目的 结合奇异值和小波变换的优点， 针对彩色载体图像进行水印的嵌入和提取， 提高水印的鲁棒性和安全性。方法 根据基于DWT-SVD的数字水印算法， 对彩色载体图像进行RGB到Lab颜色空间的转换， 对L分量作二级离散小波变换， 选择低频子带并对其进行奇异值分解， 同时对原始QR码水印进行奇异值分解。最后根据人眼视觉系统 （HVS） 特性， 选择合适的嵌入强度因子嵌入水印。结果 文中算法对于高斯噪声、 椒盐噪声、 斑纹噪声和泊松噪声、 JPEG压缩、 小角度的旋转攻击、 缩放攻击以及对比度增强有一定的鲁棒性。结论 该算法能够抵抗常见的水印攻击， 满足数字防伪以及版权保护的需要。

Based on the advantages of wavelet transform and singular value decomposition, a new method was put forward for watermark embedding and extraction of color images, in order to improve the robustness and safety of watermark. A novel digital watermark algorithm based on singular value decomposition and wavelet transform method was used for color space conversion of the color host image from RGB to Lab. Two levels wavelet transformation was carried out on the L components of the color host image in the standard color space, and singular value decomposition was carried out on low frequency sub-band and the original quick response code. At last, the watermark was embedded with an appropriate embedding strength coefficient obtained on the basis of human visual system. The experiments showed that the proposed algorithm had strong robustness against Gaussian, salt & pepper, speckle and Poisson noise attacks, JPEG compression attacks, small-angle rotation attacks, compression attacks and contrast enhancement attacks. In conclusion, the watermarking algorithm was able to resist common watermark attacks and could meet the requirements of digital anti-counterfeiting and copyright protection.