iOS App Store Preview Image Resizer

ios_app_store_preview_image_resizer.py

"""
iOS App Store Preview Image Resizer

This script provides functionality to resize images for iOS app store previews. It offers two modes for resizing:
- "pad": This mode will pad the image with white space to fit the target dimensions without cropping.
- "crop": This mode will crop the image to match the target aspect ratio, then resize it to the exact target dimensions.

Usage:
- Modify the `input_dir` variable to point to the directory containing the images you want to resize.
- The script will create output directories named with the target dimensions and the device name.
- By default, the script resizes images for three iOS devices: iPhone 5.5", iPhone 6.5", and iPad 12.9".
- The resizing mode can be set to either "crop" or "pad" in the `__main__` section.

Dependencies:
- PIL (Pillow)
"""

from pathlib import Path

from PIL import Image


def resize_image_for_ios_preview(input_path: Path, output_path: Path, target_size=(1284, 2778), mode="pad"):
    """
    Resizes an image to the specified target size for iOS app store previews.

    Args:
        input_path (Path): Path to the input image.
        output_path (Path): Path to save the resized image.
        target_size (tuple, optional): Target size for the image. Defaults to (1284, 2778).
        mode (str, optional): Resizing mode. Can be "pad" or "crop". Defaults to "pad".
    """
    # Open the input image
    img = Image.open(input_path)

    # Calculate aspect ratios
    src_ratio = img.width / img.height
    tgt_ratio = target_size[0] / target_size[1]

    if mode == "crop":
        # Calculate the cropping box
        if src_ratio > tgt_ratio:
            new_width = int(img.height * tgt_ratio)
            left = (img.width - new_width) // 2
            img = img.crop((left, 0, left + new_width, img.height))
        else:
            new_height = int(img.width / tgt_ratio)
            top = (img.height - new_height) // 2
            img = img.crop((0, top, img.width, top + new_height))

        # Resize the cropped image to the target dimensions
        img = img.resize(target_size, Image.LANCZOS)
    elif mode == "pad":
        # Continue with padding logic as before
        blank_image = Image.new("RGB", target_size, "white")
        img = img.resize((target_size[0], int(img.height * (target_size[0] / img.width))), Image.LANCZOS)
        if img.height < target_size[1]:
            img = img.resize((int(img.width * (target_size[1] / img.height)), target_size[1]), Image.LANCZOS)
        img_position = ((target_size[0] - img.width) // 2, (target_size[1] - img.height) // 2)
        blank_image.paste(img, img_position)
        img = blank_image

    # Save the final image
    img.save(output_path)


if __name__ == "__main__":
    input_dir = Path("/Users/glennjocher/Downloads/images")

    names = "iPhone_5.5", "iPhone_6.5", "iPad_12.9"
    sizes = (1242, 2208), (1284, 2778), (2048, 2732)
    for i, size in enumerate(sizes):
        output_dir = Path(f"/Users/glennjocher/Downloads/images{size[0]}x{size[1]}_{names[i]}")
        output_dir.mkdir(parents=True, exist_ok=True)

        for img_file in input_dir.iterdir():
            if img_file.suffix.lower() in [".jpg", ".jpeg", ".png"]:
                output_file = output_dir / img_file.name
                resize_image_for_ios_preview(img_file, output_file, target_size=size, mode="crop")  # mode=crop or pad