US Patent 7418136 Method of shape recognition using postulated lines

A method for recognizing shapes is disclosed. A computer, such as a handheld computer with pen input, is used to receive a drawing from a user. The user's drawing is then analyzed to identify the location of potential vertices of angles or knots of splines using a technique of hypothesizing lines between known important points and calculating the distance between other points and that Postulated line. This process is repeated until all important points are located. Also disclosed is a method for determining whether a set of points is straight or curved.