System of Measuring the Sub-Pixel Edge of Linear CCD Based on Multi-Scale Transform

Abstract

In order to improve the precision, speed, integration and reliability of the linear CCD system, a multi-scale compress derivation edge detection method of one-dimension image based on wavelet multi-scale transform is presented in this paper. The inspecting system of defects in based on CCD obtains signals of defects in with irradiation of parallel light by using linear array CCD control circuit. The defect signals were collected and transferred by using virtual oscillograph DSO-2902, and the defect signals were analyzed and processed by using computer. Based on it, Before the CCD signal entered the edge detecting system, it had been filtered by filter. Utilizing the characteristic that the grads of grey scale breaks at the edge of picture, the pixel edge of picture was detected by the algorithm which can be used to detect the edge of picture automatically. multi-scale transform used to detect the sub-pixel edge of picture. This method which is more accurate than former single threshold level comparison method can enhance edge and remove noise effectively.