Enhancement of LZAP (Lempel Ziv All Prefixes) Compression Algorithm

In this paper we proposed a dictionary based lossless data compression algorithm which is an enhanced version of LZAP. The compression process of the proposed method starts with an empty dictionary. The encoder will always try to find longest match. If there is no match, then the next character will be encoded with 9 bits. If a match is found, then it will be encoded with corresponding dictionary index. Here, the code length of the dictionary index will be determined by the code length of maximum dictionary index. The dictionary entries will be added in whole compression process. Whenever the dictionary gets full, it will remove all entries of the dictionary. Experimental results were performed and these results show that our proposed method performs better than other conventional compression algorithm like WinZip, Gzip, LZW, LZAP etc. when the file size is greater than one Megabyte.