Finite word length effects on two integer discrete wavelet transform algorithms
a ITB Research Center on Information and Communication Technology DSP-RTG, Information Technology Research Division School of Electrical Engineering and Informatics, ITB Microlectronic Center, Institut Teknologi Bandung, Indonesia
Abstract
This paper studies finite word-length effects on two different VLSI architectures of integer discrete wavelet transforms (DWT). The two DWT architectures representing two extreme cases are Scheme 1: basis correlation, and Scheme 2: pyramidal algorithm. For signal-to-noise ratio (SNR) evaluations, we consider various values of the length of integer word (W). Our experiments show that W is critical for both schemes, although both schemes perform almost equivalently. We also show that Scheme 1 and Scheme 2 have computational complexities O(N2) and O(N), respectively. The paper concludes that the word length W has similar critical impacts on the quality of integer DWT of both Schemes, hence Scheme 2 should be used based on lower computational complexity reason.
Author keywords
Indexed keywords
DWT,Pyramidal algorithm,VLSI architecture,Word-length effects