Evaluation of a Hybrid-Log 2D Wavelet Image Transform

This paper evaluates the use of hybrid-logarithmic number system (Hybrid-LNS) in the 2D forward and inverse discrete wavelet transforms (DWT and IDWT) by comparing the performance of the DWT and IDWT implemented with varying numbers of bits in a fixed binary point system, using both linear and Hybrid-LNS. Simulations were made with MATLAB^TM using Daubechies 9/7 filter coefficients. The results indicate that there is a significant improvement in both PSNR (greater than 10 dB) and the qualitative properties of the image when using Hybrid-LNS compared lo the equivalent linear implementation. The paper shows that by using multiplierless arithmetic techniques it is possible to build efficient, low-power and low cost solutions for the DWT and IDWT transform pair using custom ASIC or FPGA technology.