Python script to convert TJC TFT RLE encoded images to raw RGB565

TFTRLE2RGB565.py

import argparse
import os
from pathlib import Path
import struct


if __name__ == "__main__":
    desc = """TFT RLE to RGB5656 image converter
              Developped by Clark Scheff, licensed under GPLv3"""
    parser = argparse.ArgumentParser(description=desc)
    parser.add_argument("-i", "--input", metavar="IN_FILE", type=str, required=True,
                        help="Path to the RLE image file")
    parser.add_argument("-o", "--output", metavar="OUT_FILE", type=str, required=True,
                        help="Path to the RGB565 output image file")

args = parser.parse_args()

inPath = Path(args.input)
if not inPath.exists():
    parser.error("Invalid source file!")

outPath = Path(args.output)

with open(inPath, 'rb') as in_file:
    with open(outPath, 'wb') as out_file:
        header = in_file.read(20)
        compressed = header[0] != 0
        if not compressed:
            data = in_file.read()
            out_file.write(data)
        else:
            data_end = struct.unpack("I", header[4:8])[0]
            while in_file.tell() < data_end:
                counts = struct.unpack("I", in_file.read(4))[0]
                for i in range(8):
                    shift = 4 * i
                    count = (counts >> shift) & 0x0f
                    # if the first nibble is 0x0f we just write
                    # the colors as is to the output
                    if i == 0 and count == 0x0f:
                        for x in range(4):
                            colors = in_file.read(4)
                            out_file.write(colors)
                        break
                    color = bytearray(in_file.read(2))
                    for x in range(count):
                        out_file.write(color)