# -*- coding: utf-8 -*- import cv2#两个回调函数def HoughLinesP(minLineLength): global minLINELENGTH minLINELENGTH = minLineLength + 1 print "minLINELENGTH:",minLineLength + 1 tempIamge = scr.copy() lines = cv2.HoughLinesP( edges, 1, cv2.cv.CV_PI/180, minLINELENGTH, 0 ) for x1,y1,x2,y2 in lines[0]: cv2.line(tempIamge,(x1,y1),(x2,y2),(0,255,0),1) cv2.imshow(window_name,tempIamge)#临时变量minLineLength = 20#全局变量minLINELENGTH = 20max_value = 100window_name = "HoughLines Demo"trackbar_value = "minLineLength"#读入图片，模式为灰度图，创建窗口scr = cv2.imread("G://homework//building.bmp")gray = cv2.cvtColor(scr,cv2.COLOR_BGR2GRAY)img = cv2.GaussianBlur(gray,(3,3),0)edges = cv2.Canny(img, 50, 150, apertureSize = 3)cv2.namedWindow(window_name)#创建滑动条cv2.createTrackbar( trackbar_value, window_name, / minLineLength, max_value, HoughLinesP)#初始化HoughLinesP(20)if cv2.waitKey(0) == 27: cv2.destroyAllWindows() 
