Research of the image restoration algorithm based on boundary pre-processing in the space domain and fast computing in the frequency domain

On a high power solid laser facility, the wavefront coding (WFC) technology has been adopted to obtain 3m-13m over-long depth of field in an array optical components defect detection system([1]); The lack of the boundary information due to the sudden boundary truncation will cause the ringing effect in the image restoration process. By using the theory of the boundary conditions (BCs), an image enlarged by the different boundary hypothesis can be given; The frequency filtering has been used to find the restored result. The frequency property of the enlarged image and the effect to the boundary of the restored image are analyzed. Effectiveness and speediness of the proposed method are demonstrated by experiment results, which can give excellent deconvolution and noise suppression restored image and reduce the boundary ringing effect under the reflective boundary conditions in a wave-front coding (WFC) system. The experiment shows the proposed algorithm can give satisfactory restoration results on the long depth of field array optical components defect detection system([1]).