A gray level image with rich details is used as a watermark and embedded in vector transform domain, more than scalar transform domain used traditionally such as discrete cosine transform domain, etc.

本文提出了一种新的数字静止图像的水印嵌入算法，该算法将含有丰富细节信息的灰度级图像作为水印，水印嵌入过程不是在传统的标量变换域(如离散余弦变换域等)内进行，而是在矢量变换域实现。

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Variable characteristics were captured in discrete cosine transform (DCT) domain of JPEG images and from their decompressed versions with these functions.

这些函数从JPEG图像离散余弦变换(DCT)域及其解压图像所在空域中提取易变特征。

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There are two main transform domain methods, one is to use the discrete cosine transformation (DCT); the other would be the use of discrete wavelet transforms (DWT).

目前主要有两种变换域方法，一种是使用离散余弦变换(DCT)，另一种是使用离散小波变换(DWT)。

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