摘要
提出了两种基于圆形的单幅图像平面几何量测方法。第一种算法首先计算出与待测对象平行的直径,然后获得圆形所在平面上任意两点之间的距离。受待测线段位置、方向等影响,量测结果的精度各向差异大。第二种算法首先求取圆形的外接正方形,将问题转化为包含正方形的平面距离量测。模拟图像与真实图像的测试结果表明,第二种算法的量测精度更具有稳定性。
Measuring distance from images is a common task in engineering task and our daily lives.Distance measurement based on single image which only employs the clues in the image has become a new popular technique.Since circles are common in daily life and process good geometric properties,they has been one of the most important clues for single image measurement.We propose two methods of measuring distance using circles in one single image.Both of them need to compute the projected center of circle and vanishing line of the plane firstly.Then we compute the diameter with the first method,which is parallel to the unknown line segment.After that we can obtain the distance between any two points on the plane based on cross ratio.Under the influence of the location and direction of the line segment to be measured,the errors of the results are obvious diverse in different directions.Instead of diameter the second one compute the exterior of circle.Then the core process of the algorithm is transformed to the distance measurement based on square.Tests on synthetic and real images show that the quality of the second one is better.
出处
《武汉大学学报(信息科学版)》
EI
CSCD
北大核心
2012年第3期348-353,共6页
Geomatics and Information Science of Wuhan University
基金
国家科技支撑计划资助项目(2012BAH35B02)
江苏省高校自然科学重大基础研究资助项目(10KJA420025)
关键词
圆形
灭线
虚圆点
交比
单幅图像
距离量测
circles
vanishing line
circular points
cross ratio
single image
distance measurement