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Watermarking is a potential method for the protection of ownership rights on digital images. A robust, invisible, non-blind watermarking scheme in the wavelet domain is proposed in this paper. The watermark is embedded in the mid frequency band after performing a single level wavelet decomposition using Discrete Wavelet Transform (DWT). The coefficients are grouped randomly prior to watermarking. The watermarked image is tested for various attacks including filtering and geometric attacks. The novelty of the proposed approach is that it provides better resistance to collusion attack also when compared with existing spatial domain approach. The appropriate mid frequency band for embedding the watermark is tested and the HL band proves to be the best. [ABSTRACT FROM AUTHOR]

Digital watermarks have been embedded invisibly in digital media to protect copyrights of legal owners. In this paper two new robust digital color image watermarking schemes using fan beam projections are proposed and their imperceptibility, capacity and robustness are analyzed. The approach FBWLC adds a binary watermark to both the luminance and chrominance content of a color image whereas FBWC adds the watermark to the chrominance content of the color image and is based on Fan Beam Transform that takes multiple projections of the image from different angles. It is observed that FBWC scheme is robust to almost all the attacks and FBWLC scheme is more robust and guarantees zero bit error rate (BER) to most of the attacks on color images namely compression, filtering, blurring and sharpening and is compared with an existing approach based on Spatio Chromatic Discrete Fourier Transform (SCDFT). Also, when compared with other works in color image watermarking, these approaches embed a huge amount of data thereby increasing the watermarking capacity while preserving image quality by subjective evaluation. [ABSTRACT FROM AUTHOR]