Optimized video data coding method based on boundary adaptive transform

Abstract

The invention provides an optimized video data coding method based on boundary adaptive transform. The method mainly comprises steps: according to the existing DCT (Discrete Cosine Transform) matrix for video coding, a new transform matrix is generated, the new transform matrix and the existing DST (Discrete Sine Transform) / DCT matrix are combined into a new transform matrix set; according to a prediction mode, the size of a transform unit, and the relationship between the boundary information of a transform unit and the boundary information of a prediction unit, a group of transform matrixes is selected from the new transform matrix set; and by using the group of new transform matrixes, inputted video data are transformed, and a coding stream is generated. The method of the invention makes full use of distribution characteristics of residual matrixes after inter-frame prediction, and based on the boundary information of the prediction unit and the transform unit, a different transform matrix is adopted for a different boundary characteristic to carry out transform. The optimized method can select a more efficient transform matrix for transform in a targeted mode according to the characteristics of residuals after inter-frame prediction, and the coding efficiency is thus improved.

Description

technical field [0001] The invention relates to the technical field of video coding and decoding, in particular to an optimized video data coding method based on boundary adaptive transformation. Background technique [0002] Since the H.261 video coding standard, mainstream video coding standards have adopted a hybrid coding framework of "block-based prediction and transformation". figure 1 It is a general frame diagram of a video codec in the prior art. After the input video signal is processed by multiple encoding techniques in the encoder, the bit stream is finally output for the decoder to decode. Therefore, under the framework of hybrid coding, a complete video codec system includes two parts: encoder and decoder. [0003] figure 2 It is a basic flow chart of video encoding in the prior art, including the following process; at the encoding end, the input video signal first passes through the prediction module, and the encoder selects the optimal one from several pre...

AI Technical Summary

Problems solved by technology

[0010] Although the existing technologies in HEVC and AVS2 can use different transformation matrices for intra-frame coding, they do not take into account the statistical characteristics of the residual distribution of inter-frame coding, and the large DST transformation matrix of HEVC and the secondary transformation in AVS2 The implementation is computationally expensive, and once used will greatly increase the complexity of the codec

Therefore, the existing transformation technology has limited improvement in encoding performance under low-delay (LowDelay) and random access (RandomAccess) configurations.

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