A VLSI architecture for watermarking of grayscale images using weighted median prediction Watermarking the digital data is a familiar technique to authenticate and resolve the copyright issues of multimedia data. This paper proposes a new VLSI architecture for watermarking grayscale images using weighted median prediction operation, as this mechanism will have a minimum computation complexity. In this VLSI based data hiding process the secret digital signature is hidden in the host image and analyzed with the PSNR value and Payload capacity.