基于双分量差值扩展的彩色图像可擦除水印*

针对Tian算法中过度利用差值造成含印图像质量下降严重的问题，提出了基于双分量差值扩展的彩色图像可擦除水印算法。该算法将差值扩展量分散到四个灰度值中，含印图像质量明显提高。实验表明，该方法嵌入的水印不可见性好，擦除水印的图像与原始图像完全相同，适合于图像的精确认证和窜改定位。

Erasable watermark algorithm for color images based on double components difference expansion

To avoid the quality decline of watermarked images from excessive modulation to pixel pairs,this paper proposed an erasable watermark algorithm for color images based on double componpents difference expansion.The algorithm dispersed expansion to four pixel's gray,the quality of watermarked images was improved evidently.The experiments show that the algorithm can assure good imperceptibility for watermarked image and the watermark beseem to exact authentication and tamper localization for image,this waterma...