A New Digital Color Image Watermarking Algorithm with its FPGA and ASIC Implementation

Abstract

In the world full of visual content, digital image authentication has become an important concern. Digital image watermarking can play a key role in this regard. Though several techniques and algorithms exist in literature but color image watermarking techniques with its hardware implementation are few. The objective of this paper is to introduce a new algorithm for watermarking a color cover image using color watermark. The basic technique is to alter the pixel values of the cover image, based on the similarity between cover image and watermark. The amount of alteration can be controlled by a parameter called modulation index, which also decides the quality of cover image as well as that of extracted watermark image. A pseudo-noise code is used for embedding and extraction of the watermark, hence only authorized users having exact pseudo-noise code can extract the watermark. This is an invisible watermarking technique, so it doesn't affect the appearance of the original image significantly. Furthermore, FPGA as well as ASIC based hardware implementation of the aforesaid algorithm is realized. For real-time application hardware realization is more efficient than software implementation. The proposed algorithm and its VLSI implementation have been compared with stat-of-art research work present in literature. Throughput of the proposed algorithm is high and it can also be used for digital video watermarking.