AMD And Fax Detection

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Is it feasible to enhance AMD to detect and report if the far end sends fax tones?

I am guessing that, as it is using DSP to detect sounds and periods of silence, the same DSP can also report if a CED tone is sent.

If it is feasible, is there a document describing the DSP interface that someone who is not familiar with DSP can use to get started?

Neil Youngman

Neil Youngman Developer Wirefast Limited

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2 thoughts on - AMD And Fax Detection

  • I think that there is a much easier way to detect if the far end is a fax. In your dialplan, include a section that uses the ‘fax’ extension. If the call jumps to that extension, then the far end is a fax machine. Regards;
    John V.

    —–Original Message—

  • A quick test to a fax number doesn’t seem to jump to the ‘fax’ extension. I checked faxdetect=both on chan_dahdi.conf. I seem to remember trying this some years back and finding that fax detect only worked for CNG tones, not CED tones?

    Neil Youngman