System and method for providing high-quality stretching and compression of a digital audio signal

A method for temporal modification of segments of an audio signal including speech, comprising:

• sequentially extracting data frames from a received audio signal;
• determining a content type of each segment of a current frame of the sequentially extracted data frames, said content types including voiced segments, unvoiced segments, and mixed segments;
• temporally modifying at least one segment of the current frame by automatically selecting and applying a corresponding temporal modification process for the at least one segment of the current frame from among a voiced segment temporal modification process, an unvoiced temporal modification process, and a mixed segment temporal modification process;
• and
• determining whether an average compression ratio of temporally modified segments corresponds to an overall target compression ratio, and wherein a next target compression ratio for at least one next current frame is automatically adjusted as needed for ensuring that the overall target compression ratio is approximately maintained.

A computer-implemented process for providing dynamic temporal modification of segments of a digital audio signal, comprising using a computing device to:

• receive one or more sequential frames of a digital audio signal;
• decode each frame of the digital audio signal as it is received;
• determine a content type of segments of the decoded audio signal from a group of predefined segment content types, each segment content type having an associated type-specific temporal modification process, wherein the group of predefined segment content types includes voiced type segments and unvoiced type segment;
• modify a temporal scale of one or more segments of the decoded audio signal using the associated type-specific temporal modification process specific to each segment content type;
• wherein modifying the temporal scale of one or more segments comprises any of temporally stretching and temporally compressing the one or more segments to approximately achieve a target temporal modification ratio and
• wherein the target temporal modification ratio of subsequent segments is automatically adjusted to achieve an average target temporal modification ratio relative to actual temporal scale modification of at least one preceding segment.