Steganographic Encoding

Question

This is my code for encoding and decoding. However it didn't give me the expected results when I tried to decode the stago.jpg online.

I got this result from online decoder: ¶Ûm¶Ûm¶Ûm¶Ûm¶Ûm¶Ûm¶Ûm¶Ûm¶Ûm¶Ûm¶Ûm¶Ûm¶Ûm¶Ûm¶...

from PIL import Image
import os

Encoding Code:

# Encoding
def encode_text_to_image(cover_image_path, payload_text, output_image_path, numLSB):
    cover_image = Image.open(cover_image_path)
    width, height = cover_image.size

    # Convert the payload text to binary
    payload_bytes = payload_text.encode('utf-8')
    payload_length = len(payload_bytes)

    # Ensure that the payload can fit within the cover image
    max_payload_length = (width * height * 3 * numLSB) // 8
    if payload_length > max_payload_length:
        raise ValueError("Payload text is too large for the cover image")

    # Add payload length metadata to the binary payload
    binary_payload = format(payload_length, '032b')

    # Iterate over each pixel in the cover image
    index = 0
    for y in range(height):
        for x in range(width):
            if index < len(binary_payload):
                # Get the RGB values of the current pixel
                r, g, b = cover_image.getpixel((x, y))

                # Modify the least significant bits of each RGB value
                for i in range(numLSB):
                    mask = 1 << i
                    if index < len(binary_payload):
                        r = (r & ~mask) | (int(binary_payload[index]) << i)
                        index += 1

                # Set the modified RGB values in the cover image
                cover_image.putpixel((x, y), (r, g, b))

            elif index - len(binary_payload) < payload_length * 8:
                # Get the RGB values of the current pixel
                r, g, b = cover_image.getpixel((x, y))

                # Modify the least significant bits of each RGB value using payload bytes
                for i in range(numLSB):
                    mask = 1 << i
                    if index - len(binary_payload) < payload_length * 8:
                        byte_index = (index - len(binary_payload)) // 8
                        bit_index = (index - len(binary_payload)) % 8
                        payload_byte = payload_bytes[byte_index]
                        payload_bit = (payload_byte >> (7 - bit_index)) & 1
                        r = (r & ~mask) | (payload_bit << i)
                        index += 1

                # Set the modified RGB values in the cover image
                cover_image.putpixel((x, y), (r, g, b))

    # Save the steganographic image
    cover_image.save(output_image_path)