提出了一种结合了归一化技术和全息技术的数字水印技术。 首先,利用归一化技术对图像作归一化运算,同时利用全息技术将水印二值图处理为全息图;其次,取归一化后图像分块离散余弦变换的中频系数,对中频系数所组成的矩阵作离散小波变换;最后将全息图嵌入到离散小波变换的低频分量中。 由于图像归一化技术具有抗仿射变换的性能,同时全息技术具有很强的抗裁切的性能,所以此数字水印技术具有很强的抗仿射变换的性能,可以广泛的用于数字作品的版权保护。

A digital watermark technology combining with image normalization and holography was presented. The image was normalized using normalization technology and the binary watermark was processed to get the holographic image based on holographic technology; the middle-frequency coefficients in discrete cosine transform (DCT) domain of every image block were collected and discrete wavelet transform was carried out on the matrix of the middle-frequency coefficients; the holographic image was embedded into the low-frequency coefficients. Because of the anti-affine transformation performance of image normalization and the anti-crop performance of holographic technology, the presented digital watermark technology has a strong performance of anti-affine transformation. The technology can be used to protect the copyright of digital images.