Identification of piecewise linear uniform motion blur

A single image based motion blur identification scheme is proposed for uniform motion blurs that consist of more than one linear motion component. The proposed scheme is composed of three modules that are a motion direction estimator, a motion length estimator and a motion combination selector. In order to identify the motion directions, the proposed scheme is based on a trial restoration by using forward ramp motion blur in horizontal and vertical directions and an analysis of directional information in frequency domain via a Radon transform. Autocorrelation functions of image derivatives in several directions are employed for estimation of the motion lengths. A proper combination of motion vectors is identified based on an analysis of local autocorrelation functions of non-flat component of restoration results. A simulation example is given to demonstrate the performance of the proposed method.