Intra-frame prediction method

Abstract

The invention relates to an intra-frame prediction method, which increase the intra-frame prediction compression efficiency and comprises the following steps: (1) a brightness intra-frame prediction processing unit is selected according to the image coding frame size; (2) the sizes and the prediction modes of a brightness intra-frameprediction subblock and a chroma intra-frame prediction subblock are selected respectively; (3) the intra-frame prediction is performed according the selected sizes and the prediction modes of the brightness intra-frame prediction subblock and the chroma intra-frame prediction subblock to obtain an intra-frame prediction sampling value and a residual error of the intra-frame prediction subblocks;and (4) the coding mode of the intra-frame prediction subblocks, the brightness intra-frame prediction mode as well as the chroma intra-frame prediction mode and the residual error are coded respectively and then are sent to a code stream. The classification of the intra-frame prediction method is mainly aimed at the circumstances that the sizes of the intra-frame prediction subblocks are 4*8, 8*4, 8*16 and 16*8, and five optional prediction modes are matched, so that 3 percent to 5 percent of code stream bandwidth is saved under the condition that the image quality is identical, and the image encoding compression efficiency is increased; and the effect of simplifying the computational complexity can be also achieved due to the selection of partial prediction modes.

Description

technical field [0001] The present invention relates to an intra-frame prediction method used when performing image encoding or decoding, and more specifically, relates to an intra-frame prediction method capable of improving the compression efficiency of intra-frame prediction. Background technique [0002] Digital video compression coding technology is a technology for compressing and decompressing digital video signals. An important means of video compression is to remove spatial redundancy and time redundancy. The technology of removing spatial redundancy is also called "intra-frame prediction technology", which can improve the coding efficiency of intra-coded macroblocks. Before the appearance of the H.264 video standard, the existing coding standards performed intra-frame prediction in the frequency domain, such as MPEG-2 DC coefficient (DC) differential prediction, MPEG-4 DC and high frequency coefficient (AC) predict. The H.264 video standard proposes intra-frame p...

AI Technical Summary

Problems solved by technology

[0004] The technical problem to be solved by the present invention is to propose an intra-frame prediction method suitable for rectangular prediction sub-blocks in view of the limitation of the size of the prediction sub-block in the intra-frame prediction of the existing H.264 video standard and AVS video standard

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