img_to_slack_emoji.py

"""Converts image to IMAGE_SIZExIMAGE_SIZE slack emoji array"""

import sys
import numpy

from PIL import Image

EMOJI_MAP = [
    # enter custom emoji map here (dark one first)
    # ':desktop_computer:',
    # ':floppy_disk:',
    # ':unicorn_face:',
]
EMOJI_LENGTH = len(EMOJI_MAP)

IMAGE_FILEPATH = './image.png'
IMAGE_SIZE = 20

def jpg_image_to_array(image_path):
    """
    Loads JPEG image into 3D Numpy array of shape
    (width, height, channels)
    """
    with Image.open(image_path).convert('L') as image:
        image.thumbnail((IMAGE_SIZE, IMAGE_SIZE,), Image.NEAREST)
        im_arr = numpy.array(image.getdata())
        im_arr = im_arr.reshape((image.size[1], image.size[0]))

    return im_arr


def normalize_array(im_arr):
    # normalize
    th = int(256 / (EMOJI_LENGTH + 1))

    for i, row in enumerate(im_arr):
        for j, val in enumerate(row):

            for k in range(EMOJI_LENGTH):
                if val <= th * (k + 1):
                    im_arr[i][j] = k
                    break

            if val > th * EMOJI_LENGTH:
                im_arr[i][j] = (EMOJI_LENGTH - 1)

    return im_arr



if __name__ == '__main__':
    pixels = normalize_array(jpg_image_to_array(IMAGE_FILEPATH))

    # print(ar)
    # ar = [
    #   [0,0,1,0,0,0,0],
    #   [0,0,1,0,0,0,0],
    #   [0,0,1,1,1,0,0],
    #   [1,1,1,1,1,1,0],
    #   [1,1,1,1,1,0,0],
    #   [1,1,1,1,1,1,0],
    #   [1,1,1,1,1,0,0],
    # ]

    for row in pixels:
        for cell in row:
            sys.stdout.write(EMOJI_MAP[cell])
        sys.stdout.write('\n')

    sys.stdout.flush()