Jelena Kovacevic and Markus Püschel (Proc. IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP), Vol. 3, 2006)
Sampling Theorem Associated with the Discrete Cosine Transform
Preprint (154 KB)
Published paper (link to publisher)
Bibtex

One way of deriving the discrete Fourier transform (DFT) is by equispaced sampling of periodic signals or signals on a circle. In this paper, we show that an analogous derivation can be used to obtain the DCT (type 2). To achieve this goal, we replace the circle by a line graph with symmetric boundary conditions, and define signal space, filter space, and filtering operation appropriately. Further, we derive the corresponding sampling theorem including the proper notions of “bandlimited” and “sinc function.” The results show that, in a rigorous sense, the DCT is closely related to the DFT, and can be introduced without concepts from statistical signal processing as is the current practice.

Keywords:
Algebraic signal processing theory: Current status, Discrete cosine and sine transforms