crop_thesis_covers.py

import pathlib
import imageio.v3 as iio

target_aspect_ratio = 0.71
imgdir = pathlib.Path("./content/images/theses")
for extension in ['.png', '.jpeg', '.jpg']:
    for imgfile in imgdir.glob(f"*{extension}"):
        # Read image and compute current aspect ratio
        image = iio.imread(imgfile)
        aspect_ratio = image.shape[1] / image.shape[0]
        shape = image.shape

        # Crop image to match target aspect ratio
        if aspect_ratio > target_aspect_ratio:
            new_width = round(target_aspect_ratio * image.shape[0])
            if image.shape[1] - new_width > 1:  # ignore 1 pixel differences
                offset = (image.shape[1] - new_width) // 2
                image = image[:, offset : offset + new_width]
        else:
            new_height = round(image.shape[1] / target_aspect_ratio)
            if image.shape[0] - new_height > 1:
                offset = (image.shape[0] - new_height) // 2
                image = image[offset : offset + new_height, :]

        # If the image size has changed, overwrite image file
        if image.shape != shape:
            print(f"Resized {imgfile.relative_to(imgdir)} from {shape} to {image.shape}")
            iio.imwrite(imgfile, image)