| 摘要 |
<p>PURPOSE:To reduce the number of times of distance calculation and to speedify the quantization by calculating the distance dij between code book vectors yi and yj, and deciding whether a calculation is necessary or not for the matching between an input vector (x) and another code book vector yj by using the distance di between the input vector (x) and the code book yi. CONSTITUTION:The code book vectors yi, yj are generated by a code book vector generation part 2. An input vector (x) is inputted to a distance calculation part 4, and the distance di between the input vector X and the code book vector yi is calculated by a calculation part 5, and the result is stored in a memory 6. Also, the surfix (i) of the code book vector yi is stored in a memory 7. Prior to the distance calculation of the (x) and the yj, the distance dij between the yi and the yj is preliminarily inputted from an inter-code book vector distance table 3 to a distance calculation admission/prohibition circuit 8, and dij/2 is calculated. Thereafter, the value d1 stored in the memory 6 and the dij/2 are compared with each other. If the relation di>dij/2 does not satisfied, the distance calculation of the yj and xj is eliminated.</p> |
