Image Watermarking Based on Dual Tree Complex Wavelet Transform and Pulse Coupled Neural Network

This paper proposes a new method for image watermarking, based on dual tree complex wavelet transform and pulse coupled neural network. The watermark embedding process consists of three stages. First, the watermark was disturbed in terms of some rules, the same level dual tree complex wavelet transform were performed on the watermark and the host image respectively, and the obtained host subimages were divided into small blocks whose size is the same as the one of the obtained corresponding watermark subimages. Second, the pulse coupled neural network was used to fuse the watermark subimages and the host blocks selected by the contrast sensitivity saliency and the embedding ratio. Finally, the inverse dual tree complex wavelet transform was performed to produce the watermarked image. In the process of extracting the watermark, the obtained watermark subimages were weightily averaged to get a better approximation to the original watermark subimage, and the weight was determined by the embedding ratio. Simulation results will demonstrate the effectiveness of our algorithm.