| 摘要 |
A multistage data compression system includes an encoder for receiving input data sequences from a data source, where the encoder comprises two or more quantizer stages, each stage having a memory for storing an established set of codewords preselected such that the sum of different combinations of codewords, one for each stage, is representative of likely to occur input data sequences. Each codeword of each stage has a respective index associated therewith. The encoder operates to select a codeword from at least two of the stages such that the sum of the selected codewords is a closer match to each input sequence than any other sum of codewords formed from the selected stages. When the codewords of interest are determined, the indices of those codewords are retrieved. These indices may then be transmitted to another location, stored in memory or otherwise processed. The system also includes a decoder coupled to the transmission channel, memory, or other mechanism which operates on the indices. The decoder includes a decoder memory for storing the established sets of codewords with respective indices, a retrieval device for retrieving from the decoder memory the codewords whose respective indices were transmitted, stored or otherwise processed, and a summing mechanism for adding the retrieved codewords to produce a reproduction data sequence representing an approximation of a corresponding input data sequence.
|
