Decoder.py

from PIL import Image, ImageDraw
import struct

output = "binary_file.bin"  # File to bin uncompressed bite code
Input = "kodim23.qoi" # .qoi file u want to decode
photosafe = "output.png"  # file to safe .png

output = open(output, mode="wb")
f = open(Input, mode="rb")

class Pixel:
    def __init__(self, r=0, g=0, b=0, a=255):
        self.r = r
        self.g = g
        self.b = b
        self.a = a

    def getIndexPosition(self):
        return (self.r * 3 + self.g * 5 + self.b * 7 + self.a * 11) % 64

    def __str__(self):
        return f"Pixel (R: {self.r}, G: {self.g}, B: {self.b}, A: {self.a})"

    def wraparound(self):
        if self.r > 255:
            self.r -= 256
        if self.r < 0:
            self.r += 256

        if self.b > 255:
            self.b -= 256
        if self.b < 0:
            self.b += 256
        if self.g > 255:
            self.g -= 256
        if self.g < 0:
            self.g += 256
        if self.a > 255:
            self.a -= 256
        if self.a < 0:
            self.a += 256

    def writeToBin(self, file):
        binary_data = self.r.to_bytes(1, 'big')
        file.write(binary_data)
        binary_data = self.g.to_bytes(1, 'big')
        file.write(binary_data)
        binary_data = self.b.to_bytes(1, 'big')
        file.write(binary_data)
        binary_data = self.a.to_bytes(1, 'big')

        file.write(binary_data)


# Reading file data with read() method
data = f.read()
header = data[0:14]
body = data[14:]

# Knowing the Type of our data
QOIF = header[0:4]

if QOIF != b'qoif':
    f.close()
    raise Exception("This is not a qoi file")

width = int.from_bytes(header[4:8], byteorder='big')
height = int.from_bytes(header[8:12], byteorder='big')
image = Image.new("RGBA", (width, height))
binary_data = width.to_bytes(4, 'big')
output.write(binary_data)
print()
binary_data = height.to_bytes(4, 'big')
output.write(binary_data)

draw = ImageDraw.Draw(image)
channels = int.from_bytes(header[12:13], byteorder='big')
colorspace = int.from_bytes(header[13:14], byteorder='big')
print(width, height)
print(body[:14].hex())
if channels == 3:
    print("Channels: ", "RGB")
elif channels == 4:
    print("Channels: ", "RGBA")
if colorspace == 0:
    print("colorspace: ", "sRGB with linear alpha")
elif colorspace == 1:
    print("colorspace: ", "all channels linear")
seenPixels = {}
for i in range(64):
    seenPixels[i] = Pixel(0, 0, 0, 0)
index = 0
prevPixel = Pixel()
column = 0
row = 0
while index < len(body):
    byte = body[index]

    currentPixel = Pixel()
    currentPixel.a = prevPixel.a

    if byte == 254:
        currentPixel.r = body[index + 1]
        currentPixel.g = body[index + 2]
        currentPixel.b = body[index + 3]
        currentPixel.a = prevPixel.a
        index += 3

    elif byte == 255:
        currentPixel.r = body[index + 1]
        currentPixel.g = body[index + 2]
        currentPixel.b = body[index + 3]
        currentPixel.a = body[index + 4]
        index += 4

    elif byte < 64:  # starts with 00
        if byte in seenPixels:
            currentPixel.r = seenPixels[byte].r
            currentPixel.g = seenPixels[byte].g
            currentPixel.b = seenPixels[byte].b
            currentPixel.a = seenPixels[byte].a

        else:
            # Handle case when pixel index is not found
            print("Pixel index not found in seenPixels dictionary.", index, byte)
    elif byte < 128:
        red_diff = ((byte >> 4) & 0b11) - 2
        green_diff = ((byte >> 2) & 0b11) - 2
        blue_diff = (byte & 0b11) - 2
        currentPixel.r = red_diff + prevPixel.r
        currentPixel.g = green_diff + prevPixel.g
        currentPixel.b = blue_diff + prevPixel.b
        currentPixel.a = prevPixel.a
    elif byte < 192:
        byte2 = body[index + 1]
        index = index + 1
        vg = (byte & 0x3f) - 32
        currentPixel.r = prevPixel.r + vg - 8 + ((byte2 >> 4) & 0b1111)
        currentPixel.g = prevPixel.g + vg
        currentPixel.b = prevPixel.b + vg - 8 + ((byte2) & 0b1111)


    else:
        currentPixel.r = prevPixel.r
        currentPixel.g = prevPixel.g
        currentPixel.b = prevPixel.b
        currentPixel.a = prevPixel.a

        if body[index] >> 6 != 3:
            print("IETS MIS")
        run = body[index] & 0b111111

        for i in range(run):
            currentPixel.writeToBin(output)

            if column < width and row < height:
                image.putpixel((column, row), (currentPixel.r, currentPixel.g, currentPixel.b, currentPixel.a))
            column += 1
            if column >= width:
                column = 0
                row += 1

            seenPixels[currentPixel.getIndexPosition()] = Pixel(currentPixel.r, currentPixel.g, currentPixel.b,
                                                                currentPixel.a)

    currentPixel.wraparound()
    currentPixel.writeToBin(output)

    if column < width and row < height:
        image.putpixel((column, row), (currentPixel.r, currentPixel.g, currentPixel.b, currentPixel.a))
    column += 1
    if column >= width:
        column = 0
        row += 1
    seenPixels[currentPixel.getIndexPosition()] = Pixel(currentPixel.r, currentPixel.g, currentPixel.b, currentPixel.a)
    prevPixel = Pixel(currentPixel.r, currentPixel.g, currentPixel.b, currentPixel.a)
    index += 1
print(width, row, column)
image.show()
image.save(photosafe)
f.close()
output.close()