以YCgCr和YCbCr颜色空间为基础，分别建立了平行四边形模型和椭圆模型，采用光照补偿法对图像进行预处理，从而避免了光照不均对检测结果所造成的误差。-Based on the YCgCr and YCbCr color spaces, the parallelogram model and the ellipse model are established respectively. The image is pretreated by the light compensation metho