Author: thrasos

Security information should rely on the secret and not the secrecy of the algorithm.

Generating ASCII art from images using Python3 and PIL (Python Image Library)

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pip install Pillow

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from PIL import Image

import os



ASCII_CHARS = [ '#', '?', '%', '.', 'S', '+', '.', '*', ':', ',', '@']



def scale_image(image, new_width=100):

    """Resizes an image preserving the aspect ratio.

    """

    (original_width, original_height) = image.size

    aspect_ratio = original_height/float(original_width)

    new_height = int(aspect_ratio * new_width)



    new_image = image.resize((new_width, new_height))

    return new_image



def convert_to_grayscale(image):

    return image.convert('L')



def map_pixels_to_ascii_chars(image, range_width=25):

    """Maps each pixel to an ascii char based on the range

    in which it lies.



    0-255 is divided into 11 ranges of 25 pixels each.

    """



    pixels_in_image = list(image.getdata())

    pixels_to_chars = [ASCII_CHARS[pixel_value//range_width] for pixel_value in

            pixels_in_image]



    return "".join(pixels_to_chars)



def convert_image_to_ascii(image, new_width=100):

    image = scale_image(image)

    image = convert_to_grayscale(image)



    pixels_to_chars = map_pixels_to_ascii_chars(image)

    len_pixels_to_chars = len(pixels_to_chars)



    image_ascii = [pixels_to_chars[index: index + new_width] for index in

            range(0, len_pixels_to_chars, new_width)]



    return "\n".join(image_ascii)



def handle_image_conversion(image_filepath):

    image = None

    try:

        image = Image.open(image_filepath)

    except Exception as e:

        print("Unable to open image file {image_filepath}.".format(image_filepath=image_filepath))

        print(e)

        return



    image_ascii = convert_image_to_ascii(image)

    f = open(os.path.splitext(image_filepath)[0]+'.txt','w')

    f.write(image_ascii)

    f.close()



if __name__=='__main__':

    import sys



    image_file_path = 'your_path/to_your_image/goes_here.png'

    handle_image_conversion(image_file_path)

puritan_communion, artist Alexander Reben