Patent ID: 7949015
Filing Date: 2011-05-24
Classification: G06F,H04J,H04L

Abstract:
1. A method in a receiving communicating device of compensating for a difference between a clock-frequency controlled sample rate of the receiving communicating device and of a sending communicating device, wherein the sending communicating device transmits packets comprising M audio samples to the receiving communicating device, where M is an integer greater than zero (0), said method comprising the steps of: receiving 0, 1, or 2 packets comprising audio samples; storing the audio samples in a buffer accommodating at least 2·M audio samples in the receiving communicating device before play-out; storing the actual time of reception of each of the received audio samples; continuously updating an estimation of a clock skew (τ) from a calculated accumulated difference between an expected time of reception and the stored actual time of reception of the audio samples; before play-out, calculating an adjusted number N of audio samples to be read from the buffer using the estimation of the clock skew, where N is an integer greater than zero (0) and less than a number of audio samples (b) stored in the buffer; reading N audio samples from the buffer; and resampling by interpolation, the N audio samples read from the buffer to M samples to play-out.