Self-contained Raspberry Pi surveillance System Without Continue Internet

gemini generated

A self-contained Raspberry Pi surveillance system that:

Runs autonomously (like EyeOS) — camera always active and streaming.
Keeps searching for a known Wi-Fi hotspot (your phone).
Starts streaming automatically when the phone hotspot is available.
Lets you view the camera feed on your phone (via browser or app).

Here’s a detailed, production-ready setup:

⚙️ Step 1: Setup Raspberry Pi Camera & Software

1. Enable the camera

sudo raspi-config

Go to Interface Options → Camera → Enable
Reboot:

sudo reboot

2. Install dependencies

sudo apt update
sudo apt install python3-picamera2 python3-flask git -y

📸 Step 2: Create a Local Flask Streaming App

Create file /home/pi/camera_stream.py:

from flask import Flask, Response
from picamera2 import Picamera2
import time

app = Flask(__name__)
piCam = Picamera2()
piCam.configure(piCam.create_preview_configuration(main={"size": (640, 480)}))
piCam.start()

def gen_frames():
    while True:
        frame = piCam.capture_array()
        yield (b'--frame\r\n'
               b'Content-Type: image/jpeg\r\n\r\n' + 
               piCam.encode_jpeg(frame) + b'\r\n')

@app.route('/')
def index():
    return Response(gen_frames(), mimetype='multipart/x-mixed-replace; boundary=frame')

if __name__ == '__main__':
    app.run(host='0.0.0.0', port=8080)

Test it:

python3 /home/pi/camera_stream.py

Open in your phone browser (later):
http://:8080

🔁 Step 3: Auto-Connect to Your Phone’s Hotspot

Turn on your phone hotspot (note SSID & password).
Edit Wi-Fi config:

sudo nano /etc/wpa_supplicant/wpa_supplicant.conf

Add your phone hotspot details:

network={
    ssid="YourHotspotName"
    psk="YourHotspotPassword"
    priority=10
}

Add a Wi-Fi reconnect loop service to always search for it:

Create file /usr/local/bin/wifi_reconnect.sh:

#!/bin/bash
while true
do
    if ! iwgetid -r > /dev/null; then
        echo "No Wi-Fi. Trying to reconnect..."
        sudo wpa_cli -i wlan0 reconfigure
    fi
    sleep 15
done

Make it executable:

sudo chmod +x /usr/local/bin/wifi_reconnect.sh

🔄 Step 4: Autostart on Boot

Create systemd service /etc/systemd/system/camera.service:

[Unit]
Description=Camera Stream Service
After=network.target

[Service]
ExecStart=/usr/bin/python3 /home/pi/camera_stream.py
Restart=always
User=pi

[Install]
WantedBy=multi-user.target

And Wi-Fi watcher service /etc/systemd/system/wifi-reconnect.service:

[Unit]
Description=Wi-Fi Auto Reconnect

[Service]
ExecStart=/usr/local/bin/wifi_reconnect.sh
Restart=always
User=root

[Install]
WantedBy=multi-user.target

Enable both:

sudo systemctl enable camera.service
sudo systemctl enable wifi-reconnect.service
sudo systemctl start camera.service
sudo systemctl start wifi-reconnect.service

📱 Step 5: Access from Phone

When you enable your phone hotspot:

Pi connects automatically (within ~15s).
Visit http://192.168.43.x:8080 (Pi IP shown in hotspot device list).
You’ll see live camera feed.

💡 Optional Enhancements

Use ngrok or localtunnel to access remotely later (if internet is available).
Add motion detection with motion or opencv-python.
Use systemd watchdog or cron to reboot if Wi-Fi drops too long.

Here’s how to extend your setup to add motion detection + offline snapshot saving, all still working without internet and auto-starting when your phone hotspot appears.

⚙️ Step 6: Add Motion Detection with Snapshots

We’ll modify the Flask camera script to:

Continuously capture frames.
Compare each frame to detect movement.
Save snapshots locally when motion occurs.
Keep the live stream accessible at http://<pi_ip>:8080.

📄 Replace your `/home/pi/camera_stream.py` with this:

from flask import Flask, Response
from picamera2 import Picamera2
import cv2, numpy as np, time, os

app = Flask(__name__)
piCam = Picamera2()
piCam.configure(piCam.create_preview_configuration(main={"size": (640, 480)}))
piCam.start()

last_frame = None
save_path = "/home/pi/motion_captures"
os.makedirs(save_path, exist_ok=True)

def gen_frames():
    global last_frame
    while True:
        frame = piCam.capture_array()
        gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
        gray = cv2.GaussianBlur(gray, (21, 21), 0)

        if last_frame is None:
            last_frame = gray
            continue

        delta = cv2.absdiff(last_frame, gray)
        thresh = cv2.threshold(delta, 25, 255, cv2.THRESH_BINARY)[1]
        thresh = cv2.dilate(thresh, None, iterations=2)
        cnts, _ = cv2.findContours(thresh, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_SIMPLE)

        for c in cnts:
            if cv2.contourArea(c) < 1500:  # ignore small movements
                continue
            timestamp = time.strftime("%Y%m%d-%H%M%S")
            filename = f"{save_path}/motion_{timestamp}.jpg"
            cv2.imwrite(filename, frame)
            print(f"Motion detected, snapshot saved: {filename}")
            time.sleep(1)  # avoid saving too many per second
            break

        last_frame = gray

        # Stream JPEG frame
        _, jpeg = cv2.imencode('.jpg', frame)
        yield (b'--frame\r\n'
               b'Content-Type: image/jpeg\r\n\r\n' + jpeg.tobytes() + b'\r\n')

@app.route('/')
def index():
    return Response(gen_frames(), mimetype='multipart/x-mixed-replace; boundary=frame')

if __name__ == '__main__':
    app.run(host='0.0.0.0', port=8080)

🗂️ Step 7: Verify Motion Capture Folder

All motion-triggered snapshots will be stored in:

/home/pi/motion_captures/

You can access them later using:

ls /home/pi/motion_captures/

Or even download them through SFTP from your phone if you use an app like CX File Explorer or Termius.

🌀 Step 8: Auto-Restart Service (if not already)

Your existing systemd service (camera.service) already keeps this running on boot and restart.
Just restart it once to load the new version:

sudo systemctl restart camera.service

✅ Final Behavior

Raspberry Pi boots up and keeps scanning for your phone’s hotspot.
Once your hotspot is on, it connects automatically.
The Flask camera service starts streaming on http://192.168.43.x:8080.
Any motion triggers snapshots saved under /home/pi/motion_captures/.
Works completely offline.

Think Different