Region coding using improved B-spline surface approximation

A new arbitrary region coding algorithm using a B-spline surface is present ed. Pixels in the coded region are regarded as valid image data, and the pa rameters of the B-spline surface are calculated under certain optimisation criteria. Instead of the traditional least squares error (LSE) criterion, a least squares weighted error (LSWE) criterion is used as the approximation criterion. Simulation results show that the LSWE approach is much better f or region coding than the LSE approach.