B-spline filter banks for very low bit rate coding

Abstract

In this paper we report on the use of B-spline filters in perfect reconstruction filter banks. For each polynomial order the analysis and synthesis FIR filters are evaluated, considering the error introduced by filter coefficient truncation, coding quantization and the distortion introduced by the filters themselves. It is shown that B-spline filters exhibit higher energy concentration in the lower frequency band than other known filter kernels. This property can be exploited for very low bit rate image coding where the higher frequency bands might be very coarsely quantized. For a two channel subband coding system, the reconstructed image from the low frequency channel of the B-spline coder is compared with other filter banks reported in the literature. The simulation results show that B-spline filters achieve better reconstruction quality of images than their counterparts.