The research of the character image pre-processing focuses on the gray-scale image filtering algorithm, the skew detection of image and character segmentation algorithm; 在字符图像预处理方面,重点研究了灰度图像滤波算法、图像的倾斜检测和字符分割算法;
Perspective distortion exists on the car license plate photograph taken in a skew angle, under such situation direct rotation can't effectively rectify the distorted plate image, hence the distortion rectification procedure is required to precisely extract the plate character. 斜向拍摄的车牌图像存在着透视变形,该情况下直接进行车牌旋转不能有效地矫正,必须进行变形矫正才能准确地提取出各个牌照字符。
When we get image from scanner or digital camera, the image is often skew, so skew detection and skew correction of images for text documents and form documents is the first step for optical character recognition and form analysis. 由于在用扫描仪和数字照相机获得表格文档时,倾斜总是难免的,因此表格图像的倾斜探测和矫正是表格图像分析的第一步,也是表格分析及以后各项识别工作准确性的保证。
In the process of OCR image scanning, images are always placed slantwise to some extent. Such skew image may create difficulty to character segmentation and result to lower character recognition accuracy. 在OCR图像扫描输入的过程中,扫描图像经常会出现某种程度的倾斜,这种倾斜会给下一个字符的切割造成困难,影响字符识别的精度。
During document scanning, the skew of input document images is inevitable. But the algorithms for layout analysis and character recognition are very sensitive to page skew. So skew detection and correction is an important step during preprocessing of document analysis. 在文档扫描过程中,输入的文档图像不可避免地会发生倾斜现象,而布局分析及字符识别算法对页面倾斜都十分敏感,因此倾斜检测和校正是文档分析预处理的重要环节。
PH was 8 to 9 in between that basically maintained neutrality skew alkaline character. pH值均在8~9之间,基本上维持了中性偏碱的特点。
Main works in this thesis include: ( 1) After a comprehensive analysis of existing normalization methods, we decide to correct the skew distortions of character image by taking a combination of moment-based normalization method with gravity-geometry center normalization method. 通过对各种整形算法进行分析,同时考虑到实际应用中经常出现的字符图象倾斜现象,确定了基于图象矩的规格化方法和重心中心规格化方法相结合的整形算法。
In this paper, use the direction and length of motion blur algorithm for automatic identification, license plate location algorithm, skew correction and character segmentation algorithm, BP neural network algorithm to solve the problem of motion blur license plate recognition. 本文应用运动模糊方向和长度自动辨识算法、车牌定位算法、倾斜校正与字符分割算法、BP神经网络识别算法等来解决运动模糊车牌识别问题。
For working station mark in AGVS, first skew rectify and second own rectify are proposed to make distorted character closed to natural character. Then the two stage template matching method is employed to recognize the numeral guide character fast and stably. 对于AGVS系统工位号,则提出一次倾斜校正和二次自校正,使失真字符接近正常字符,并利用两级模板匹配方法对字符进行快速稳定识别。