font                   = cv2.FONT_HERSHEY_SIMPLEX
bottomLeftCornerOfText = (10,500)
fontScale              = 1
fontColor              = (255,255,255)
lineType               = 2

cv2.putText(img,'Hello World!', 
    bottomLeftCornerOfText, 
    font, 
    fontScale,
    fontColor,
    lineType)