Computationally Efficient, Robust Watermarking Using Fast Walsh Hadamard Transform

Abstract

Nowadays, anonymous manipulation of digital data with malicious intention is increasing at an enormous rate. With the advent of various technologies, multimedia signal can easily be downloaded, copied and manipulated at any point of time without much effort. Watermark is the pattern of bits added to the multimedia signals, such as audio, video or images, such that this can be extracted and used to check the authenticity of the received signal. The field of watermarking is growing at a fast pace. Watermarking techniques can be used for a variety of applications such as authentication, video indexing, copyright protection and access control. In this paper, CDMA based robust watermarking algorithm using Discrete Cosine Transform is modified for more robust and computationally efficient applications using Walsh Hadamard Transform. Performed a detailed simulation of both the techniques and compared the results. Compared to the existing technique the proposed technique is proved to be more resistant to attacks, computationally and cost wise more efficient. The new technique results in a good quality extracted watermark even at a low embedding gain even though the information hiding capacity is comparatively less.