app.py

import streamlit as st
import cv2
import numpy as np
from PIL import Image
import io

st.set_page_config(page_title="Colorize Image", page_icon="🎨", layout="centered")
st.title("🎨 Colorize Your Image")
st.markdown("Upload an image and apply a color tint dynamically!")

# Upload Image
uploaded_file = st.file_uploader("Upload an Image", type=["png", "jpg", "jpeg", "webp"])

if uploaded_file is not None:
    # Convert image to OpenCV format
    image = Image.open(uploaded_file)
    image = np.array(image)

    # Ensure the image has 3 channels (RGB)
    if len(image.shape) == 2:  # Convert grayscale to RGB
        image = cv2.cvtColor(image, cv2.COLOR_GRAY2RGB)
    elif image.shape[-1] == 4:  # Convert RGBA to RGB
        image = cv2.cvtColor(image, cv2.COLOR_RGBA2RGB)

    st.image(image, caption="Original Image", use_column_width=True)

    # Select Tint Color
    st.subheader("Select Tint Color")
    tint_color = st.color_picker("Pick a tint color", "#ff0000")  # Default Red

    # Convert Hex to RGB
    hex_color = tint_color.lstrip("#")
    tint_rgb = tuple(int(hex_color[i:i+2], 16) for i in (0, 2, 4))

    # Intensity Slider
    intensity = st.slider("Tint Intensity", 0, 100, 50)

    # Colorize Function
    def apply_tint(img, color, intensity):
        # Convert to grayscale
        gray = cv2.cvtColor(img, cv2.COLOR_RGB2GRAY)
        gray = cv2.cvtColor(gray, cv2.COLOR_GRAY2RGB)  # Convert back to 3 channels

        # Create color overlay
        color_overlay = np.full_like(gray, color, dtype=np.uint8)

        # Blend grayscale with color overlay
        blended = cv2.addWeighted(gray, 1 - (intensity / 100), color_overlay, intensity / 100, 0)
        return blended

    # Apply Tint
    modified_image = apply_tint(image, tint_rgb, intensity)
    st.image(modified_image, caption="Tinted Image", use_column_width=True)

    # Download Button
    img_byte_arr = io.BytesIO()
    Image.fromarray(modified_image).save(img_byte_arr, format="PNG")
    st.download_button("Download Tinted Image", img_byte_arr.getvalue(), file_name="tinted_image.png", mime="image/png")

st.markdown("---")
st.markdown("💡 Developed with ❤️ using Streamlit, OpenCV, and NumPy")