Encoding method of conversion coefficients, decoding method of conversion coefficients and device

Abstract

A method and an apparatus for encoding and decoding transform coefficients are disclosed. The encoding method includes: encoding transform coefficients of a transform coefficient block according to a predetermined scan order, and encoding a set number of transform coefficients in each group until a last group of the transform coefficient block is encoded; storing an obtained map of non-zero transform coefficients, absolute values of transform coefficients, and positive and negative signs of non-zero transform coefficients; when the last group is being encoded, after obtaining a map of non-zero transform coefficients encoded in the last group, encoding the stored map of non-zero transform coefficients and the map of non-zero transform coefficients encoded in the last group into a bit stream; and after obtaining absolute values of transform coefficients and positive and negative signs of non-zero transform coefficients encoded in the last group, encoding the stored absolute values of transform coefficients and positive and negative signs of non-zero transform coefficients and the absolute values of transform coefficients and positive and negative signs of non-zero transform coefficients encoded in the last group into the bit stream. Encoding and decoding efficiency can be increased.

Description

technical field [0001] The present invention relates to the technical field of video processing, in particular to a method for encoding transform coefficients, a method for decoding transform coefficients, and a device. Background technique [0002] Currently, entropy coding in video coding technology mainly adopts run-length coding and arithmetic coding. For example, context-based variable length coding (Context Adaptive Variable Length Coder, CAVLC) and adaptive binary arithmetic coding (Context Adaptive BinaryArithmetic Coder (CABAC) two kinds of entropy coding, these two entropy coding modes make full use of the correlation between the coded information and the current coded information, specifically: use the coded information to construct the code table or probability model of the current coded information, This is called context-based entropy coding. Because CABAC adopts the idea of ​​arithmetic coding, its coding performance is better than that of CAVLC, but correspo...

AI Technical Summary

Problems solved by technology

Due to the above-mentioned scanning sequence is different, it is necessary to execute the reading data once in the encoding process of executing step A and executing B~D respectively, and the decoding end also needs to solidify two table lookup methods corresponding to these two sequences, resulting in high encoding and decoding efficiency overhead. low efficiency

In addition, in step A, if the transform coefficient block is relatively large, usually called a large transform unit, for example, the 32×32 significance map will be relatively large, so the burden of encoding a large significance map in hardware design is relatively large

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