基于SVD的DCT域和DWT域的经典水印算法，该算法通过提取水印水印的主成分并把该主成分嵌入到奇异值矩阵，鲁邦性非常高。-the principal components of the watermark are embedded into the host image in discrete cosine transform (DCT)　and for the second method, those are embedded into the host image in discrete wavelets transform (DWT). To improve the robustness, the particle swarm optimization (PSO) is used for finding the suitable scaling factors.