Improved reversible visible image watermarking based on HVS and ROI-selection

Reversible visible watermarking is used to combat the copyright infringement which can perfectly restore the original cover image by removing the embedded visible watermark. This paper proposes an improved reversible visible image watermarking scheme based on human visual system (HVS) and a region of interest selection (ROI-selection) strategy. Firstly, the cover image is partitioned into non-overlapped blocks. Then, a visual effect factor (VEF) based on HVS is adopted to adaptively modify the pixel values, which can provide a better fusion effect for the visible watermark and the cover image. The VEF value is determined by using the estimated watermarked and non-watermarked blocks within the neighborhood of each block. Finally, the visible watermark is embedded into the divided blocks using the traditional difference-expansion method, and a ROI-selection strategy is designed to find the most suitable regions for watermark embedding. Experimental results show the effectiveness and superiority of the proposed scheme compared to some existing works.