Method for decoding video and apparatus therefor and method for encoding video and apparatus therefor

Abstract

Disclosed is a method for decoding video, comprising: determining a scan area containing all of effective transform coefficients in a current block; scanning information on the transform coefficientsin the scan area according to a predetermined scan order; performing binary arithmetic decoding on the basis of information on the scanned transform coefficients to generate binary arithmetic decodedinformation; performing inverse binarization on the binary arithmetic decoded information to obtain the information on the transform coefficients of the current block; performing inverse quantizationand inverse transform on the basis of the information on the transform coefficients of the current block to generate a residual block of the current block; and restoring the current block on the basisof the generated residual block. According to the disclosed video decoding method, the binary arithmetic decoding may be performed by using a context model determined on the basis of at least one ofthe size and the shape of the current block.

Description

technical field [0001] It relates to a video decoding method and a video encoding method. More specifically, entropy decoding and entropy coding are involved. Background technique [0002] With the development and popularization of hardware capable of playing and storing high-resolution or high-quality video content, there is an increasing demand for video codecs that efficiently perform encoding or decoding on high-resolution or high-quality video content. According to existing video codecs, videos are encoded with limited encoding methods through tree-structure-based coding units. [0003] Image data in the spatial domain is transformed into coefficients in the frequency domain by using a frequency transform. A video codec divides an image into blocks having a predetermined size, and performs encoding of frequency coefficients in block units by performing discrete cosine transform (DCT) for each block to perform fast operation of frequency transform. Compared to image d...

AI Technical Summary

Problems solved by technology

In particular, since image pixel values ​​in the spatial domain are represented as prediction errors by inter prediction or intra prediction of the codec, many data may be transformed to zero when frequency transformation is performed on the prediction error

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