Matched block transform design techniques

In this work, two new design techniques for matched (adaptive) orthogonal block transforms (BT) based partly on Vector Quantization (VQ) are presented. Both techniques start from reference vectors that are adapted to the characteristics of the signal to be coded. Then the corresponding orthogonal block transform is obtained in the first technique via signed permutations of the reference vector, while in the second technique an optimization search in the null space of the reference vector is executed. The resulting transforms represent a signal coding tool that stands between a pure VQ scheme on one extreme and signal independent fixed block transformation like DCT on the other.