Simultaneous Calculation of DFT and IDFT of Real Two-Dimensional Sequences and Its Application in Digital Image Watermark

This paper firstly discusses some properties of two-dimensional discrete Fourier transform (DFT), and then by exploiting a single two-dimensional DFT, several new direct formulas of simultaneous calculation of the DFT of a real two-dimensional sequence and the inverse DFT (IDFT) of the DFT-transformed real two-dimensional sequence are proposed. Furthermore, this paper applied the new formulas to digital image watermark embedding algorithm, and got a very good experimental result.