crop.py

# Copyright (c) 2021 Alexander E. Siemenn, Iddo Drori, Matthew J. Beveridge
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import cv2 # pip install opencv-python          # https://pypi.org/project/opencv-python/
from scipy import ndimage

def read_rotate_crop(img_path, rotate_crop_params):
    '''
    Rotates and crops the given image.

    Inputs:
    img                  := image path
    rotate_crop_params   := dictionary of values: {theta, x1, x2, y1, y2}, where
        theta            := angle of counter clockwise rotation
        x1               := start pixel of x-axis crop
        x2               := end pixel of x-axis crop
        y1               := start pixel of y-axis crop
        y2               := end pixel of y-axis crop

    Ouputs:
    img                  := rotated and cropped image
    '''
    img = cv2.imread(img_path, cv2.IMREAD_UNCHANGED)  # read images
    rotated = ndimage.rotate(img, rotate_crop_params['theta'])  # reads image and rotates
    img = rotated[rotate_crop_params['y1']:rotate_crop_params['y2'],
          rotate_crop_params['x1']:rotate_crop_params['x2']]  # crops image
    return img