Abstract: This paper presents a novel method for interpreting online multi-stroke sketching with straight lines. The multi-strokes are interpreted as sketch content and are used to generate 2D geometric primitives. The pretreatment approach proposed is able to interpret the dashed or continuous strokes. Through between two strokes fitting line position relations, it is proposed to estimate which is the multi-stroke sketching, and gives the multi-stroke fitting line method using itself characteristic. The distinguish method is proposed for start or terminal points of the multi-stroke sketching. The integrated definitions of straight line are given. This paper develops a human-computer interface prototype system FSR using the proposed theory, which makes system interface easy and friendly to user. The FRS system has been tested with a number of multi-stroke sketches, and the test results show that the algorithm achieves a satisfactory interpretative efficiency.

Key words: online, multi-stroke sketching, interpretation, straight line, time-space relationship

摘要： 综合考虑笔划的时空关系对在线多笔划手绘直线段进行识别。基于时间关系进行多笔划预处理；详细讨论基于空间关系的多笔划绘制直线段的识别方法。提出利用两条笔划拟合直线段间的位置关系进行多笔划判定的方法；提出依据其原有拟合特征的多笔划直线段拟合方法及相应的首尾点确定方法；并给出带线型直线段的完整定义。通过算例对提出的算法加以验证和应用。

关键词: 在线, 多笔划草图, 识别, 直线段, 时空关系