Block-wise adaptive statistical data compressor

摘要: A block-wise adaptive statistical data compressor is disclosed that operates by replacing characters in a block with super-character codewords comprising variable length prefix and fixed index. The are determined treating plurality of groups as then adapting the codewords, for each block, based upon actual frequency occurrence group. value identifies group to which particular character belongs, index individual By grouping indexing into these groups, present invention models using fraction information generally required compressor. Also multi-stage lossless compressors include also clustering stage reordering stage. clusters like similar locations within reorders generate an expected skew distribution so can be more efficiently compressed