Speech spectrum representation and coding using multigrams with distance

The multigrams allow us to split a string of symbols into a stream of variable length sequences. The direct application of this method to vector-quantized speech spectra fails, we develop an extension of the method called modified multigrams or multigrams with distance. The algorithm for modified multigram dictionary training as well as experimental results are presented. We found a significant improvement of rate/distortion ratio in comparison to vector quantization with small codebooks. For precise spectrum representation, this method is less suitable and we see its application rather in speech segmentation or in very low bit rate coding.