Hi all,

Playing with mod_opus came up with the following.

I am trying to recompile the codec with 8Khz and 40ms ptime. I am not familiar with the codec internals and not really sure what parameters should I change…

In mod_opus.c :

Line 59:

int bitrate_bps = codec->implementation->bits_per_second;

                int use_vbr = 1;

                int complexity = 10;

                int use_inbandfec = 1;

                int use_dtx = 1;

                int bandwidth = OPUS_BANDWIDTH_FULLBAND;

int err;

I suppose that the bandwidth must be changed to OPUS_BANDWIDTH_NARROWBAND and use_vbr=0 and I haven’t found yet whether the FEC parameter is passed to opus encoder.

And in Line 184 , I think the following parameters must be changed

 switch_codec_interface_t *codec_interface;
 int samples = 480;
 int bytes = 960;
 int mss = 10000;
 int x = 0;
 int rate = 48000;
 int bits = 32000;

Can you propose any values about these parameters to achieve 8khz with 40ms packet time?

Thanks for any help,

Dimosthenis