Hi Freeswitchers:

I have been trying to detect India ringback tone using spandsp.conf.xml

My understanding is that f1 and f2 are the Frequency and min and max is the Tone duration value. For example:

Based on ITU-T reference India progress tones are:

ring = 400*25/400,0/200,400*25/400,0/2000
Questions

a) How to show the Tone frequency received? 
b) What is the meaning for the values assigned to f1 and f2 in debug mode. I see possible values:

c) Is there an option to configure modulation for Tone frequency as specified in ITU standard (*25 above)?
d) Sample configuration will be appreciated.

Configuration

      <tone name="RING_TONE">

         <element freq1="400" freq2="0" min="384" max="400"/>

         <element freq1="0" freq2="0" min="200" max="224"/>

         <element freq1="400" freq2="0" min="384" max="400"/>

         <element freq1="0" freq2="0" min="1968" max="1984"/>

        </tone>

When debugging:

I have enabled already debug level to 2.

2017-02-13 02:59:32.080389 [DEBUG] mod_spandsp_dsp.c:705 Tone segment: f1 = 1, f2 = 2, duration = 400
2017-02-13 02:59:32.300524 [DEBUG] mod_spandsp_dsp.c:705 Tone segment: f1 = -1, f2 = -1, duration = 224
2017-02-13 02:59:32.680369 [DEBUG] mod_spandsp_dsp.c:705 Tone segment: f1 = 1, f2 = 2, duration = 384
2017-02-13 02:59:34.680384 [DEBUG] mod_spandsp_dsp.c:705 Tone segment: f1 = -1, f2 = -1, duration = 1984


http://pastebin.com/xm8xN9R3

Thanks

-Gonzalo