Multi-step audio object coding and decoding method based on two-stage filtering

Abstract

The invention discloses a multi-step audio object coding and decoding method based on two-stage filtering. In the coding stage, firstly, a plurality of input audio object signals are subjected to time-frequency transformation; an object circulation down-mixing sequence is determined, side information of each step is extracted, and a final down-mixed signal is output; redundant components which cannot be perceived by human ears in the residual information are removed through a first-stage filter; residual errors in the first n sub-bands are reserved through a second-stage filter according to the energy size of residual error information in each sub-band; singular value decomposition is carried out on the residual information after secondary filtering, and a large-size residual matrix is compressed into a small matrix; and the final mixed signal, the parameter and the residual decomposition matrix are synthesized into a code stream. In the decoding stage, the decomposed residual matrix is firstly utilized to reconstruct the original residual, and then multiple objects are gradually stripped from the down-mixed signal according to the side information. According to the method, secondary components in residual information are filtered out by using psychoacoustics and sub-band energy information, and the coding rate of the audio objects is reduced.

Description

technical field [0001] The invention belongs to the technical field of digital audio signal processing, and specifically relates to a multi-step audio object encoding and decoding method based on two-stage filtering, which is suitable for multi-audio object signal transmission under the condition of limited code rate, and allows transmission under different code rate requirements residual information. Background technique [0002] Next-generation audio systems differ from previous systems in two ways: immersion and personalization. For immersion, spatial audio technologies such as MPEG Surround [Document 1] and NHK 22.2 [Document 2] can provide three-dimensional audio reproduction. For personalization, the audio system should be compatible with different playback environments and devices according to user needs. In addition, the personalized audio system should support interactive audio services. But traditional spatial audio content is delivered to all users, regardless ...

AI Technical Summary

Problems solved by technology

[0012] In order to solve the problem of high coding rate of multi-step audio objects, the present invention provides a multi-step audio object coding and decoding method based on two-stage filtering, which can perform high-quality audio coding and decoding at medium and low bit rates, ensuring that all Audio objects all have good decoded sound quality

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