我正在尝试从视频中裁剪图像,但未显示结果。我知道发生TypeError的原因是因为cropcrop_img中没有内容,但是由于我是opencv的初学者,所以我不知道解决方案。下面的代码是我从使用opencv和raspberry pi和webcam的项目复制而来的。现在,我正在尝试在Windows 10上进行测试,因此可能存在一些接口问题。
代码:-
# -*- coding: utf-8 -*-
import numpy as np
import cv2
video_capture = cv2.VideoCapture(-1)
video_capture.set(3,160)
video_capture.set(4,120)
while(True):
# Capture the frames
ret,frame = video_capture.read()
#print("image recieved");
#cv2.imshow('frame',ret)
# Crop the image
crop_img = frame[60:120,0:160]
cv2.imshow("cropped",crop_img)
# Convert to grayscale
gray = cv2.cvtColor(crop_img,cv2.COLOR_BGR2GRAY)
# Gaussian blur
blur = cv2.GaussianBlur(gray,(5,5),0)
cv2.imshow('show',blur)
# Color thresholding
ret,thresh = cv2.threshold(blur,60,255,cv2.THRESH_BINARY_INV)
# Find the contours of the frame
contours,hierarchy = cv2.findContours(thresh.copy(),1,cv2.CHAIN_APPROX_NONE)
# Find the biggest contour (if detected)
if len(contours) > 0:
c = max(contours,key=cv2.contourArea)
M = cv2.moments(c)
cx = int(M['m10']/M['m00'])
cy = int(M['m01']/M['m00'])
cv2.line(crop_img,(cx,0),720),(255,1)
cv2.line(crop_img,(0,cy),(1280,1)
cv2.drawContours(crop_img,contours,-1,1)
if cx >= 120:
print ("Turn Left!")
if cx < 120 and cx > 50:
print ("On Track!")
if cx <= 50:
print ("Turn Right")
else:
print ("I don't see the line")
#Display the resulting frame
cv2.imshow('frame',crop_img)
if cv2.waitKey(1) & 0xFF == ord('q'):
break\
错误:-
runfile('C:/Users/HP/OneDrive/Desktop/Sultan/Veggitech/Transport robot with Voice Control/Code/Test Code/line_follower_opencv.py',wdir='C:/Users/HP/OneDrive/Desktop/Sultan/Veggitech/Transport robot with Voice Control/Code/Test Code')
Traceback (most recent call last):
File "<ipython-input-2-583afe4334df>",line 1,in <module>
runfile('C:/Users/HP/OneDrive/Desktop/Sultan/Veggitech/Transport robot with Voice Control/Code/Test Code/line_follower_opencv.py',wdir='C:/Users/HP/OneDrive/Desktop/Sultan/Veggitech/Transport robot with Voice Control/Code/Test Code')
File "C:\Users\HP\Anaconda3\lib\site-packages\spyder_kernels\customize\spydercustomize.py",line 827,in runfile
execfile(filename,namespace)
File "C:\Users\HP\Anaconda3\lib\site-packages\spyder_kernels\customize\spydercustomize.py",line 110,in execfile
exec(compile(f.read(),filename,'exec'),namespace)
File "C:/Users/HP/OneDrive/Desktop/Sultan/Veggitech/Transport robot with Voice Control/Code/Test Code/line_follower_opencv.py",line 25,in <module>
crop_img = frame[60:120,0:160]
TypeError: 'NoneType' object is not subscriptable