Image encoding method and image encoding device

Abstract

The invention discloses an image encoding method and an image encoding device. The method comprises the following steps: dividing domain blocks according to a value block scale range; performing isomorphic transformation on a matrix composed of 4 low frequency coefficients obtained by performing wavelet transformation on the domain blocks; performing recursive partitioning on value blocks until scale of the value blocks is less than the maximum scale; performing wavelet transformation on the value blocks to obtain 4 low frequency coefficients, calculating a value block direction K1 and a domain block direction K2, calculating a luminance factor and a shift factor and error thereof if the K1 is identical with the K2, and judging if the error is less than 5; if yes, writing position information of the value block and the domain blocks, transformation information and value block scale information into a code stream file, or performing quadtree partitioning on the value blocks; and writingending information into the code stream file when all the value blocks find corresponding domain blocks. The invention accelerates encoding speed and effectively improves compression ratio and decoded image quality, thus realizing effective image compression.

Description

technical field [0001] The present invention relates to image compression technology, in particular to an image encoding method and an image encoding device. Background technique [0002] The development of remote sensing technology makes the amount of remote sensing data expand rapidly, which brings inconvenience to the storage and transmission of remote sensing data. It is usually necessary to adopt effective coding technology to compress the amount of remote sensing data. Fractal coding technology and wavelet coding technology are the new generation coding technology, and are the main direction of still image coding research at present. The fractal coding theory was proposed by Mandelbrot in the 1970s. After continuous development and evolution, Fisher proposed a new image division method in fractal coding in the mid-1990s. He divided the given domain block and value block into four The whole image is divided into 72 categories according to the average value and variance...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to provide an image encoding method and an image encoding device to solve the problems of slow encoding speed, low image compression ratio, or low decoded image quality in image compression, so as to improve the comprehensive performance of image encoding, so that at the same time Achieve faster encoding speed, higher compression ratio and higher decoded image quality

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