摘要：The rapid growth of the Internet over the last two decades has enormously increased the abundant of computer data such as audio, images and videos to the public. It has greatly facilitated the hacking and unauthorized distribution of those digital media, which become simple and easier due to the adequate technology processing platforms. To enforce the intellectual property rights and digital media from tampering, digital watermarking technique can be used. The pixel values of the watermark which is embedded with the asset image are directly modified in spatial domain watermarking technique. Transform domain watermarking embed the watermark in the transform domain like modifying the spectral coefficients of both asset and watermark images. In this paper, we implement watermarking in hybrid domain which modify the image regarding both spatial and spectral coefficients. DWT is applied to both the asset and message which is to be hidden in the asset image. The watermark is embedded spatially with the HL, LH and HH components which has been wavelet transformed using various wavelet filters. The Mean Square Error (MSE) and Peak Signal-to-Noise Ratio (PSNR) are evaluated to test the imperceptibility of the watermark. Watermarked image suffers some different signal attacks like compression, adding salt and pepper noise, image cropping, image rotation and filter which are used to evaluate the robustness of a watermark. Simulation results show the Daubechies 10 wavelet produces better response among all the others, at the cost of more computation.
