Update app.py

app.py

@@ -62,20 +62,46 @@ def encrypt_image(img_array, seed):
 
     return doubly_encrypted_array
 
+# Decrypt function
+def decrypt_image(encrypted_array, seed, original_shape):
+    h, w, c = original_shape
+    flat_image = encrypted_array.flatten()
+
+    # Generate the second chaotic key
+    chaotic_key_2 = generate_key(seed * 1.1, len(flat_image))
+    
+    # Reverse the second XOR encryption
+    xor_reversed_flat = [pixel ^ chaotic_key_2[i] for i, pixel in enumerate(flat_image)]
+    xor_reversed_array = np.array(xor_reversed_flat, dtype=np.uint8).reshape(h, w, c)
+
+    # Reverse pixel shuffling
+    shuffled_array = xor_reversed_array
+    num_pixels = h * w
+    flattened = shuffled_array.reshape(-1, c)
+    indices = np.arange(num_pixels)
+    
+    random.seed(seed)
+    random.shuffle(indices)  # Reuse the same shuffle logic
+    unshuffled = np.zeros_like(flattened)
+    unshuffled[indices] = flattened
+    unshuffled_array = unshuffled.reshape(h, w, c)
+
+    # Generate the first chaotic key
+    chaotic_key_1 = generate_key(seed, len(flat_image))
+
+    # Reverse the first XOR encryption
+    decrypted_flat = [pixel ^ chaotic_key_1[i] for i, pixel in enumerate(unshuffled_array.flatten())]
+    decrypted_array = np.array(decrypted_flat, dtype=np.uint8).reshape(h, w, c)
+
+    return decrypted_array
+
 # Streamlit App
 def main():
     st.title("Enhanced Chaotic Logistic Map Image Encryption")
-    st.write("Upload an image to encrypt using advanced chaotic logistic map methods.")
+    st.write("Upload an image to encrypt and decrypt using advanced chaotic logistic map methods.")
 
     uploaded_file = st.file_uploader("Upload an image", type=["jpg", "jpeg", "png"])
     if uploaded_file is not None:
-        with st.spinner("Processing upload..."):
-            # Simulate a loading delay for upload progress
-            progress_bar = st.progress(0)
-            for percent_complete in range(0, 101, 20):
-                time.sleep(0.1)  # Simulate progress
-                progress_bar.progress(percent_complete)
-
         # Load the uploaded image
         input_image = Image.open(uploaded_file)
 
@@ -93,13 +119,6 @@ def main():
 
         if st.button("Encrypt Image"):
             with st.spinner("Encrypting image..."):
-                # Simulate a loading delay for encryption progress
-                progress_bar = st.progress(0)
-                for percent_complete in range(0, 101, 20):
-                    time.sleep(0.1)  # Simulate progress
-                    progress_bar.progress(percent_complete)
-
-                # Encrypt the image
                 encrypted_array = encrypt_image(img_array, key_seed)
                 encrypted_image = Image.fromarray(encrypted_array)
 
@@ -119,5 +138,13 @@ def main():
                     mime="image/png"
                 )
 
+        if st.button("Decrypt Image"):
+            with st.spinner("Decrypting image..."):
+                decrypted_array = decrypt_image(encrypted_array, key_seed, img_array.shape)
+                decrypted_image = Image.fromarray(decrypted_array)
+
+                # Display decrypted image
+                st.image(decrypted_image, caption="Decrypted Image", use_container_width=True)
+
 if __name__ == "__main__":
     main()