Render images from Krux flash dumps

krux_flash_viewer.py

import os
import tkinter as tk
from tkinter import filedialog
from PIL import Image, ImageTk

def create_image_from_file(filename, start_pos):
    def maxv(number_of_bits):
        return (2**number_of_bits) - 1
    
    with open(filename, 'rb') as f:
        f.seek(start_pos)
        data = f.read(153600)  # Read 153,600 bytes

    # Ensure we have enough data to form an image
    if len(data) < 153600:
        # Pad the remaining bytes with zeros if needed
        data += b'\x00' * (153600 - len(data))

    pixels = []
    for i in range(0, len(data), 2):
        byte1 = data[i]
        byte2 = data[i+1]
        rgb_int = (byte1 << 8) | byte2

        # big = True

        # rgb_int = int.from_bytes(rgb, "big" if big else "little")

        # left 5 bits of red multiplied to fill 8 bit space
        r = round((rgb_int >> 11) * maxv(8) / maxv(5))

        # middle 6 bits of green multiplied to fill 8 bit space
        g = round(((rgb_int & maxv(11)) >> 5) * maxv(8) / maxv(6))

        # right 5 bits of blue multiplied to fill 8 bit space
        b = round((rgb_int & maxv(5)) * maxv(8) / maxv(5))

        pixels.append((r, g, b))

    # Create an image from the pixel data
    image = Image.new('RGB', (320, 240))
    image.putdata(pixels)
    return image

def main():
    root = tk.Tk()
    root.title("Krux Flash Viewer")

   # Ask user for filename
    filename = filedialog.askopenfilename(title="Select binary file")

    if not filename:
        print("No file selected")
        return

    # Get the file size
    file_size = os.path.getsize(filename)

    # Calculate the maximum start position (must be multiple of 2)
    max_start_pos = (file_size - 153600) // 2 * 2
    if max_start_pos < 0:
        max_start_pos = 0

    # Create a label to hold the image
    label = tk.Label(root)
    label.pack(side='left')

    # Create a scrollbar (Scale widget)
    # The range is from 0 to max_start_pos // 2 to ensure positions are multiples of 2
    scale = tk.Scale(
        root,
        from_=0,
        to=max_start_pos // 640,
        orient='vertical',
        length=400,
        command=lambda val: update_image(int(val) * 640)
    )
    scale.pack(side='right', fill='y')

    def update_image(position):
        # Read and display the image starting from the given position
        image = create_image_from_file(filename, position)
        photo = ImageTk.PhotoImage(image)
        label.config(image=photo)
        label.image = photo  # Keep a reference to prevent garbage collection

    # Initialize the display with the starting position 0
    update_image(0)

    root.mainloop()

if __name__ == '__main__':
    main()