A LATTICE VECTOR QUANTIZATION USING A GEOMETRIC DECOMPOSITION

An efficient lattice vector quantization design and the associated fast coding algorithm is proposed in this paper for high-bit-rate, high-quality data compression applications. The codewords are uniformly distributed and densely packed as 2n -dimensional lattice points, based on a geometric lattice decomposition technique. The maximum quantization error has been chosen as the design criterion. For high-rate applications, it has the following advantages: 1) simple vector codeword generation; 2) no codewords need to be stored and only predetermined rules are used at encoder and decoder ends; 3) highly regular code structure, so that encoding is done via an inverse tree-search suitable for fast parallel processing, and decoding is done similar to a scalar quantizer; 4) high coding quality capability, viz. the maximum quantization distortion can be prespecified to a desired value and the entire hyper-region is covered uniformly; 5) “dimensionality saving” can be easily predicted and it can be achieved using fixed-length codes. © 1990 IEEE