Image coding using weighted cosine transform

摘要

A new orthogonal transform, called weighted cosine transform (WCT), is developed for digital image coding applications. The new transform is characterized. The transform matrix is the weighted version of that in the discrete cosine transform (DCT). Various commonly used criteria based on the one-dimensional and two-dimensional Markov models have shown that the performance of the order-8 and order-16 WCT is better than the DCT and the phase-shift cosine transform (PSCT), which is an improved version of the DCT. A fast computational algorithm for the WCT is also derived, which, however, requires more computational efforts than the DCT.