Hi,

I'm trying to detect North America RING_TONE using spandsp Using default settings  as mentioned follows

   <tone name="RING_TONE" description="North America ring">
         <element freq1="440" freq2="480" min="1200" max="0"/>
   </tone>

But I'm not getting consistent tone detections. Is there any thing that I need to change to have a proper tone detection.

As per the tone/spectrum analysis using audacity. This tone is having two frequencies 440 and 480 a mentioned in conf, but spandsp is not detecting them.

To have a proper and consistent tone detection how much duration I should use?

Please refer spectrum analysis of tone representing 440Hz & 480Hz frequencies.

As per the doc min and max values represents duration. How to determine these durations of any give tone?

What is the meaning of having max  value 0 ?