Arithmetic coding decoding method implemented by table look-up

Abstract

This invention discloses a count encoding and decoding method achieved by form detecting. This method is an effective method to compress and uncompress the data of unequal probability. The process needs constant segmentation of lines. Because in the condition of limited precision, so the unlimited segmentation is not realistic and it reduces the amplifying and moving of the line, which is the updating. The updated information is the output encoding code. Update Value at the decoding end. This invention judges the positions of the two ends of the front line to get index information of 'data form', the updating line and finish other operations. It greatly saves the calculation amount of encoding. Although this invention increase the storage space to store 'data form', it greatly speeds up the calculation and improve the hardware efficiency.

Description

technical field

[0001] The invention belongs to the technical field of data compression, and in particular relates to an arithmetic encoding and decoding method realized by looking up a table. Background technique

[0002] Arithmetic coding is a lossless coding method, which can effectively compress the source redundancy. It is a kind of entropy coding, and is suitable for the compression of non-equal probability data. The basic principle of arithmetic coding is: according to the probability of different symbols in the encoded data, the line segment is divided into non-overlapping sub-line segments, and the width of the sub-line segment is exactly the probability of each symbol. Encoding a symbol is to find the corresponding sub-line segment, and then divide the line segment to obtain sub-line segments of the next level, and encode the next symbol. Any real number in the last sub-line segment can be used to represent the corresponding symbol sequence, and this number is the...

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