Improving LZFG data compression algorithm

Summary form only given. This paper presents two approaches to improve the LZFG data compression algorithm. One approach is to introduce a self-adaptive word based scheme to achieve significant improvement for English text compression. The other is to apply a simple move-to-front scheme to further reduce the redundancy within the statistics of copy nodes. The experiments show that an overall improvement is achieved from both approaches. The self-adaptive word-based scheme takes all the consecutive English characters as one word. Any other character in the ASCII codes will be taken as one single word. As an example, the input message `(2+x) is represented by y´ can be classified into 9 words. To run the word-based scheme in PATRICIA tree, the data structure is modified