Python openCV codes

Python openCV codes

• 1.
  1 | Pa g e ##########Install opencv module######## pip install opencv-python #######To check opencv version#### import cv2 print(cv2.__version__) #######Read & display gray image##### import cv2 img=cv2.imread('india.jpeg',0) #'0' loads grayscale image print(img) #Display pixel values cv2.imshow('image', img) cv2.waitKey() cv2.destroyAllWindows() #######Read & display color image##### import cv2 img=cv2.imread('india.jpeg',1) print(img) cv2.imshow('image', img) cv2.waitKey() cv2.destroyAllWindows() #######Read & display original image##### import cv2 img=cv2.imread('india.jpeg',-1) print(img) cv2.imshow('image', img) cv2.waitKey() cv2.destroyAllWindows() #########Write image##### import cv2 img=cv2.imread('india.jpeg',-1) print(img) cv2.imshow('image', img) cv2.waitKey() cv2.destroyAllWindows() cv2.imwrite('india.png', img)
• 2.
  2 | Pa g e #########Write image with conditional statements######## import cv2 img=cv2.imread('india.jpeg',-1) print(img) cv2.imshow('image', img) k=cv2.waitKey() if k==27: #Press Escape key cv2.destroyAllWindows() elif k==ord('s'): #press 's' character cv2.imwrite('india.png', img) cv2.destroyAllWindows() #####Drawing functions on OpenCV#### import numpy as np import cv2 img=cv2.imread('india.jpeg',1) img=cv2.line(img, (0,0), (255,255), (147, 96, 44), 10) #(147, 96, 44) is RGB color picker, #10 is line #width cv2.imshow('image', img) cv2.waitKey() #####Drawing functions on OpenCV###### import numpy as np import cv2 img=cv2.imread('india.jpeg',1) img=cv2.arrowedLine(img, (0,0), (255,255), (255, 0, 0), 10) # Blue arrow displayed cv2.imshow('image', img) cv2.waitKey() ############Drawing functions on OpenCV####### import numpy as np import cv2 img=cv2.imread('india.jpeg',1) img=cv2.arrowedLine(img, (0,0), (255,255), (0, 255, 0), 10) # Green arrow displayed cv2.imshow('image', img) cv2.waitKey()
• 3.
  3 | Pa g e #######Drawing functions on OpenCV######## x1,y1----------------- | | | | |-----------------------x2,y2 import numpy as np import cv2 img=cv2.imread('india.jpeg',1) img=cv2.rectangle(img, (0,100), (150,100), (0, 255, 0), 10) #(x1=0,y1=100), (x2=150,y2=100) cv2.imshow('image', img) cv2.waitKey() #####Setting camera parameters####### import cv2 cap = cv2.VideoCapture(0) print(cap.get(cv2.CAP_PROP_FRAME_WIDTH)) print(cap.get(cv2.CAP_PROP_FRAME_HEIGHT)) while(cap.isOpened()): ret, frame = cap.read() if ret == True: gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY) cv2.imshow('frame', gray) if cv2.waitKey(1) & 0xFF == ord('q'): break else: break cap.release() cv2.destroyAllWindows()
• 4.
  4 | Pa g e ########## import cv2 cap = cv2.VideoCapture(0) print(cap.get(cv2.CAP_PROP_FRAME_WIDTH)) print(cap.get(cv2.CAP_PROP_FRAME_HEIGHT)) cap.set(3, 1280) #3 is width parameter cap.set(4, 720) #4 is height parameter print(cap.get(3)) print(cap.get(4)) while(cap.isOpened()): ret, frame = cap.read() if ret == True: gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY) cv2.imshow('frame', gray) if cv2.waitKey(1) & 0xFF == ord('q'): #press 'q' to close the window break else: break cap.release() cv2.destroyAllWindows()
• 5.
  5 | Pa g e #########add_text_to_videos###### import cv2 import datetime cap = cv2.VideoCapture(0) print(cap.get(cv2.CAP_PROP_FRAME_WIDTH)) print(cap.get(cv2.CAP_PROP_FRAME_HEIGHT)) #cap.set(3, 3000) #cap.set(4, 3000) #print(cap.get(3)) #print(cap.get(4)) while(cap.isOpened()): ret, frame = cap.read() if ret == True: font = cv2.FONT_HERSHEY_SIMPLEX text = 'Width: '+ str(cap.get(3)) + ' Height:' + str(cap.get(4)) datet = str(datetime.datetime.now()) frame = cv2.putText(frame, text, (10, 50), font, 1, (0, 255, 255), 2, cv2.LINE_AA) #(10,50) is co-ordinates frame = cv2.putText(frame, datet, (10, 100), font, 1, (0, 255, 255), 2, cv2.LINE_AA) cv2.imshow('frame', frame) if cv2.waitKey(1) & 0xFF == ord('q'): break else: break cap.release() cv2.destroyAllWindows()
• 6.
  6 | Pa g e #########mouse_event_opencv_python########## import numpy as np import cv2 #events = [i for i in dir(cv2) if 'EVENT' in i] #print(events) def click_event(event, x, y, flags, param): if event == cv2.EVENT_LBUTTONDOWN: print(x,', ' ,y) font = cv2.FONT_HERSHEY_SIMPLEX strXY = str(x) + ', '+ str(y) cv2.putText(img, strXY, (x, y), font, .5, (255, 255, 0), 2) cv2.imshow('image', img) if event == cv2.EVENT_RBUTTONDOWN: blue = img[y, x, 0] green = img[y, x, 1] red = img[y, x, 2] font = cv2.FONT_HERSHEY_SIMPLEX strBGR = str(blue) + ', '+ str(green)+ ', '+ str(red) cv2.putText(img, strBGR, (x, y), font, .5, (0, 255, 255), 2) cv2.imshow('image', img) #img = np.zeros((512, 512, 3), np.uint8) img = cv2.imread('lena.jpg') cv2.imshow('image', img) cv2.setMouseCallback('image', click_event) cv2.waitKey(0) cv2.destroyAllWindows() ############