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AVS audio standard with independent intellectual property rights, as the second generation source coding standards, it provides a highly efficient technical program of coding and decoding for digital audio equipments and systems, it’s a moderate choice during algorithm performance and complexity for practical applications.Currently, AVS audio standard has just released, in other country, the AVS standard is limited to tracking, most of work is carried out by domestic research institutions, and focused on the implementation of decoder, the study for coding part is not sufficient. In this paper, in-depth research and analysis is done for the AVS audio coding standard, and it will contribute to the promotion and application of the standard. So, it has some practical significance.First, this paper carefully analyzes each module of the AVS audio standard from the aspects of coding framework, algorithm theory and calculation steps. Next, for the temporary steady-state decision and pre-echo control, further analysis and research are carried out and the current common algorithms of them are discussed here. Then, a transient signal detection algorithm based on peak average power ratio is proposed, which uses the characteristic of mutation rate in time domain, comparing with other frequency domain detection algorithm, it has the feature of low complexity, high time resolution and high accuracy. At last, the author proposed a transient signal processing method which is based on flattening in time domain, it uses a trigonometric function to multiply with the transient signal, so the signal will tend to flat, then using the method of coding stationary signal to encode the transient signal. The experimental results show that the new algorithm can get a good coding performance with low computational complexity, so it can replace the multi-resolution analysis technique which is used in AVS audio stardard.
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