app.py

import cv2
import streamlit as st
from streamlit_webrtc import webrtc_streamer, WebRtcMode, VideoHTMLAttributes
import numpy as np
import av

st.title("OpenCV Filters on Video Stream")

# Define the filter state variable
filter = "none"

def transform(frame: av.VideoFrame):
    img = frame.to_ndarray(format="bgr24")

    # Apply the selected filter
    if filter == "blur":
        img = cv2.GaussianBlur(img, (21, 21), 0)
    elif filter == "canny":
        img = cv2.cvtColor(cv2.Canny(img, 100, 200), cv2.COLOR_GRAY2BGR)
    elif filter == "grayscale":
        img = cv2.cvtColor(cv2.cvtColor(img, cv2.COLOR_BGR2GRAY), cv2.COLOR_GRAY2BGR)
    elif filter == "sepia":
        kernel = np.array([[0.272, 0.534, 0.131], [0.349, 0.686, 0.168], [0.393, 0.769, 0.189]])
        img = cv2.transform(img, kernel)
    elif filter == "invert":
        img = cv2.bitwise_not(img)
    
    # Debugging: Check if the frame is being processed
    print(f"Processing frame with filter: {filter}")
    
    return av.VideoFrame.from_ndarray(img, format="bgr24")

# Streamlit buttons to choose filters
col1, col2, col3, col4, col5, col6 = st.columns([1, 1, 1, 1, 1, 1])

with col1:
    if st.button("None"):
        filter = "none"
with col2:
    if st.button("Blur"):
        filter = "blur"
with col3:
    if st.button("Grayscale"):
        filter = "grayscale"
with col4:
    if st.button("Sepia"):
        filter = "sepia"
with col5:
    if st.button("Canny"):
        filter = "canny"
with col6:
    if st.button("Invert"):
        filter = "invert"

# WebRTC constraints for video resolution (optional)
video_constraints = {
    "facing_mode": "user",  # Use the front camera
    "width": {"ideal": 1280},
    "height": {"ideal": 720}
}

# Display the video stream
webrtc_streamer(
    key="streamer",
    video_frame_callback=transform,
    sendback_audio=False,
    video_constraints=video_constraints,  # Optional: set constraints
    mode=WebRtcMode.SENDRECV  # Ensure bidirectional communication (send/receive video)
)