METHOD AND APPARATUS FOR AUTOMATIC MEASUREMENT OF DELAY TIME FOR ECHO PATH PREDICTION OF ADAPTIVE FILTER IN SET TOP BOX VIDEO AND VOICE CALL SERVICE

摘要

The present invention relates to a method and an apparatus for automatically measuring delay time for predicting a path of echo of an adaptive filter in a set-top box image and a voice call service. The method for automatically measuring delay time includes the steps of: generating a test signal with a single frequency on an input path for a received signal, which is input in a voice input and output device; encoding the received signal including the test signal; change a frequency of the encoded first signal; sensing the test signal in the second signal of which the frequency is changed; and calculating the minimum average of difference between the time of generating the test signal and the time of sensing the test signal. The minimum average is used to generate a filter coefficient of the adaptive filter.