摘要
从图像中提取的直线常出现不完整、端点位置不准确等问题,针对这些问题造成的直线匹配难点,本文提出了一种仿射不变的直线描述子.首先将待匹配直线离散为对应点的集合,将直线描述转化为点的描述,避免了直线不完整造成的支撑区域大小不一致的问题;然后结合直线的方向和长度,定义点描述子的主方向和尺度,通过统计离散点集的局部邻域的梯度信息使描述子具有仿射不变性.为了提高直线匹配速度,在进行直线描述之前,本文采用了极线约束精简了待匹配直线集合,再利用最近邻距离比准则对直线精确匹配.实验结果表明本文提出的直线描述子在仿射、亮度、视点、遮挡等变化条件下具有精确的匹配性能.
Line matching is a difficult problem due to reasons such as incomplete lines,inaccurate locations of endpoints,and so on.To deal with these challenges,we proposed an affine invariant line descriptor.An initial candidate match is dispersed to a set of correspondences.As a result,the problem of inconsistent support region size is resolved because we need only construct descriptors of correspondence points instead of lines.In order to make the descriptor affine invariant,the dominant orientation and the scale of the descriptor are created according to the direction and the length of the line,and gradients of the discrete points set in the local neighborhood are calculated.To speed up line matching,epipolar constraint is used before constructing line descriptors,and the number of potential matches is limited.Then,line matching is preceded accurately by the nearest neighbor distance ratio approach.The experimental results show that the proposed descriptor has accurate line matching under the changes of affine,illumination,viewpoint,and partial occlusion.
出处
《电子学报》
EI
CAS
CSCD
北大核心
2015年第12期2505-2512,共8页
Acta Electronica Sinica
基金
国家自然科学基金(No.61263046
No.61462065)
江西省自然科学基金(No.20122BAB201037)
关键词
直线匹配
直线描述子
仿射不变
极线约束
line matching
line descriptor
affine invariant
epipolar constraint
