case you need to set
#define AR_K_P_ATTENUATION_LEVEL 1.0
according to the number of channels being downmixed per output channel.
/Ricard