app.py

import logging
import queue
from typing import List, NamedTuple
import av
import cv2
import numpy as np
import streamlit as st
from streamlit_webrtc import WebRtcMode, webrtc_streamer
from sample_utils.turn import get_ice_servers
import mediapipe as mp
import os
import time

# Logger Setup
logger = logging.getLogger(__name__)

# Streamlit settings
st.set_page_config(page_title="Virtual Keyboard", page_icon="🏋️")
st.title("Interactive Virtual Keyboard")
st.subheader('''Turn on the webcam and use hand gestures to interact with the virtual keyboard.
Use 'a' and 'd' from the keyboard to change the background.''')

# Initialize MediaPipe and Background Segmentor
mp_hands = mp.solutions.hands
hands = mp_hands.Hands(max_num_hands=1, min_detection_confidence=0.5)
mp_drawing = mp.solutions.drawing_utils

# Virtual Keyboard Layout
keys = [["Q", "W", "E", "R", "T", "Y", "U", "I", "O", "P"],
        ["A", "S", "D", "F", "G", "H", "J", "K", "L", ";"],
        ["Z", "X", "C", "V", "B", "N", "M", ",", ".", "/"]]

class Button:
    def __init__(self, pos, text, size=[100, 100]):
        self.pos = pos
        self.size = size
        self.text = text

class Detection(NamedTuple):
    label: str
    score: float
    box: np.ndarray

result_queue: "queue.Queue[List[Detection]]" = queue.Queue()


indexImg = 0
output_text = ""
prev_key_time = [time.time()] * 2

if "output_text" not in st.session_state:
    st.session_state["output_text"] = ""

# Video Frame Callback with Your Logic
def video_frame_callback(frame: av.VideoFrame) -> av.VideoFrame:
    global indexImg, output_text

    img = frame.to_ndarray(format="bgr24")

    # Process frame using MediaPipe
    result = hands.process(cv2.cvtColor(img, cv2.COLOR_BGR2RGB))

    buttonList = [Button([30 + col * 105, 30 + row * 120], key) for row, line in enumerate(keys) for col, key in enumerate(line)]
    for button in buttonList:
        x, y = button.pos
        w, h = button.size
        if x < x8 < x + w and y < y8 < y + h:
            cv2.rectangle(img, button.pos, (x + w, y + h), (0, 255, 160), -1)
            cv2.putText(img, button.text, (x + 20, y + 70), cv2.FONT_HERSHEY_PLAIN, 5, (255, 255, 255), 3)

    detections = []
    if result.multi_hand_landmarks:
        for hand_landmarks in result.multi_hand_landmarks:
            # Draw hand landmarks
            mp_drawing.draw_landmarks(
                img, hand_landmarks, mp_hands.HAND_CONNECTIONS,
                mp_drawing.DrawingSpec(color=(0, 255, 0), thickness=2, circle_radius=4),
                mp_drawing.DrawingSpec(color=(0, 0, 255), thickness=2)
            )

            # Extract bounding box for each hand
            h, w, _ = img.shape
            x_min, y_min = w, h
            x_max, y_max = 0, 0
            for lm in hand_landmarks.landmark:
                x, y = int(lm.x * w), int(lm.y * h)
                x_min, y_min = min(x_min, x), min(y_min, y)
                x_max, y_max = max(x_max, x), max(y_max, y)

            bbox = [x_min, y_min, x_max - x_min, y_max - y_min]
            detections.append(Detection(label="Hand", score=1.0, box=np.array(bbox)))

            # Extract finger tip positions
            x4, y4 = int(hand_landmarks.landmark[mp_hands.HandLandmark.THUMB_TIP].x * w), int(hand_landmarks.landmark[mp_hands.HandLandmark.THUMB_TIP].y * h)
            x8, y8 = int(hand_landmarks.landmark[mp_hands.HandLandmark.INDEX_FINGER_TIP].x * w), int(hand_landmarks.landmark[mp_hands.HandLandmark.INDEX_FINGER_TIP].y * h)

            
            # Distance Calculation
            distance = np.sqrt((x8 - x4) ** 2 + (y8 - y4) ** 2)
            click_threshold = 10


                    # Simulate key press if finger close enough
                    if (distance / np.sqrt(bbox[2] ** 2 + bbox[3] ** 2)) * 100 < click_threshold:
                        if time.time() - prev_key_time[0] > 2:
                            prev_key_time[0] = time.time()
                            if button.text != 'BS' and button.text != 'SPACE':
                                output_text += button.text
                            elif button.text == 'BS':
                                output_text = output_text[:-1]
                            else:
                                output_text += ' '

    result_queue.put(detections)
    st.session_state["output_text"] = output_text
    return av.VideoFrame.from_ndarray(img, format="bgr24")

# WebRTC Streamer
webrtc_streamer(
    key="virtual-keyboard",
    mode=WebRtcMode.SENDRECV,
    rtc_configuration={"iceServers": get_ice_servers(), "iceTransportPolicy": "relay"},
    media_stream_constraints={"video": True, "audio": False},
    video_frame_callback=video_frame_callback,
    async_processing=True,
)