app.py

import streamlit as st
import requests
import base64
from PIL import Image, ImageOps, ImageDraw
from io import BytesIO
import re

def process_image(image_data, is_base64=False):
    try:
        if is_base64:
            # Remove potential base64 headers (like 'data:image/png;base64,')
            image_data = re.sub(r"^data:image/\w+;base64,", "", image_data)
            image_data = base64.b64decode(image_data)
        
        image = Image.open(BytesIO(image_data)).convert("RGB")

        # Convert to negative
        negative = ImageOps.invert(image)

        # Draw a red circular dot in the center
        draw = ImageDraw.Draw(negative)
        width, height = negative.size
        dot_radius = max(width, height) // 50  # Dynamic dot size
        center_x, center_y = width // 2, height // 2
        draw.ellipse(
            (center_x - dot_radius, center_y - dot_radius, center_x + dot_radius, center_y + dot_radius),
            fill=(255, 0, 0)
        )

        return negative
    except Exception as e:
        st.error(f"Error processing image: {e}")
        return None

def main():
    st.title("Negative Effect for Image")

    input_method = st.radio("Select Image Input Method:", ("Direct Image URL", "Base64 Image"))

    img = None  # Ensure img is always defined

    if input_method == "Direct Image URL":
        image_url = st.text_input("Enter Image URL:")
        if image_url:
            try:
                response = requests.get(image_url, stream=True)
                response.raise_for_status()
                img = process_image(response.content)
            except Exception as e:
                st.error(f"Error fetching image: {e}")

    elif input_method == "Base64 Image":
        base64_image = st.text_area("Enter Base64 Encoded Image:")
        if base64_image.strip():
            try:
                img = process_image(base64_image, is_base64=True)
            except Exception as e:
                st.error(f"Error processing base64 image: {e}")

    if img is not None:
        st.image(img, caption="Processed Image", use_column_width=True)
    else:
        st.warning("Please provide a valid image input.")

if __name__ == "__main__":
    main()