Abstract: “This paper proposes two stage algorithm that carries advantages of PDLZW and Arithmetic coding and compares its performance with deflate which is a well-known two-stage algorithm that combines the features of LZ77 and Huffman Coding. The PDLZW is designed by partitioning the dictionary into several dictionaries of different address spaces and sizes. With the hierarchical parallel dictionary set, the search time can be reduced significantly since these dictionaries can operate independently and thus can carry out their search operations in parallel. Arithmetic coding replaces a stream of input symbols with a single floating-point output number”

Keywords: Arithmetic Coding, Lossless Data Compression, Lossy Data Compression, Parallel Dictionary LZW (PDLZW).