摘要
在方向可变的手绘图形识别中,要使用对方向敏感的特征及识别方法,识别图形的方向是一个前提和关键性的问题。提出了一种基于切向直方图TDH特征的手绘图形方向识别方法,利用图形采样点集的局部切方向统计特征TDH描述手绘图形的笔画方向信息,通过TDH旋转匹配确定待识别图形的方向相对于模板图形方向的旋转角度,进而可将二者旋转对齐。在包含7类共52种点军标的手绘图形集上的实验结果表明,基于TDH的方法对超过80%的图形所得的方向识别角度误差在5°以内,识别速度满足交互实时性的要求,验证了本文方法的有效性。
In order to apply rotation sensitive features and recognition methods for recognizing rotatable sketched symbols,it is essential to recognize its orientation.A TDH-based orientation recognition method is proposed for sketched symbols.Tangent directions of resample points are extracted,and a histogram feature is constructed to carry directional information of the symbol＇s strokes.The rotation angle between an unknown input symbol and a template symbol can be estimated by matching their TDH rotationally,and the input symbol can be adjusted to align with the template one subsequently.With an experiment on a set of 52 sketched course-of-action symbols,the results show that the error of rotation angle recognized by our method is less than 5° for over 80％ of the tested symbols,and the recognition speed meets the real time requirements.
出处
《计算机工程与科学》
CSCD
北大核心
2013年第12期141-145,共5页
Computer Engineering & Science
基金
国家自然科学基金资助项目(61103081)
关键词
手绘图形
方向识别
切向直方图
sketched symbols
orientation recognition
tangent direction histogram（TDH）
