RECURSIVE ALGEBRAIC CURVE-FITTING AND RENDERING

We describe a recursive algorithm that uses quadratic algebraic curve segments to vectorize digital images. The closeness of fitting and the smoothness of connection between curve segments are ensured by a recu rsive algebraic curve fitting and a subsequent fine-tuning procedure. The idea is to provide an alternative way to vectorize outside paramet ric schemes, while maintaining the precision of parametric vectorizati on. We can also have all the new features of algebraic representation; for instance, the implicit forms and unique insights into curve shape s and control point weights. We also present a triangular quadtree ren dering scheme for displaying algebraic curves. These algorithms combin e features from both parametric and algebraic schemes to meet differen t requirements for curve fitting.