im2c

#!/bin/env python3

########################################################################
## PIC ADI Image 2 C Array Converter
##
## Author: Michael R. Shannon
##
## This program is meant to be called from the command line.
##
########################################################################


import sys
from PIL import Image
from bitarray import bitarray


def to_array(filename):
    """Load monochrome image into a bitarray."""
    bit_array = bitarray(endian="little")
    with Image.open(filename) as im:
        pixels = im.load()
        for i in range(0, im.size[0]):
            for j in range(0, im.size[1]):
                bit_array.append(pixels[i, j] != 0)
    return bit_array.tobytes()


def chunks(array, length):
    """Turn array into iterable of given chunk length."""
    chunk = [None]*length
    idx = 0
    for v in array:
        chunk[idx] = v
        idx = (idx + 1) % length
        if idx == 0:
            yield chunk


def print_array(array):
    """Print array as a C style uint8_t array of size OLED_SIZE."""
    print("uint8_t frameBuffer[OLED_SIZE] = {")
    for line in chunks(array, 8):
        print(("   " + " 0x{:02X},"*8).format(*line))
    print("};")


def check_size(filename):
    """Make sure image given by <filename> is 128x64 pixels."""
    with Image.open(filename) as im:
        if im.size != (128, 64):
            print("Expected image of 128x64, got {}x{}".format(*im.size))
            return True
    return False


def convert_image(filename):
    """Convert monochrome image given by <filename> and print C array."""
    if check_size(filename):
        return
    byte_array = to_array(filename)
    print_array(byte_array)


if __name__ == "__main__":
    """Handle parsing of filename from terminal argument and convert."""
    try:
        filename = sys.argv[1]
    except IndexError:
        print("{} expects at least one argument".format(sys.argv[0]))
    convert_image(filename)