一種基於YCbCr色彩空間之彩色影像浮水印演算法

Abstract

本論文提出一種基於YCbCr色彩空間之彩色數位浮水印影像演算法，目的在有效防止浮水印遭受各種攻擊的破壞，並保持浮水印的透明度。為了加強浮水印的強韌度，本研究整合了離散小波轉換、離散餘弦轉換以及雜訊可見函式等技術；同時為了增加浮水印的透明度，將浮水印嵌入中高頻位置，使得浮水印在客觀的數據或主觀的判定上皆有良好的效果。本演算法所加密的浮水印經過壓縮、模糊、銳化、亮度等攻擊，皆仍具有良好的透明度與強韌度，使彩色數位影像的智慧財產權得到更多的保護。

In this paper, we proposed an algorithm to improve the robustness and transparency for color image watermarking with YCbCr color space. In order to improve the robustness, we integrate Discrete Wavelet Transform (DWT), Discrete Cosine Transform (DCT) and Noise Visibility Function (NVF). Besides, the transparency of watermark was improved by embedding the watermark in the mid-high frequency range. Several watermarked color images with the proposed algorithm were tested against the attacks of compression, blur, sharpen and brightness. The experimental results show that the proposed algorithm of encryption for color image watermark is available for protecting the intellectual property of color image.