imutils.py

# Import the necessary packages
import numpy as np
import cv2

# Translation
def translate(image, x, y):
	# define the translation matrix and perform the translation
	M = np.float32([[1, 0, x], [0, 1, y]])
	shifted = cv2.warpAffine(image, M, (image.shape[1], image.shape[0]))
	# return the translated image
	return shifted

# Rotation
def rotate(image, angle, center=None, scale=1.0):
	# grab the dimensions of the image
	(h, w) = image.shape[:2]
	# if the center is None, initialize it as the center of
	# the image
	if center is None:
		center = (w / 2, h / 2)
	# perform the rotation
	M = cv2.getRotationMatrix2D(center, angle, scale)
	rotated = cv2.warpAffine(image, M, (w, h))
	# return the rotated image
	return rotated

# Resize
def resize(image, width=None, height=None, inter=cv2.INTER_AREA):
	# initialize the dimensions of the image to be resized and
	# grab the image size
	dim = None
	(h, w) = image.shape[:2]
	# if both the width and height are None, then return the
	# original image
	if width is None and height is None:
		return image
	# check to see if the width is None
	if width is None:
		# calculate the ratio of the height and construct the
		# dimensions
		r = height / float(h)
		dim = (int(w * r), height)
	# otherwise, the height is None
	else:
		# calculate the ratio of the width and construct the
		# dimensions
		r = width / float(w)
		dim = (width, int(h * r))
	# resize the image
	resized = cv2.resize(image, dim, interpolation=inter)
	# return the resized image
	return resized