摘要 |
The invention is a method, apparatus and computer readable program for eliminating overflow and underflow by re-adjusting or rectifying the audio levels of an audio signal in those portions where overflow/underflow occurs.In a first preferred embodiment a single stage scale down solution is provided in starting and end points of the overflow/underflow areas in the audio signal are detected, and a number of discrete sampling points along the audio signal curve between these two points are adjusted by a predetermined multiplier in order to reduce the positive level (in the case of overflow) or negative level (in the case of underflow) of each discrete sampling point. Using the single stage scale down solution of the present invention, a new audio signal is created having no overflow/underflow, yet maintaining the former generally smooth shape of the audio signal waveform and signal characteristics, without completely clipping the audio levels.In a second preferred embodiment a multi-stage scale down solution is provided in which the overflow/underflow is divided into sections, such that the discrete sampling points in one section may be adjusted by a first multiplier in order to reduce their audio levels; while discrete sampling points in another section may be adjusted by a second multiplier (which is preferably different than the first multiplier) in order to reduce their audio levels. Accordingly, a new audio signal is constructed with reduced overflow/underflow, yet maintaining a generally smooth signal curve and characteristics, without completely clipping the audio levels.
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