| Abstract: | This paper represents secure watermarking scheme for color images, providing robustness against a set of attacks. Firstly, the image is transformed using an appropriate color transformation. Next each of color channels is transformed through Discrete Wavelet Transform (DWT) and then the Discrete Hadamard Transform (DHT) is applied. By this cascaded transformation, we are in a position to select the most appropriate coefficients, which are close to the low and middle frequencies and uncorrelated in nature. Higher level of security is achieved by introducing encryption among the selected transformed coefficients using a private encryption key. Secondly, we propose non-blind detection scheme. Original image is mandatory, which is based on other widely known watermark detection techniques, but has some modifications. The results are two-stages, multi-resolution watermark decoder that allows efficient identification of the embedded watermarking key without prior notice. The scheme is tested against a variety of legitimate and illicit image processing operations including compression, uniform and Gaussian noise addition, median filtering, cropping and Stir Mark Benchmark. The results presented in this paper are quite convincing and truly demonstrate the robustness of our watermarking method to fundamental image processing operations
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