Firstly, research on robust image watermarking. A digital watermarking scheme based on wavelet transform was proposed. It realizes the watermarking extract without the original image using 64×64×8 bit gray image as the watermark signal. In order to e

基于DCT的数字水印处理技术，本水印处理过程利用图像的缩放技术和调整原始图像的直方图，根据人眼视觉特性,在每个DCT变换块的DC分量上嵌入水印信息，并且在水印信息嵌入之前,对其进行置乱加密,提供双重安全保证，接着通过JPEG压缩攻击对DCT域的鲁棒性进行测试，证明了DCT的抗攻击能力。-DCT-based digital watermarking technique, the watermark processing technology and the use of image scaling