<p>Authenticity and integrity of digital media is of primary concern in transmission and reception of multimedia data. We propose a digital image watermarking scheme that depends solely on the secrecy of the security key and not that of the watermarking algorithm. The proposed digital watermarking scheme is based upon Discrete Cosine Transform and uses properties of the transform to achieve the least visible distortion in the watermarked image. The proposed technique involves a unique method for spreading, embedding and extracting the watermark. It allows for five separate levels of security, all of which must be affirmed to. The watermarked images were subjected to image cropping, JPEG lossy compression and other destructive attacks with a minimum level of 65% extraction. The proposed technique also supports implementation using Discrete Wavelet Transforms (DWT). Keywords: Digital Watermarking, quantization, iscrete Cosine Transform, Discrete Wavelet Transform</p>
Dr. Shikha Tripathi, Husami, N., Desai, A. Vamsi, and Satija, A., “New Quantization Based Watermarking Scheme For Digital Images”, International Conference on Systemics, Cybernetics & Informatics (ICSCI-2005), 2005.