Raspberry Pi Zero 2 RTSP Server

Introduction

While setting up my smart home I was looking into creating a cost effective NVR that would allow for a high degree of privacy and control. The choice of NVR software fell on the excellent Frigate NVR, it integrates well with Home Assistant and supports hardware accelerated object detection via the little AI chip I had lying around.

The other part was having affordable, power-efficient camera hardware. There are many network-attached cameras on the market, but most of them require external services to set up/function and software wise they are black-boxes which raises considerable privacy concerns.

The choice fell on the Raspberry Pi Zero 2 running the default Raspberry Pi OS. The original Raspberry Pi Zero (v1) boards unfortunately are not suitable for streaming video in Full-HD, the CPUs were running at the limit and got too hot started heavily throttling. Fortunately the Raspberry Pi Zero 2 alleviated these issues at a similar price point (once they became available again in 2023/24).

The video to Frigate has to be an RTSP stream, to facilitate this we will be running MediaMTX via docker.

OS Setup

To set up the boot media for the Pi Zero we run Raspberry Pi imager

1. Click Choose device -> Raspberry Pi Zero 2 W.
2. Click Choose OS -> Raspberry Pi OS (other) -> Raspberry Pi OS (Legacy, 32 bit) Lite.
3. Click Choose Storage -> Select the SD Card.
4. Click Next -> Edit Settings.
5. Under General set desired hostname, credentials, etc.
6. Under Services -> Enable SSH. 7 Click Yes to create the boot media for the Pi Zero.

Now we transfer the Micro-SD card to the Raspberry Pi Zero with a connected camera.

Hardware check

We will do this part locally on the Raspberry Pi, so we need to connect a keyboard and display to it, for the Pi Zero we’ll need two adapters to connect a keyboard and a monitor:

• USB-A -> micro-USB
• HDMI -> micro-HDMI

Boot up the Pi Zero and wait for the initial file system resize to complete.

Once it reboots we can log in as the picam user and do a short test of whether the camera is recognized by the OS:

libcamera-hello

This should open a window on top of the terminal screen for a few seconds that shows the a camera feed.

Network Setup

We want to set a static IP that will persist on the SD Card in case I want to switch it over to another Raspberry Pi.

For this we edit the dhcp daemon config

sudo nano /etc/dhcpcd.conf

Towards the bottom we should see some commented out entries we can use. We just uncomment them and change the ip_address to our desired IP:

/etc/dhcpcd.conf

static ip_address=192.168.1.100/24
static routers=192.168.1.1
static domain_name_server=192.168.1.1

If there are any Raspberry Pi configurations we still want to change (e.g. enabling SSH in case we haven’t yet or setting the hostname)

Once we reboot we should be able to SSH into the machine

reboot

Upgrade/Install dependencies

We will install docker from the Debian repo after updating the OS packages:

sudo apt-get update
sudo apt-get upgrade -y
sudo apt-get install -y docker.io

Now we need to add the user to the docker group so it will have the right permissions

sudo usermod -aG docker admin
newgrp docker

RSTP Server setup

With docker set up we can now use it to run MediaMTX as the RTSP server, lets start it up:

docker run --rm -it --network=host --privileged --tmpfs /dev/shm:exec -v /run/udev:/run/udev:ro -e MTX-PATHS-CAM-SOURCE=rpiCamera bluenviron/mediamtx:latest-ffmpeg-rpi

Once we verified it runs correctly we can set up the service. Create a script to run it:

mkdir -p /home/admin/src/scripts
nano /home/admin/src/scripts/mediamtx.sh

with the following content (note, we’re removing -it from the above command for this script, as we don’t run an interactive shell for the service):

/home/admin/src/scripts/mediamtx.sh

#!/bin/bash
# Will be exposed at rtsp://[ip]:8554/cam
docker run --rm --network=host --privileged --tmpfs /dev/shm:exec -v /run/udev:/run/udev:ro -e MTX_PATHS_CAM_SOURCE=rpiCamera bluenviron/mediamtx:latest-ffmpeg-rpi

then make it executable:

chmod +x /home/admin/src/scripts/mediamtx.sh

Now we add the service:

sudo nano /etc/systemd/system/mediamtx.service

with:

/etc/systemd/system/mediamtx.service

[Unit]
Description=MediaMTX
After=network.target

[Service]
ExecStart=/home/admin/src/scripts/mediamtx.sh
Restart=always
RestartSec=3
User=admin
Group=docker

[Install]
WantedBy=default.target

Then we start it and activate startup on system start.

sudo systemctl daemon-reload
sudo systemctl start mediamtx
# Check logs to see if it starts up correctly
journalctl -u mediamtx -f
sudo systemctl enable mediamtx