如果你正在使用的是OpenCV2.4,那就不太好了:KalmanFilter是无法使用的,因为你无法设置状态转移(或任何其他)矩阵。
对于OpenCV3.0,它会正常工作,像这样:
import cv2, numpy as np
meas=[]
pred=[]
frame = np.zeros((400,400,3), np.uint8)
mp = np.array((2,1), np.float32)
tp = np.zeros((2,1), np.float32)
def onmouse(k,x,y,s,p):
global mp,meas
mp = np.array([[np.float32(x)],[np.float32(y)]])
meas.append((x,y))
def paint():
global frame,meas,pred
for i in range(len(meas)-1): cv2.line(frame,meas[i],meas[i+1],(0,100,0))
for i in range(len(pred)-1): cv2.line(frame,pred[i],pred[i+1],(0,0,200))
def reset():
global meas,pred,frame
meas=[]
pred=[]
frame = np.zeros((400,400,3), np.uint8)
cv2.namedWindow("kalman")
cv2.setMouseCallback("kalman",onmouse);
kalman = cv2.KalmanFilter(4,2)
kalman.measurementMatrix = np.array([[1,0,0,0],[0,1,0,0]],np.float32)
kalman.transitionMatrix = np.array([[1,0,1,0],[0,1,0,1],[0,0,1,0],[0,0,0,1]],np.float32)
kalman.processNoiseCov = np.array([[1,0,0,0],[0,1,0,0],[0,0,1,0],[0,0,0,1]],np.float32) * 0.03
while True:
kalman.correct(mp)
tp = kalman.predict()
pred.append((int(tp[0]),int(tp[1])))
paint()
cv2.imshow("kalman",frame)
k = cv2.waitKey(30) &0xFF
if k == 27: break
if k == 32: reset()