Patent ID: 7024260

Claim:
An apparatus for processing a digital audio signal having a sequence of samples, the apparatus comprising: first means for detecting maximal values and minimal values represented by samples of the digital audio signal; second means for detecting a number of samples from a sample representing a minimal value detected by the first means to a maximal-value-corresponding sample representing a maximal value detected by the first means; third means for detecting a number of samples from a sample representing a maximal value detected by the first means to a minimal-value-corresponding sample representing a minimal value detected by the first means; fourth means for calculating a first difference between the maximal value represented by the maximal-value-corresponding sample and a value represented by a sample immediately preceding the maximal-value-corresponding sample; fifth means for calculating a second difference between the minimal value represented by the minimal-value-corresponding sample and a value represented by a sample immediately preceding the minimal-value-corresponding sample; sixth means for calculating a first coefficient from the sample number detected by the second means; seventh means for calculating a second coefficient from the sample number detected by the third means; eighth means for multiplying the first coefficient and the first difference to generate a first multiplication result; ninth means for multiplying the second coefficient and the second difference to generate a second multiplication result; tenth means for incrementing the maximal value, represented by the maximal-value-corresponding sample, by the first multiplication result to modify the maximal-value-corresponding sample; and eleventh means for decrementing the minimal value, represented by the minimal-value-corresponding sample, by the second multiplication result to modify the minimal-value corresponding sample.