Research On Data Compression Technology

With information society's development, people have to process each kind of huge image data and text data every day. The image receives people's favor by its superiority of direct-viewing and becomes the main way that humanity gain information. In recent years, it's urgent to find the highly effective compression method because of the image data's quantity magnanimous growth.At present the mature data compression technology has many kinds, according to the compressed information's distorted degree, mainly divides into lossless compression and loss compression.It's urgent to own the highly effective lossless compression method because of data fidelity request in domain such as medicine, security and remote sensing. This paper proposes image lossless compression algorithm based on the improved LZW summarizing many kinds of lossless compression algorithm.This method takes the static picture as the main studyed object,which is simulated and confirmated on Visual Studio 2005 platform.Firstly,it introduces data compression's elementary theory and the image related knowledge, as well as the standard of weighting compression effect, and has made the brief outline to the main lossless compression method. Then,it analyzes several encoding method and further compares these algorithm's characteristics. These algorithm is mainly lossless compression, including Huffman coding, Arithmetic coding, run-length coding and dictionary coding.Secondly,it analyzes the modern dictionary compression algorithm emphatically, including LZ77, LZ78 and LZW and so on LZW algorithm is revision form based on the LZ78 algorithm,which is widely used and a kind of techonolgy of compactest at present. But this traditional code process's deficiency lay in both has wasted the memory space, and increased the processed time.Finally, the paper proposes one kind of advanced LZW compression algorithm based on the dictionary compression method's research and analysis,to solve bad compression effect of the traditional LZW method at initial period of establishing dictionary. The C# language is one kind of object-oriented programming language, can be programed which is more structurized, the modulation,with heavy responsibility,expanding and easily maintained. We may program algorithm using the C# language, operating procedure algorithm in the Visual Studio 2005 environment,and further study and compare each algorithm. The experimental result indicated that the improved LZW algorithm's compression ratio has certain enhancement compared with the traditional algorithm.