Increased Robustness and Security of Digital Watermarking Using DS-CDMA

Digital Watermarking is a popular method for discouraging illicit copying of multimedia data. In this paper a blind, robust and secure watermarking technique based on DS-CDMA is presented. By using this technique a watermark can be extracted at very high PSNR value with very low BER. An adaptive approach is used to select the coefficients in the DCT domain, where the watermark is to hide. This significantly reduces BER. Multiple spreading codes can be used to make this scheme secure and more robust against JPEG compression, scaling and cropping.