期刊文献+
共找到3篇文章
< 1 >
每页显示 20 50 100
基于PCA与不变矩的车标定位与识别 被引量:18
1
作者 王枚 王国宏 +1 位作者 房培玉 孙淑娟 《武汉大学学报(信息科学版)》 EI CSCD 北大核心 2008年第1期36-40,共5页
在车牌位置确定的情况下,利用车标边缘特点在车牌上方一定范围内检测车标。提出车标似真度的概念,将检测到的车标图像映入PCA生成的特征车标空间,得到的重构图像与原图像进行车标真实性检测,减少车标的误定位;然后利用不变矩的旋转、尺... 在车牌位置确定的情况下,利用车标边缘特点在车牌上方一定范围内检测车标。提出车标似真度的概念,将检测到的车标图像映入PCA生成的特征车标空间,得到的重构图像与原图像进行车标真实性检测,减少车标的误定位;然后利用不变矩的旋转、尺度及平移均不变的特性,定义不变矩的最小矩距离进行车标识别。通过实测车标图像的定位和识别实验表明,该方法是有效和可行的。 展开更多
关键词 车标识别 特征车标 似真度 不变 最小矩距离
下载PDF
基于小波变换和不变矩的车标识别方法 被引量:4
2
作者 王枚 王国宏 +1 位作者 高学强 吕建敏 《海军航空工程学院学报》 2007年第6期655-658,共4页
形状特征是目标识别的重要参数,小波变换的低频部分代表物体的总体形状特征,而图像中的噪声主要分布于高频部分.根据这一特征,利用小波变换消除噪声提取目标形状,进而利用特征不变矩距离进行分类,实现目标识别,将该方法应用在实测车标... 形状特征是目标识别的重要参数,小波变换的低频部分代表物体的总体形状特征,而图像中的噪声主要分布于高频部分.根据这一特征,利用小波变换消除噪声提取目标形状,进而利用特征不变矩距离进行分类,实现目标识别,将该方法应用在实测车标图像的识别中,结果表明识别效果较好. 展开更多
关键词 小波变换 不变 最小矩距离 车标识别
下载PDF
Minimum distance constrained nonnegative matrix factorization for hyperspectral data unmixing 被引量:2
3
作者 于钺 SunWeidong 《High Technology Letters》 EI CAS 2012年第4期333-342,共10页
This paper considers a problem of unsupervised spectral unmixing of hyperspectral data. Based on the Linear Mixing Model ( LMM), a new method under the framework of nonnegative matrix fac- torization (NMF) is prop... This paper considers a problem of unsupervised spectral unmixing of hyperspectral data. Based on the Linear Mixing Model ( LMM), a new method under the framework of nonnegative matrix fac- torization (NMF) is proposed, namely minimum distance constrained nonnegative matrix factoriza- tion (MDC-NMF). In this paper, firstly, a new regularization term, called endmember distance (ED) is considered, which is defined as the sum of the squared Euclidean distances from each end- member to their geometric center. Compared with the simplex volume, ED has better optimization properties and is conceptually intuitive. Secondly, a projected gradient (PG) scheme is adopted, and by the virtue of ED, in this scheme the optimal step size along the feasible descent direction can be calculated easily at each iteration. Thirdly, a finite step ( no more than the number of endmem- bers) terminated algorithm is used to project a point on the canonical simplex, by which the abun- dance nonnegative constraint and abundance sum-to-one constraint can be accurately satisfied in a light amount of computation. The experimental results, based on a set of synthetic data and real da- ta, demonstrate that, in the same running time, MDC-NMF outperforms several other similar meth- ods proposed recently. 展开更多
关键词 hyperspectral data nonnegative matrix factorization (NMF) spectral unmixing convex function projected gradient (PG)
下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部