import cv2 as cv

function	interpretation
cv.imread()	open image
cv.imwrite()	save image
img.shape
cv.imshow(window_name, image)
cv.waitKey(0)	waits until a key is pressed
cv.destroyAllWindows()	destroys the window showing image
cv.resize(src, dsize, interpolation)	dsize is tuple, interpolation
cv.blur(src, (kernel_size, kernel_siez))	blur image using average blur
cv.GaussianBlur()	GaussianBlur
cv2.filter2D(img_src,-1,kernel)	filter
cv.putText()
cv2.addWeighted(src1, alpha, src2, beta, gamma)	add two images