Data compression is one of the most important areas of computer science. It enables devices to transmit data with fewer bits (saving time and storage space).
In this project, the two crucial lossless data compression algorithms (Huffman coding and LZW coding) were investigated and implemented. For Huffman coding program, the entropy (information redundancy), compression ratio and compression time based on different user defined bit lengths have been discussed. An optimum method which can potentially improve the compression ratio has been proposed. For LZW coding program, the entropy, compression ratio and compression time have been discussed as well. Design of how to choose these two algorithms based on different circumstances have been discussed.
Key words: data compression, Huffman coding, LZW coding, entropy, compression ratio, compression time.