Fast matching pursuit method with distance comparison

Matching pursuit has been shown to be useful especially in low bit-rate video coding. However, one practical concern in its application is the massive computation required for finding dictionary elements. This paper provides a new method that can drastically reduce the computational load without any degradation of image quality. We use a simple distance comparison based on the Schwarz inequality to preclude a substantial number of dictionary elements without actually evaluating inner products. Experimental results show the number of inner product calculations about 20-30% of the separability-based method by Neff and Zakhor (see IEEE Trans. Circuits and Systems for Video Technology, vol.7, p.158-71, Feb. 1997)