The Rounded Hartley Transform

R. J. de Sobral Cintra, H. M. de Oliveira, C. O. Cintra

DOI: 10.14209/its.2002.454

Evento: 2002 International Telecommunications Symposium (ITS2002)

Keywords:

Abstract

"A new multiplication-free transformation derived from DHT is introduced: the RHT. Investigations on the properties of the RHT led us to the identification of an approximate inverse. We showed that RHT is not involutional like the DHT, but it exhibits approximate involutional property. Thus instead of using the actual inverse transform, the RHT is taken as an involutional transformation, allowing the use of direct (multiplicationfree) to evaluate the inverse. A fast algorithm to compute RHT is presented, which offers zero multiplications and O(n log n) additions for power-of-2 blocklengths. This algorithm shows embedding properties. We also extended RHT to the two-dimensional case. This permitted us to perform a preliminary analysis on the effects of RHT on images. Despite of some SNR loss, RHT can be interesting for applications which involve image monitoring associated to decision making, such as military applications or medical imaging."

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