5_transformations.py

import cv2 as cv
import numpy as np

img = cv.imread("Photos/park.jpg")
cv.imshow("Park", img)

# Translation
def translate(img, x, y):
    transMat = np.float32([[1, 0, x], [0, 1, y]])
    dimensions = (img.shape[1], img.shape[0])
    return cv.warpAffine(img, transMat, dimensions)

# -x --> Left
# -y --> Up
# x --> Right
# y --> Down

translated = translate(img, 100, 100)
cv.imshow("Translated", translated)

# Rotation
def rotate(img, angle, rotPoint = None):
    (height, width) = img.shape[:2]

    if rotPoint is None:
        rotPoint = (width // 2, height // 2)

    rotMat = cv.getRotationMatrix2D(rotPoint, angle, 1.0)
    dimensions = (width, height)

    return cv.warpAffine(img, rotMat, dimensions)

rotated = rotate(img, -45)
cv.imshow("Rotated", rotated)
rotated_rotated = rotate(rotated, -45)
cv.imshow("Rotated Rotated", rotated_rotated)
ninety = rotate(img, -90)
cv.imshow("Ninety", ninety)

# Resize
resized = cv.resize(img, (500, 500), interpolation = cv.INTER_CUBIC)
cv.imshow("Resized", resized)

# Flipping
flip = cv.flip(img, 1) # flipCode can be 0, 1, -1
cv.imshow("Flip", flip)

# Cropping
cropped = img[200:400, 300:400]
cv.imshow("Cropped", cropped)

cv.waitKey(0)