A Feature based Semi-Fragile Watermarking Mechanism for Gray-Scale Digital Image Authentication.

As the use of internet increases day by day, the authentication as well as integrity issues are also increased. This paper proposed the semi fragile watermarking algorithm which discriminate the malicious and non-malicious attacks and work accordingly. The algorithm is designed in such a way that the watermark is generated from the original image. The features of the image are extracted using DWT and canny edge detection method. These features’ image is worked as watermark image. To embed this watermark in original image the combination of DWT, DCT and SVD transforms are used. Using the advantages of the hybrid transform, the algorithm can achieve good result. With this algorithm, the imperceptibility which is measured using PSNR is increased as compare to other researchers’ system. To check the robustness of the algorithm, numbers of attacks are applied on watermarked image. The experimental outputs show that the algorithm is robust with JPEG compression, Gaussian Noise, Salt and Pepper, Sharpen Image, Median Filter. For the authentication of the image, the proposed algorithm is preferable.