Multi-stream audio sampling rate conversion system and method using variable converter rate control data

摘要

A sample rate conversion system and method uses a digital signal processor (DSP) and a separate sample rate conversion circuit (SRC) to perform multiple stream conversion and mixing of different rate input audio streams. The sample rate conversion system converts data, such as multiple streams of digital audio data sampled at different rates, and performs interpolation, decimation, FIR filtering, and mixing of multiple streams of data using the separate SRC. The SRC uses two bidirectional I/O memories for alternately storing input and output data as part of a sample rate converter. When the sample rate converter writes output to one of the bidirectional memories, it has the option of summing the data with the data already stored in the same I/O memory. Therefore a separate digital signal processor can use the sample rate converter circuit to perform some of the mixing for the multiple streams.