Adaptive splitting threshold for vector quantization

The LBG algorithm for obtaining the initial codebook uses a splitting technique. The splitting process is performed by adding a fixed perturbation vector e to the main vector y, leading to the two vectors y+e and y -e . Unfortunately, the choice of the perturbation vector requires exhaustive research of the optimal value of this parameter leading to minimal distortion. An automatic and adaptive choice of this parameter is described. Experimental results are presented. Simulations show that this procedure gives at least the same distortion as when the choice `is performed optimally offline