app.py

import subprocess
import os
import streamlit as st
from PIL import Image
from cryptography.hazmat.primitives.ciphers import Cipher, algorithms, modes
from cryptography.hazmat.backends import default_backend

# Install altair if not already installed
try:
    import altair
except ImportError:
    subprocess.run(["pip", "install", "altair==4.1.0"])
    import altair  # Import again after installation

class CBCEncryption:
    # Your CBCEncryption class code here...

def encrypt_image(encryption, image_path, output_path):
    # Your encrypt_image function code here...

def decrypt_image(decryption, image_path, output_path):
    # Your decrypt_image function code here...

def unpad_data(data):
    # Your unpad_data function code here...

def main():
    st.title("AES CBC Encryption/Decryption")

    uploaded_file = st.file_uploader("Choose an image...", type=["bmp", "png", "jpg", "jpeg"])
    key = st.text_input("Enter Key:", type="password")

    if uploaded_file is not None and key:
        st.write("")  # Add space between encryption and decryption options
        encrypt_button = st.button("Encrypt Image")
        decrypt_button = st.button("Decrypt Image")

        key = key.encode('utf-8')
        key = key.ljust(32, b'\x35')
        iv = key[:16]
        iv = bytearray(iv)
        for i in range(16):
            iv[i] = iv[i] ^ 0x35
        iv = bytes(iv)

        AesCbc = CBCEncryption(key, iv)
        
        image_path = 'uploaded_image.bmp'
        output_path = 'output_image.bmp'
        
        with open(image_path, 'wb') as f:
            f.write(uploaded_file.getbuffer())
        
        if encrypt_button:
            encrypt_image(encryption=AesCbc, image_path=image_path, output_path=output_path)
            st.success("Encryption done!")
            with open(output_path, 'rb') as f:
                st.download_button(label="Download Encrypted Image", data=f, file_name="encrypted_image.bmp")
        
        elif decrypt_button:
            decrypt_image(decryption=AesCbc, image_path=image_path, output_path=output_path)
            st.success("Decryption done!")
            decrypted_image = Image.open(output_path)
            st.image(decrypted_image, caption="Decrypted Image")

if __name__ == '__main__':
    main()