Two-dimensional Freehand Shapes Recognition Method Research And Application

In the modern information society, computer technology has been involved in various fields of our lives. The Internet has also become popular increasingly, and we depend on computers to get information more than ever before .With computer software and hardware performance which continues to improve and the development of computer graphics, pattern recognition, and human-computer interaction technology, Hand-sketched graphics on-line recognition is one of the research focuses for both national and foreign researchers in this years. The tools of hand-sketched graphics recognition provide designer with the environment in which designers use head-storms to display their designable works.On-line recognition is a branch of pattern recognition and computer vision, and plays a very important role in Intelligence sketch technology. It studies the methods and techniques to recognize a sketch as it its drawn using a digitizer or an instrumented stylus.This paper proposes a identification method of two-dimensional Freehand shapes: Freehand shapes acquired from a 2D input device are represented in discrete coordinates. These data make more sense when they are represented in some mathematical forms, for which Spline is a due candidate.This paper parameterizes the original freehand shape data first, and then fit them using Spline. However, we have found that whole shape Spline fitting smoothes corner points toward circles, diminishing corners which are significant shape features. To remedy this drawback, we calculate curvature along this first pass Spline, search for the local maximums which represent corners, divide the shape data into segments by these corners, and finally fit each segment with Spline. Experimental results show that the proposed approach well retains shape corners and while smoothes segments between these corners.