//求一直线与图边界的交点
bool get_cross_pt_with_pic(CvPoint input_pt1,CvPoint input_pt2,vector<CvPoint>& cross_pt,IplImage* img)bool get_cross_pt_with_pic(CvPoint
//求一直线与图边界的交点
bool get_cross_pt_with_pic(CvPoint input_pt1,CvPoint input_pt2,vector<CvPoint>& cross_pt,IplImage* img)bool get_cross_pt_with_pic(CvPoint