Halftone image watermarking paper
Tuesday 10 February 2009
Weina Jiang, Professor Anthony TS Ho and Dr Helen Treharne have a paper on halftone image watermarking accepted for publication in the Lecture Notes in Computer Science (LNCS) Transactions on Data Hiding and Multimedia Security journal.
Jiang, W., Ho, A.T.S. & Treharne, H. Novel Least Distortion Linear Gain Model for Halftone Image Watermarking Incorporating Perceptual Quality Metrics. LNCS Transactions on Data Hiding and Multimedia Security.
“In this paper, a least distortion approach is proposed for halftone image watermarking. The impacts of distortion and tonality problems in halftoning are analyzed. An iterative linear gain model is developed to optimize perceptual quality of watermarking halftone images with efficient computation complexity O(1). An optimum linear gain for data hiding error diffusion is derived and mapped into a standard linear gain model, with the tonality evaluated using the average power spectral density. As compared with Fu and Au’s data hiding error diffusion method, our experiments show that our proposed linear gain model can achieve an improvement of between 6.5% to 12% using weighted signal-to-noise ratio (WSNR) and an improvement of between 11% to 23% measured by VIF (visual image fidelity).”