文档介绍：车牌图像倾斜角度矫正方法的研究与实现
摘要
车牌矫正是车牌定位和字符分割的一个重要处理过程。经过车牌定位后所获取的车牌图像不可避免地存在某种程度的倾斜。这种倾斜不仅会给下一步字符分割带来困难,最终也将对车牌的识别的正确率造成直接的影响。本设计主要研究了对车牌图像倾斜角度矫正的算法。本文给出了矫正倾角的四种方法:Hough变换法、Radon变换法、线性回归法和两点法,并详细介绍了这四种方法的原理、算法步骤、具体程序实现过程、仿真结果及各自的优缺点。Hough变换和Radon相似,其抗干扰能力比较强,但是运算量大,程序执行慢,Hough变换法和Radon变换法进行倾角检测的最大精度为1度。它们的优点是可以计算有断点的直线的倾角。最小二乘法的优点就是运算量小,但是其抗干扰能力比较差,容易受到噪声的影响。两点法虽然理论简单,但由于采样点比较多而且这些点服从随机分布,计算均值后能有效抑制干扰。
关键字:图像倾斜角度;倾角矫正;图像处理
Research on Correction Method of Plate Image Angle and its Implementation
Abstract
License plate correction is a license plate localization and sung-i1 is an important process. After the license plate location obtained after vehicle images inevitably exists some degree of tilt. This will not only give next tilt difficult character segment, will finally of vehicle license plate recognition accuracy cause immediate impact. This paper mainly studies the Angle correction of vehicle images of the algorithm. This paper gives the correct Angle of four methods: Hough transform method, Radon transformation method, linear regression method and two points, and introduces the principle of the four methods algorithm process, specific procedures, implementation process, the simulation results and their respective advantages and disadvantages. Hough transform and Radon similar, antiinterference ability is stronger, but the big, program execution gate-level Hough transform method and slow, Radon transformation method for the biggest precision Angle detection 1 degree. Their advantage is that it can calculate the linear inclination breakpoint,. The advantages of least-square method is determinately but antiinterference ability is poorer, vulnerable to noise impact. Two points although theory is simple, but because sampling points more and these point to obey random distribution, mean can effectively restrain calculated after interference.
Keywords: image Angle; Angle correction; Image processing
目录
摘要 I
Abstract II
1. 绪论 1
课题背景及目的 1
国内外研究现状 2
应用范