Abstract
Full-frame irreversible compression of highly-correlated images performed using the discrete cosine transform (DCT), because of its excellent energy compaction ability. Since computerized tomography (CT) images have general structures consisting of an approximately elliptical region containing almost all of the image energy and are bounded by a region in which the image intensity is essential zero, the property must be introduced into the source model for performing transform coding analysis. Besides DCT, the discrete Hartley transform (DHT) is a real transform which have been shown to be essentially equivalent to the discrete Fourier transform (DFT) in all aspects and is suitable to be used in transform coding for real signals. In this paper, energy compaction capabilities of DCT and DHT using 2D source model with boundary constraints, both separable and non-separable, are explored. Experiments are performed to verify the results of the paper.