Research of image alignment method for PCB
Guo Shi-gang · Journal of Computer Applications · 2009
To detect the quality of Printed Circuit Board (PCB) by template matching needs accurate alignment of the standard image and the detected image. When the location mark is a circle, Hough transform can be used effectively to get the situation of the center, byt has defects in memory occupation and calculation. The image alignment was composed of fuzzy alignment with the prior knowledge of the circle and accurate alignment with circle location parameters given by fuzzy alignment. This method makes the edge extraction and Hough tranform simple and easy to realize, decreases the occupied memory and increased the processing speed.