Ladder realizations of fast subband/VQ coders with diamond support for color images

A ladder implementation of a subband/vector quantization (VQ) coder is presented. The ladder realization significantly reduces the number of computations required to achieve the desired decomposition, compared to the separable system presented by R.E. Van Dyck and S.A. Rajala (see Proc. IEEE Visual Sig. Proc. Conf., p. 235-240, 1992). In this system, the low-pass subimage has a diamond orientation in order to more closely match the orientation of the human visual system. The reduction in computations is given, and coding results for color images are presented for different color spaces.<
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