一种多重变换域大容量水印方案研究

High-capacity watermarking scheme based on multiple transform domain

提出了多重离散Chirp-Fourier变换(M-DCFT)域水印方案。把多个Chirp类水印信息分别嵌入在不同重数的DCFT域,利用DCFT域Chirp信号的聚集性进行盲检测。以PSNR作为水印容量衡量指标,推导了多重DCFT域的水印容量公式。仿真结果表明,在相同的PSNR限制下,变换域水印容量随变换重数的增大而增加,且远大于空域水印容量。提出的水印方案可以选择把水印嵌入在不同重数的DCFT域,不仅嵌入方式灵活,而且具有更高的水印安全性。

A high-capacity watermarking scheme based on Multiple Discrete Chirp-Fourier Transform （M-DCFT） is proposed, which embeds the watermarks in different M-DCFT domain, and performs the watermark blind detection by the energy peak of its DCFT. The general capacity of the proposed scheme also is derived by PSNR. Experimental results show that the capacity of the proposed watermarking algorithm turns bigger with transform tuple increasing; moreover, the proposed scheme may embed several watermarks in different M-DCFT domain, so the embedding method is more flexible and the watermark security is higher.