Digital audio processing

摘要

The invention concerns digital audio processing and in particular the detection of periods where samples can be deleted or repeated unobtrusively so as to change the average sample-rate or to provide time delay modification. Differences between succeeding sample values are evaluated and compared with a threshold and samples are deleted or repeated where two or more consecutive sample value differences are less than the said threshold value.

主权项

1. A method of changing the number of samples representing a time segment of an audio signal by deleting or repeating existing samples at positions in the time segment dependent on the values of said audio samples, comprising the steps of:
receiving an audio signal having a first number of samples representing a time segment, each sample having a sample value; forming differences between the respective sample values of succeeding samples by subtraction; comparing said differences with a threshold value; deleting or repeating samples where two or more consecutive differences are less than the threshold value; and outputting the audio signal with a second, different number of samples representing the time segment; wherein the threshold value is reduced when samples are deleted or repeated and wherein the threshold value is increased when a difference between succeeding samples exceeds the said threshold value.