imutils.py

import numpy as np
import cv2

def translate(image, x, y):
  M = np.float32([[1,0,x], [0,1,y]])
  shifted = cv2.warpAffine(image, M, (image.shape[1], image.shape[0]))
  return shifted 

def rotate(image, angle, center = None, scale = 1.0):
  (h, w) = image.shape[:2]
  if center is None:
    center = (w//2, h//2)
  M = cv2.getRotationMatrix2D(center, angle, scale)
  rotated = cv2.warpAffine(image, M, (w, h))
  return rotated

def resize(image, ratio=None, width=None, height = None, inter = cv2.INTER_AREA):
  dim = None
  (h, w) = image.shape[:2]
  if width is None and height is None and ratio is None:
    return image
  elif width is None and ratio is None:
    r = height/float(h)
    dim = (int(w*r), height)
  elif width is None and height is None:
    r = ratio
    dim = (int(w*r), int(h*r))
  else: 
    r = width/float(w)
    dim = (width, int(h*r))
  resized = cv2.resize(image, dim, interpolation=inter) 
  return resized

def flip(image, axis):
  return cv2.flip(image, axis)