| 摘要 |
Apparatus and method for quantizing and entropy encoding transform coefficients in the encoding of multimedia data, for example video and audio data. Pixel value data is input into a decorrelator, 302. The decorrelator generates reduced transform coefficients. A quantizer 304, for example a bit plane slicer, is used to remove irrelevant data from the reduced coefficients. Statistical dependencies in the bit planes are exploited by the application of a context selection means 308, which in turn generates multilevel context paths. The multilevel context paths are input into an entropy encoding mechanism 310. In one embodiment, the entropy encoding mechanism comprises: a run-length pre-coder 312, for receiving input data at each context level and outputs run-length symbols; and an analytical entropy coder 314, which receives the symbols and generates a compressed data stream. The above stages are reversed in decoding. |
