基于混沌的自适应图像数字水印算法

基于混沌序列的优良性能,该文提出一种基于混沌序列的DCT域数字水印的改进算法.首先采用混沌模型算法来生成混沌随机序列,然后利用人眼视觉系统（HVS）模型对图像感知的视觉掩蔽效应以及DC分量比任何AC分量都有更大的感觉容量的特性,将原始图像分块分类,最后根据分类的结果,将不同强度的水印分量嵌入到不同图像块的DC分量上,实现了混沌水印在原始宿主图像上的自适应嵌入,从而兼顾了水印的不可见性和鲁棒性.实验结果有效地支持了这个结论,所产生的隐形水印体现了很好的稳健性.

An Adaptive Image Digital Watermarking Algorithm Based On Chaotic Sequence

In this paper an improved algorithm in DCT domain based on chaotic sequence is proposed.Exploiting some characteristics of Human Visual System(HVS) and DC components having much larger perceptual capacity than any AC components, the algorithm splits the original image into blocks and classifies these blocks based on visual masking.Watermark components with different strength are inserted into some DCT coefficients according to the classification,so watermark is adaptive embedded into the DC components of the original image.The experimental results show that the embedded watermark is invisible and robust against noise and commonly used imageprocessing methods such as Gaussian,JPEG.,Median filtering etc.