[Asterisk-Dev] Bounty! For help with echo cancellation code.

echo-asterisk_dev at secondphone.com echo-asterisk_dev at secondphone.com
Tue Jul 13 19:30:10 MST 2004

 From the CLI and during a call I want to be able to:

  *** Pulse the outgoing line and record at least 50 ms of the incoming line.

      The pulse waveform must be specifiable as a series of amplitudes
      for each 1/8000 sec time slot.  It would be best of these values
      could be read from a file specified on the CLI command line.

      Timing should be synced between the pulse and the echo so that the
      delay from the pulse to the echo can be accurately determined.

      Echo cancellation should be disabled during this operation.

      This would operate similar to the echo-training code that operates
      at the initiation of a call except that this could be done at
      any time.

      The initial pulse and any echoes can be combined and saved in a
      single channel.

      Output should go to a file and should be in a simple format that
      a program such as Audacity can read, display and play. 

  *** Pulse the outgoing line and record at least 50 ms of the incoming line.

      Same as above EXCEPT echo cancellation would not be disabled during
      this test and the results of the echo cancellation operations should
      be recorded and saved in a separate channel.

  *** Change variables used to control echo cancellation.

      Only the code in mec2.h is of interest.
      I will help identify the variables and modify the mec2.h code as
      needed to accomplish this goal.

      There are a lot of parameters in mec2.h that may affect the quality
      of the echo cancellation.  I want to be able to adjust them 'on the
      fly' and be able to immediately hear the results.

I am open to alternative proposals which would accomplish the same goals.

Name your price.

echo at secondphone.com

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