Research And Implementation Of Fast Decompression Algorithm

Data compression technology has been researched by people because of its important role in the information technology.The purpose of data compression is using little data to represent as much information as possible,thus to increase the transport speed and decrease the storage space of the information.Every compression algorithms have its characteristics.Some algorithms is simple in principle,and cannot get high compression ratio but its small and compact suitable to the embedded systems.Some algorithms complexity in principle and has high compression ratio suitable to the PC systems.In the course of communication,data compression can increase the transport speed.But when the receiver's decompression rate is less than data receive speed,decompression rate become a bottleneck and congestion starts to happen.We must reduce the transport rate or cache data on the receiver.But not all receivers has enough cache to cache data.The fast decompression algorithm is a powerful solution in this case,it can improve the user experience.This is why LZO algorithms widely used nowadays.Especially in some condition such as the data be compressed one time and be download and decompressed by many users,the time consumption of compress is low,the fast decompression algorithm can save data flow and time.In this thesis,based on the analysis of lossless compression algorithms,design and implement a fast decompression algorithm.This thesis mainly completes these following works:1.The most representative lossless compression algorithms at home and abroad are introduced,such as LZ77?LZ78?LZSS and LZW,and analyzing the LZO algorithm particularly.2.Based on analyzing the principle of the LZO's fast decompression,a new compression algorithm was designed which can decompress data faster than LZO.The new compression algorithm optimizing the compress method and storage format of LZO.3.Because the data overflow and program collapse may happen when decompress error data.We analyzing the problem in this paper,and solve it in the new compression algorithm.4.The software development of the new compression algorithm has been completed,including development of program in Windows operate system and transplant the program to DSP.5.The function and performance of the new compression algorithm has been tested.The test results shows that the decompress speed has been enhanced prominently than LZO.