图像内容特征 meaning in English

visual subspace

4 . studying the basic method of feature - matched
研究了基于图像内容特征匹配的基本方法。
The present and the future of cbir and the key issues are discussed in this thesis , and some methods of extracting image content are analyzed detailedly
本论文论述了目前国内外基于内容图像检索领域的现状和发展趋势，研究了主要的技术方法，并对图像内容特征的提取方法作出了详细的分析和具体实现。
On the base of these conclusions , we present a novel digital signature - a recoverable active digital signature method for digital image : rads , according to the characteristics of multimedia information like digital image and the requirements of digital image authentication . then we show a lot of experimental results and practical examples to prove rads is an effective and practical digital signature way
在这个基础上，再结合数字图像这种多媒体信息本身的特点和数字图像认证的具体要求，提出了一种新的基于数字图像内容特征的数字签名方法? ?数字图像的一种可恢复性主动数字签名方法rads ，并通过大量的实验和实例来证明rads方法的有效性和实用性。