| 摘要 |
A method and apparatus are disclosed for compressing data and especially for identifying one codebook vector in a vector quantizer which best matches an input data vector. The steps of the method include: (i) calculating the value of a characteristic measure for the input vector; (ii) identifying a reference codebook vector, Aj, having a value of a norm which is closest to the norm of the input vector; (iii) computing a distance, hi,j, between the input vector and the reference codebook vector Aj; (iv) identifying a subset, S, of codebook vectors for which a measure of codebook vectors of the subset S satisfies a criterion; and (v) selecting a codebook vector from the subset S which closely matches the input vector. Several criteria for forming the subset S are shown, including selecting codebook vectors having norms in a range about the input vector's norm, and having a distance to the reference codebook vector which is less than a calculated value. |
