Size-reducing decoding method and system

Abstract

The invention discloses a size-reducing decoding method and a size-reducing decoding system. The method comprises the following steps: acquiring a motion vector and a DCT coefficient matrix of a preliminarily decoded macro block by carrying out variable length decoding and inverse quantization of a to-be-decoded macro block; acquiring a second DCT coefficient block and a third DCT coefficient block by carrying out the low-pass filtration of a first DCT coefficient block in the DCT coefficient matrix; acquiring a first reference macro block, a second reference macro block and a third referencemacro block by carrying out inverse DCT transformation of the first, second and third DCT coefficient blocks; according to a required reduced size, calculating the pixel values of pixel points in a reduced-size macro block by means of the pixel values of pixel points in the reduced-size macro block at the mapping points of two of the first, second and third reference macro blocks; and carrying out motion evaluation and motion compensation of the size-reduced macro block by means of a prestored reference image and motion vector acquired through decoding the motion vector of the preliminarily decoded macro block and reducing the decoding result according to the required reduced size.

Description

technical field [0001] The present invention relates to video processing technology, and more particularly relates to a size reduction decoding method and system. Background technique [0002] MPEG-2 downsizing decoding is the process of decoding MPEG-2 format streams into downsized videos, which can be applied to mobile devices (eg, car navigators, mobile phones, etc.) to play videos of appropriate sizes. The Down-Decoder is a decoder for terrestrial broadcast receivers. Considering the actual hardware implementation, the Down-Decoder is designed with the goal of low power consumption and low cost. [0003] "Discrete Cosine Transform (Discrete Cosine Transform, DCT) coefficient low-pass filtering" is a process of retaining only the low-frequency part of the DCT coefficient matrix in order to directly obtain the required size of the macroblock through the inverse DCT transformation while avoiding the transition loss of image precision . "Size-reduced inverse DCT transform"...

AI Technical Summary

Problems solved by technology

However, since this method / system needs to apply a multi-tap filter for filtering, it will result in a lot of calculations, resulting in a slowdown of downsizing decoding, larger required computing resources, etc.

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