基于DMWT和QIMM 的图像水印算法

利用多尺度分析的思想，对原始图像进行重复行信号预滤波，把标量小波变换扩展到多小波变换后选取变换出来的低频子带进行水印嵌入。为了保证水印信息的安全性，对水印进行加密置乱处理。然后结合量化索引模数调制（QIMM）的优越性能，根据水印的信息不同选择不同的子块进行嵌入并实现了水印的盲提取。实验证明，算法具有良好的视觉性和鲁棒性，并大大扩展了水印的容量。

Watermarking Algorithm Based on Discrete Multiwavelets Transform and Quantization Index Modulus Modulation

This paper used the idea of multiscale analysis to perform pre-filtering operation on the image with Repeated Rows. It turned the scalar wavelet into discrete multiwavelets transform and then selected the the low frequency subband. For the security of the watermark, the watermark logo is scrambled with a secret key. With the good performance of Quantization Index Modulus Modulation(QIMM), it embedded the watermark bit to different sub-bands and realized blind watermark extraction. Experiments showed that the algorithm in this paper had good image quality and robustness. It also increased the embedding capacity.