我試圖做一個臉部跟蹤器,將Haar Cascade分類與Lucas Kanade良好的特徵檢測相結合。但是,我不斷收到一個錯誤,我無法弄清楚它的含義以及如何解決它。OpenCV錯誤:(-215)size.width> 0 && size.height> 0在函數imshow中
任何人都可以幫助我嗎?
錯誤:
line 110, in <module>
cv2.imshow('frame',img)
error: /build/buildd/opencv-2.4.8+dfsg1/modules/highgui/src/window.cpp:269:
error: (-215)size.width>0 && size.height>0 in function imshow
代碼:
from matplotlib import pyplot as plt
import numpy as np
import cv2
face_classifier = cv2.CascadeClassifier('haarcascades/haarcascade_frontalface_default.xml')
cap = cv2.VideoCapture(0)
# params for ShiTomasi corner detection
feature_params = dict(maxCorners = 200,
qualityLevel = 0.01,
minDistance = 10,
blockSize = 7)
# Parameters for lucas kanade optical flow
lk_params = dict(winSize = (15,15),
maxLevel = 2,
criteria = (cv2.TERM_CRITERIA_EPS | cv2.TERM_CRITERIA_COUNT, 10, 0.03))
# Create some random colors
color = np.random.randint(0,255,(100,3))
# Take first frame and find corners in it
ret, old_frame = cap.read()
cv2.imshow('Old_Frame', old_frame)
cv2.waitKey(0)
old_gray = cv2.cvtColor(old_frame, cv2.COLOR_BGR2GRAY)
restart = True
#while restart == True:
face = face_classifier.detectMultiScale(old_gray, 1.2, 4)
if len(face) == 0:
print "This is empty"
for (x,y,w,h) in face:
focused_face = old_frame[y: y+h, x: x+w]
cv2.imshow('Old_Frame', old_frame)
face_gray = cv2.cvtColor(old_frame,cv2.COLOR_BGR2GRAY)
gray = cv2.cvtColor(focused_face,cv2.COLOR_BGR2GRAY)
corners_t = cv2.goodFeaturesToTrack(gray, mask = None, **feature_params)
corners = np.int0(corners_t)
print corners
for i in corners:
ix,iy = i.ravel()
cv2.circle(focused_face,(ix,iy),3,255,-1)
cv2.circle(old_frame,(x+ix,y+iy),3,255,-1)
plt.imshow(old_frame),plt.show()
# Create a mask image for drawing purposes
mask = np.zeros_like(old_frame)
while(1):
ret,frame = cap.read()
frame_gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
# calculate optical flow
p1, st, err = cv2.calcOpticalFlowPyrLK(old_gray, frame_gray, corners_t, None, **lk_params)
# Select good points
good_new = p1[st==1]
good_old = corners_t[st==1]
# draw the tracks
print "COLORING TIME!"
for i,(new,old) in enumerate(zip(good_new,good_old)):
print i
print color[i]
a,b = new.ravel()
c,d = old.ravel()
mask = cv2.line(mask, (a,b),(c,d), color[i].tolist(), 2)
frame = cv2.circle(frame,(a, b),5,color[i].tolist(),-1)
if i == 99:
break
img = cv2.add(frame,mask)
cv2.imshow('frame',img)
k = cv2.waitKey(30) & 0xff
if k == 27:
break
# Now update the previous frame and previous points
old_gray = frame_gray.copy()
p0 = good_new.reshape(-1,1,2)
cv2.destroyAllWindows()
cap.release()
這一行:'cv2.imshow( 'Old_Frame',old_frame_resized)'其中old_frame_resized界定? – cziemba
對不起,它實際上是cv2.imshow('Old_Frame',old_frame)。這個錯誤仍然存在,雖然 – user3377126
任何'imshow'的想法是拋出錯誤?錯誤可能意味着圖像是空的。我建議檢查'cap.read()'返回值,特別是False的'ret'值,這意味着捕獲失敗。 – cziemba