Earticle

Linde–Buzo–Gray (LBG) algorithm is a universal method to design codebook in vector quantization(VQ). This paper proposed an adaptive orthogonal M-split initialization method to improve the computational efficiency of LBG algorithm. The method splits one code word into 2, 4 or 5 new code words with adaptive split coefficient vectors and set the increment to be orthogonal in 4-split and 5-split situations, aiming at decreasing the iterations of the following clustering. Experiment is conducted on both TIMIT and RASC863 speech database, which shows that the proposed algorithm provides a reduction of 18%~45% in designing codebook in size of 64~2048 with almost equal VQ performance, compared with the universal codebook generation algorithm.

In this paper, we propose a new method for reducing the number of distance calculations in the LBG (Linde, Buzo, Gray) algorithm, which is widely used method to construct a codebook in vector quantization of speech recognition system. The proposed algorithm can reduce the distance calculation between input vector and codeword by utilizing the observation that codewords are quickly stabilized as the number of iteration increases. From the simulation results, it is shown that we can reduce the running times over $43.77\%$ on average in comparison with current LBG algorithm without sacrificing the performance of codebook.