A Novel Digital Image Watermarking Approach Based on Image Blocks Similarity

In this paper, we propose a simple digital image watermarking algorithm, which can embed the watermark image blocks into the host image based on their blocks similarity coefficient. In the proposed scheme, both of watermark image and host image are divided into image blocks of size 8-by-8, and similarity coefficients between watermark image blocks and host image blocks are computed. Each watermark image block is embedded into the host image location with best similarity, namely, with the largest block similarity coefficient. Since the embedded watermark image blocks and their corresponding host image blocks are similar to some extent, the whole embedded watermark image is well imperceptible. Experimental results show that watermark images embedded by this technique are robust against various attacks, such as noising, cropping, JPEG compression.