ABSTRACT
A novel method is proposed for visible watermarking of digital image in frequency domain. The method is based on DCT
modification of original image with respect to watermark image. The host image pixels are transformed into frequency
coefficients as well as the watermark image pixels are also transformed into frequency coefficients using DCT. The
compound mapping function is used to adjust the pixel values close to those of desired visible watermarks. Thus the
watermarking is done in frequency domain using compound mapping function. One who has the watermark image and
mapping function parameters only can remove the watermark. Thus it enhances the security. Experimental results
demonstrate the effectiveness of the proposed approach.
Keywords: - Watermarking, Steganography, Compound mapping