IMDCT optimization of AVS-P3 decoding algorithm in DSP

In order to write AVS-P3 audio decoding algorithms in the digital signal processor(DSP) chip which supports fixed-point algorithms, AVS-P3 audio decoding floating-point algorithms need to be converted to fixed-point algorithms. Owing to the high complexity of IMDCT(Inverse Modified Discrete Cosine Transform) module windowing in AVS-P3 decoder algorithm, we propose an improved windowing algorithm in this paper. The test results show that the time complexity of the module optimized is reduced by 17.04% and the space complexity of the module optimized is reduced by 32.9%. The proposed algorithm is better than the original algorithm in time and space performance.