An expanded 2D DCT algorithm based on convolution

Various convolutional approaches to computing the 1D and 2D discrete cosine transform (DCT) are presented. In the 1D case the method of W. Li (see IEEE Trans. Signal Process., vol.39, no.6, p.1305-13, 1991) is introduced, and a more regular structure than that of the Li method is described. Since both methods are complicated to implement with systolic arrays, a proper array structure is proposed. This structure speeds up the multiplication by processing with real numbers instead of complex numbers. The 2D algorithm and structure are obtained by expansion of the 1D algorithm. The resulting structure is faster than the 1D structure and requires fewer processing elements