Comparative performance of various trigonometric unitary transforms for transform image coding

The feasibility of discrete sine transform (DST) and discrete sine cosine transform (DSCT) for digital image processing problems are investigated. Discrete sine transform and discrete cosine transform can be computed by using two FFT’s of original data sequence of length N. Discrete sine cosine coefficients are computed by FFT of data sequence of length N while the inverse is obtained by computing two FFT's. The performance of each of the unitary transforms in the trigonometric family is studied in terms of quantitative performance measures such as variance distribution, rate distortion, Wiener filtering and how well a transform decorrelates the data efficiently for possible bandwidth compression of a signal represented by a firstorder Markov process model. Computer simulation results on a monochrome image are presented.