I am fine tuning the echo canceller configuration in linphone for a custom hardware board. I am trying to use the test_ecc tool to estimate the hardware delay, but have found that the measured delay depends on the ec_tail_len value. If ec_tail_len is increased, the measured ec_delay decreases, and vice-versa:
Indeed, the documentation (http://www.linphone.org/technical-corner/linphone/documentation
) states the following:
#Use this when you have a fixed latency in the sound hardware.
#This allows to reduce the tail length of the echo canceller, which speeds up convergence
#and reduces complexity of computations.
#Tail length of echo canceller in milliseconds.
#Ideally it should be no more than the expected duration of the echo.
So: What is the recommended process to come with optimal values for these two parameters?