Video image coding/decoding method based on geometric partitioning

Abstract

The invention discloses a video image coding / decoding method based on geometric partitioning. The coding method comprises the following steps: firstly, a video image is partitioned into a plurality of rectangular coding blocks, and the rectangular coding blocks are geometrically partitioned; secondly, motion estimation is carried out for each geometrically partitioned irregular block, each irregular block obtains an own residual block, and the residual blocks corresponding to the irregular blocks are combined to a rectangular residual block; thirdly, the coordinates of pixels in the rectangular residual block are rearranged by utilizing geometrically partitioned boundary direction information; and lastly, two-dimensional orthogonal transformation is carried out for the rearranged rectangular residual block, a transformation coefficient is quantized and entropy coding is processed, in addition, geometrically partitioned information and rearranged information are incorporated into a code flow. The decoding process and the coding process are inverse. Since the geometrically partitioned boundary direction information is utilized and the pixels of the rectangular residual block are rearranged when the coding is processed, so that after orthogonal transformation, a high-frequency nonzero coefficient is reduced, and compression efficiency is improved.

Description

technical field [0001] The invention relates to a method for encoding and decoding video images, in particular to a method for encoding and decoding video images based on geometric segmentation. Background technique [0002] The existing video coding standards all use the regular block segmentation method for inter-frame motion estimation and motion compensation. The regular block segmentation has a simple structure and is easy to implement. In particular, the latest video standard H.264 uses a smaller block size (4x4) to describe the boundaries of moving objects, which greatly improves the accuracy of motion estimation. However, the block boundaries of the regular block segmentation model are based on the horizontal and vertical directions, which cannot describe the complex and changeable boundaries of moving objects in natural images. [0003] Traditional video coding such as MPEG1 and MPEG4 uses 8x8 two-dimensional discrete cosine transform (2-D DCT), which eliminates th...

AI Technical Summary

Problems solved by technology

After the geometric segmentation block is motion compensated, the residual is more concentrated on the segmentation boundary. After the traditional two-dimensional orthogonal transformation, more high-frequency non-zero coefficients will be generated, which limits the improvement of compression efficiency.

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