视觉系统结合小波域的水印算法

为了提高嵌入水印抵抗JPEG压缩攻击、亮度更改攻击和大幅裁减攻击的能力,结合人类视觉系统与离散小波变换对数字图像水印算法加以改进:将水印信息嵌入载体图像前,先对水印图像进行置乱处理,然后对载体图片采取小波变换,再综合人类视觉系统特性选取调制参数,最后将水印嵌入到载体图像经小波变换后的低频部分。实验表明改进后的算法能有效提高水印信息抵抗恶意攻击的能力,健壮性良好,并能均衡水印的不可见性和鲁棒性。

A watermark algorithm based on visual system and DWT domain

In order to enhance the ability of embedding watermarking resist JPEG compression attack,brightness change attack and significant reductions in the attack,the watermarking algorithm based on human visual system and the combination of DWT domain on digital image is improved.The algorithm embedded the watermark information into vector image,scrambling the watermarking image,taken wavelet transform in the carrier picture,comprehensive characteristic of human visual system,selection of modulation parameters,embedded the watermark into the low frequency part of wavelet transform.The experiments show that the algorithm can effectively improve the watermark information against malicious attack ability,have good robustness,and balanced the invisibility and robustness.