Building a Mobile Video Surveillance App with RTSP and ONVIF Integration

// Android: WS-Discovery multicast class ONVIFDiscovery { private val MULTICAST_ADDRESS = "239.255.255.250" private val MULTICAST_PORT = 3702 suspend fun discoverDevices(timeout: Long = 3000): List<ONVIFDevice> { val socket = MulticastSocket(MULTICAST_PORT) socket.joinGroup(InetAddress.getByName(MULTICAST_ADDRESS)) socket.soTimeout = timeout.toInt() val probeMessage = buildWSDiscoveryProbe() val packet = DatagramPacket( probeMessage.toByteArray(), probeMessage.length, InetAddress.getByName(MULTICAST_ADDRESS), MULTICAST_PORT ) socket.send(packet) val devices = mutableListOf<ONVIFDevice>() val buffer = ByteArray(4096) try { while (true) { val response = DatagramPacket(buffer, buffer.size) socket.receive(response) parseWSDiscoveryResponse(String(response.data, 0, response.length)) ?.let { devices.add(it) } } } catch (e: SocketTimeoutException) { /* normal */ } socket.close() return devices } } 

To obtain the RTSP URL: SOAP request GetStreamUri with WS-Security (Digest auth). The onvif4java library simplifies, but often lags behind current camera firmware — we prefer writing a custom SOAP client on Retrofit with a custom converter.

Multi-Camera Viewing

A grid of 4 or 9 simultaneous cameras is a heavy task. Each RTSP stream requires a separate decoder. On Android with 9 Full HD cameras, we risk exhausting hardware decoders (typically 4–8 per chip); the rest fall back to software decoding, dropping FPS to 5–10.

Solution: For the grid, use MJPEG snapshots via ONVIF GetSnapshotUri, updating every 2–3 seconds instead of full video streams. Full RTSP is activated only when tapping a camera to enter full-screen mode. This balances load and informativeness.

Recording and History: Local and Cloud Storage

Recording clips from the camera to the phone: download via ONVIF GetRecordings or ISAPI (Hikvision). Store locally in MediaStore (Android 10+) or Photos Library (iOS). For cloud cameras, direct MP4 links from the manufacturer's cloud.

Motion detection: either hardware-based (in the camera, events via ONVIF Event Service) or software-based on the mobile by comparing YUV differences between frames. Hardware detection is more reliable — fewer false alarms.

What's Included in Development

• Analysis of camera models and ONVIF compatibility
• Protocol selection and RTSP stream configuration
• Multi-camera grid with MJPEG snapshots
• Integration of recording and motion detection
• Publication to App Store and Google Play
• Technical documentation and team training
• Post-release support (optional)

Step-by-Step RTSP Viewing Implementation

1. Check which protocols your cameras support (RTSP, ONVIF, HLS).
2. Choose a player: for Android — ExoPlayer with RTSP extension, for iOS — VLCKit or FFmpegKit.
3. Configure buffering for minimal latency (target under 500 ms).
4. Test on different cameras and network conditions.
5. For multi-camera modes, implement MJPEG snapshots to conserve resources.

Timelines and Costs

Development of a mobile app with RTSP viewing of a single camera and basic ONVIF control: 4–5 weeks (starting at $5,000). Multi-camera system with WS-Discovery, PTZ control, recording history, and push alerts for motion: 8–12 weeks ($15,000-$25,000). Costs are calculated individually after analyzing your camera models and storage requirements. Using off-the-shelf libraries saves up to 40% of development time compared to building a custom RTSP client. Get a consultation for your project — we'll estimate timelines and costs.

Our experience in video surveillance app development spans over 50 successful projects for Hikvision, Dahua, Axis, Reolink cameras. We guarantee compliance with App Store Review Guidelines (Sections 4.2/5.1) and data security.