Code funktioniert unter OpenCV Version 3.4.4
<pre>from picamera[[Datei:OpencvOpticalFlowPICam.array import PiRGBArrayfrom picamera import PiCameraimport timeimport numpy as npimport cv2py]]
# initialize the camera and grab a reference to the raw camera capturecamera = PiCamera()camera.resolution = (640, 480)camera.framerate = 32camera.rotation = 0rawCapture = PiRGBArray(camera, size=camera.resolution) # allow the camera to warmuptime.sleep(1) print(cv2.__version__) # params for ShiTomasi corner detectionfeature_params = dict( maxCorners = 100, qualityLevel = 0.3, minDistance = 7, blockSize = 7 ) # Parameters for lucas kanade optical flowlk_params = dict( winSize = (15,15), maxLevel = 2, criteria = (cv2.TERM_CRITERIA_EPS | cv2.TERM_CRITERIA_COUNT, 10, 0.03)) # Create some random colorscolor = np.random.randint(0,255,(100,3)) first_frame = True for frame in camera.capture_continuous(rawCapture, format="bgr", use_video_port=True): image = frame.array #ret, frame = frame frame_gray = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY) if first_frame: # Take first frame and find corners in it old_gray = frame_gray.copy() p0 = cv2.goodFeaturesToTrack(old_gray, mask = None, **feature_params) # Create a mask image for drawing purposes mask = np.zeros_like(old_gray) # print(old_gray) first_frame = False # calculate optical flow p1, st, err = cv2.calcOpticalFlowPyrLK(old_gray, frame_gray, p0, None, **lk_params) # Select good points good_new = p1[st==1] good_old = p0[st==1] # draw the tracks for i,(new,old) in enumerate(zip(good_new,good_old))Datei: a,b = newOpencvOpticalFlowUSBCam.ravel() c,d = old.ravel() mask = cv2.line(mask, (a,b),(c,d), color[ipy].tolist(), 2) frame = cv2.circle(frame_gray,(a,b),5,color[i].tolist(),-1) img = cv2.add(frame_gray,mask) # print(img) cv2.imshow('frame',img) k = cv2.waitKey(30) & 0xff if k == 27: break rawCapture.truncate(0) # Now update the previous frame and previous points old_gray = frame_gray.copy() p0 = good_new.reshape(-1,1,2) cv2.destroyAllWindows()camera.close()</pre>
[[Datei:OpencvWorkshopOpticalFlow.jpg|400px]]