A utility for padding image files.

img_pad.py

"""
A utility for padding image files. 
"""

from PIL import Image, ImageOps, UnidentifiedImageError
import os.path

def find_files(path, file_names=[], extensions=[]):

    def valid_file(file_path):
        
        # if we arent checking file_names or extension it must be valid
        if len(extensions) == 0 and len(file_names) == 0:
            return True

        if len(extensions) > 0:
            ext = os.path.splitext(file_path)
            if ext[-1] in extensions:
                return True

        if len(file_names) > 0:
            if os.path.split(file_path)[1] in file_names:
                return True        
        
        return False

    files_found = []


    if os.path.isdir(path):
        for dir_name, dirs, files in os.walk(path):
            for file_name in files:
                file_path = os.path.join(dir_name, file_name)
                if valid_file(file_path):
                    
                    files_found.append(file_path)

    elif os.path.isfile(path):
        if valid_file(path):
            files_found.append(path)

    return files_found

def img_pad(path, min_width=0, min_height=0, color=None, overwrite=True):
    original_image = Image.open(path)
    
    # does it need padding?
    if original_image.size[0] < min_width or original_image.size[1] < min_height:
        
        if original_image.size[0] > min_width:
            min_width = original_image.size[0]
        if original_image.size[1] > min_height:
            min_height = original_image.size[1]

        padded_image = ImageOps.pad(original_image, (min_width, min_height), color=color)

        if overwrite:
            new_file_path = path
        else:
            new_file_path = os.path.splitext(path)[0] + "-padded" + os.path.splitext(path)[1]

        padded_image.save(new_file_path)

        return new_file_path

# SETUP

# The path of the files
PATH = r"C:\Users\Martin OHanlon\Documents\raspberrypilearning\fl-blocks-to-text"

# The types of image file to pad as a list e.g. [".png", ".jpg"]
IMAGE_FILES = [".png"]

# Overwrite the files, or create a new file named [filename]-padded.ext
OVERWRITE = True

# The color to pad with as a RBG tuple e.g. (255,255,255), None for transparent
COLOR = None

# Minimum width and height of the images
MIN_WIDTH = 648
MIN_HEIGHT = 0

print("Padding files at {}".format(PATH))
files_to_pad = find_files(PATH, extensions=IMAGE_FILES)

for file_to_pad in files_to_pad:
    try:
        padded_file_path = img_pad(file_to_pad, min_width=MIN_WIDTH, min_height=MIN_HEIGHT, color=COLOR, overwrite=OVERWRITE)
        if padded_file_path is not None:        
            print(" - padded file {}".format(padded_file_path))

    except UnidentifiedImageError as e:
        print("Error - could not pad image - {}\n".format(e))

print("Finished")