Unlock instant, AI-driven research and patent intelligence for your innovation.

Method for compression and decompression of lossless bitmap

A compression method and decompression technology, applied in the direction of image communication, electrical components, etc., can solve the problems of high compression, no support for bitmaps with more than 256 colors, and unsatisfactory support for irregular jitter, so as to improve the compression ratio, avoid Effect of saturation overflow problem

Inactive Publication Date: 2010-11-17
BEIHANG UNIV
View PDF4 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

This compression method has relatively high image compression, and can achieve lossless compression in some cases, but the support for irregular jitter is not ideal, a large number of repetitive structures appear in images with high compression ratios, and bitmaps with more than 256 colors are not supported

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for compression and decompression of lossless bitmap
  • Method for compression and decompression of lossless bitmap
  • Method for compression and decompression of lossless bitmap

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0044] The present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0045] The lossless bitmap compression and decompression method of the present invention adopts the combination of generalized color block coding and differential transformation to realize the compression and decompression process with high compression ratio.

[0046] All "images" in this embodiment refer to digital bitmaps, the abscissa is X, from left to right, and the ordinate is Y, from top to bottom, counting from 0, expressed as (X, Y).

[0047] The compression process of lossless bitmap of the present invention is as figure 1 As shown, the specific steps are as follows:

[0048] (1) Do generalized color block coding on the original image, and record its compression ratio C 0 ;

[0049] (2) Specify the number of differential transformations as 1

[0050] (3) Perform differential transformations of the specified number of times on t...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention provides a method of compressing and decompressing non-loss bitmaps, wherein the compression process comprises the following steps of: carrying out generalized colour block coding to original images, and recording compression ratio CO thereof; increasing difference times, respectively carrying out difference transform to images by means of transverse and vertical priorities for eachdifference time; carrying out generalized colour block coding to the transformed result, recording and comparing the compression ratios till the difference transforms corresponding to two adjacent difference times are the same; and writing the corresponding difference transform modes and the data of images after the generalized colour block coding into files by selecting the transform mode and transform process with the highest compression ratio; corresponding decompression process comprises: carrying out generalized colour block decoding to the data of images; and restoring images by difference inverse transform according to the recorded times by means of recorded transverse or vertical preferred mode, based on the recorded difference transform mode. The method provided by the invention well supports irregular flutter on the basis of non-loss compression, without additional demands for colour and depth.

Description

technical field [0001] The invention relates to a digital image processing method, in particular to a digital image compression and decompression method. Background technique [0002] Digital image is an important information carrier at present, and its application is very extensive. Most of the computer directly acquires digital bitmaps. After effective compression and reduction of volume, the space efficiency of image storage and the bandwidth efficiency of transmission can be improved. [0003] Currently the most common digital bitmap compression modes are JPEG and GIF. JPEG cannot provide lossless compression; GIF has a limit of 256 colors, and the support for irregular jitter is not ideal. [0004] The JPEG compression method is to linearly transform the image color information into saturation information, then perform DCT (discrete cosine transform) on each component, discard high-frequency items as needed, and finally perform RLE (run-length encoding) on ​​the freque...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Patents(China)
IPC IPC(8): H04N1/413H04N1/41
Inventor 祝世平王宇辉郭丰
Owner BEIHANG UNIV