An improved scaling factor for robust digital image watermarking scheme using DWT and SVD

Abstract

As the internet has becoming very popular for digital media sharing, the digital media is easy to be accessed, downloaded and vulnerable to image processing attacks. Digital watermarking is a technique used to secure information by embedding an additional information known as watermark into the original data. The proposed scheme is approach to improve scale factor for robust image watermarking using two level of Discrete Wavelet Transform with Singular Value Decomposition. The first and second level of DWT decomposition are performed on HL and HL1 sub band respectively. One of the main contribution of this proposed approach is the decomposition of host image using two level DWT decomposition. The aim of this project primarily is to enhance the robustness of watermarking techniques by obtaining the most optimize scaling factor which increased and control the strength of watermarked image. Scale factor is a coefficient that can influence the quality and robustness of watermarked image. To achieve the research objectives, three phases of research framework are fulfilled; First phase is the analysis on scaling factor, DWT and SVD, secondly is the watermark encoding and the generation of scale factor value and lastly is the evaluation of watermarked image quality and robustness based on the scale factor. The highest PSNR recorded is 69.2112 with best scale factor 0.01. The experimental result shows significant improvement on the quality and robustness of the watermarked image using this proposed scheme.