Sensor calibration is a necessary and key step before applying photics sensor to measurement. While applying template in calibration

the first task is to detect and locate the template in complex background. At present

manual detection is used widely

whose efficiency is very low. To solve this problem

a new method for template detection and location under complex background is provided in this paper

which consists of two steps

template detection and precise location. The former implements the template detection using image segmentation and Hough transformation

and the later locates the four key corners on template using SUSAN technique. The experiment result shows that the proposed method is simple and reliable and it can be applied in any complex scene.