| 摘要 |
An entropy modifier 10, 60 encodes, and alternatively decodes, a stream of input data bits having a first entropy, generating corresponding modified output data having a second entropy. The entropy modifier (converter) which may be a pre-processor or post-processor for encoding 20 or decoding 50 stages - processes the stream of input data bits to handle groups of mutually similar bits (runs) and the value of a first (initial) bit, and one or more maximum run lengths of the groups of mutually similar bits, i.e. analogous to Run-Length Encoding (RLE) methods. The entropy modifier may control one or more maximum run lengths by using escape code(s), e.g. a code such as 0 used to denote a run of 3; maximum run length may be dynamically varied. A first, starting bit in the stream can be handled separately from other bits. Stream parts may be separately coded, in parallel. ODelta, RLE, Variable Length (VLC), Huffman, Delta or Arithmetic coding may be employed in conjunction with the initial / final entropy-changing processing. |
