Recognising and processing technology of on-line freehand concept sketch
手绘草图笔触识别与规整技术研究*

Based on the thinking habits and working situations of industrial designers,this paper prosewted a novel method for preprocessing on-line freehand concept sketches,especially line drawing strokes during the conceptual design stage.Firstly,It estimated the number of corners using the drawing speed and the density of sample points,and then divided strokes in corners.Secondly,fitted the divided strokes with 2D parametric curves based on least-squares.Likewise,in order to solve problem about processing overtracing strokes,least-squares test enable them to tidy a single regular shape.Furthermore,extracted the graph topology of strokes using adaptive threshold.The test result showed that this method was in effect on dealing with complex structure and comprehending the meaning of sketches in the process of product innovation.