Image Processing Blog

 Opencv Create a Rectangle import cv2 image = cv2.imread( "readimg.jpg" ) start = ( 10 , 10 ) end = ( 330 , 330 ) color = ( 179 , 255 , 15 ) thickness = 3 image = cv2.rectangle(image , start , end , color , thickness)

 Opencv Color Conversion Gray Scale img = cv2.imread( "image.jpg" ) gray = cv2.cvtColor(img , cv2.COLOR_BGR2GRAY)

 Opencv Get Frame Width and Height import cv2 capture = cv2.VideoCapture( 'readvideo.mp4' ) if capture.isOpened(): w = capture.get(cv2.cv.CV_CAP_PROP_FRAME_WIDTH) h = capture.get(cv2.cv.CV_CAP_PROP_FRAME_HEIGHT) w = capture.get( 3 ) h = capture.get( 4 ) f = capture.get(cv2.cv.CV_CAP_PROP_FPS)

How to install Opencv Python using Pip? pip install opencv-python pip install opencv-contrib-python  

How to make  resizable window in opencv python  import cv2 cv2.namedWindow( "o" , cv2.WINDOW_NORMAL) im = cv2.imread( "image.jpg" ) resized = cv2.resize(im , ( 720 , 480 )) cv2.imshow( "output" , resized) cv2.waitKey( 0 )

 Opencv Python Read Video From Camera import cv2 captureImage = cv2.VideoCapture( 0 ) while ( True ): ret , frame = captureImage.read() gray = cv2.cvtColor(frame , cv2.COLOR_BGR2GRAY) cv2.imshow( 'image' , gray) if cv2.waitKey( 1 ) & 0xFF == ord ( 'q' ): break captureImage.release() cv2.destroyAllWindows()

 OpenCV Python Webcam Control import cv2 cap = cv2.VideoCapture( 0 ) if not cap.isOpened(): raise IOError ( "webcam not available" ) while True : ret , f = cap.read() f = cv2.resize(f , None, fx = 0.5 , fy = 0.5 , interpolation =cv2.INTER_AREA) cv2.imshow( 'I' , f) c = cv2.waitKey( 1 ) if c == 27 : break cap.release() cv2.destroyAllWindows()

 OpenCV Read Video and Resize import cv2 width = 360 height = 240 cap = cv2.VideoCapture( "readvideo.mp4" ) while True : success , img = cap.read() img = cv2.resize(img , (width , height)) cv2.imshow( "frame" , img) if cv2.waitKey( 1 ) and 0xFF == ord ( 'q' ): break

How to Read Video İn Opencv Python The following code is used to read video in OpenCV python. The process of reading video in OpenCV is very similar to reading images. The video is a series of images. All frames in a video sequence must be looped over and then rendered one frame at a time. import cv2 capture = cv2.VideoCapture( 'video.mp4' ) while (capture.isOpened()): r , f = capture.read() gray = cv2.cvtColor(f , cv2.COLOR_BGR2GRAY) cv2.imshow( 'video' , gray) if cv2.waitKey( 1 ) & 0xFF == ord ( 'q' ): break capture.release() cv2.destroyAllWindows()

OpenCV Resize Image With Aspect Ratio The OpenCV resize() method, as the name suggests, resizes the image.  import cv2 def resize (i , window_height = 500 ): aspect_ratio = float (i.shape[ 1 ]) / float (i.shape[ 0 ]) window_width = window_height/aspect_ratio i = cv2.resize(i , ( int (window_height) , int (window_width))) return i img = cv2.imread( 'image.jpg' ) img_resized = resize(img , window_height = 640 ) cv2.imshow( "ResizedImage" , img_resized) cv2.waitKey( 0 ) cv2.destroyAllWindows()