Native WebRTC use h264 hardware/software encoder on Raspberry Pi
Using v4l2 dma hardware encoder with WebRTC reduces CPU usage. Both signalr
and mqtt
are the options for signaling in this project.
boringssl
replace openssl
libwebrtc.a
microsoft-signalr
mosquitto
sudo apt install libboost-program-options-dev libavformat-dev libavcodec-dev libavutil-dev libswscale-dev libpulse-dev libasound2-dev libx11-dev
/usr/local/include
Command line |
Description | Valid values |
---|---|---|
-DUSE_SIGNALR_SIGNALING | Build the project by using SignalR as signaling. | ON, OFF |
-DUSE_MQTT_SIGNALING | Build the project by using MOSQUITTO as signaling. | ON, OFF |
-DBUILD_TEST | Build the test codes | recorder, mqtt, v4l2_capture, v4l2_encoder, v4l2_decoder, v4l2_scaler |
-DUSE_BUILT_IN_H264 | Use the built-in openh264 software encoder | ON, OFF |
Build on raspberry pi and it'll output a pi_webrtc
file in /build
.
mkdir build
cd build
cmake .. -DCMAKE_CXX_COMPILER=/usr/bin/clang++ -DUSE_MQTT_SIGNALING=ON
make -j
Run pi_webrtc
to start the service.
./pi_webrtc --device=/dev/video0 --fps=30 --width=1280 --height=720 --v4l2_format=mjpeg --signaling_url=http://localhost:6080/SignalingServer --enable_v4l2_dma
./pi_webrtc --device=/dev/video0 --fps=30 --width=1280 --height=720 --v4l2_format=mjpeg --mqtt_host=127.0.0.1 --mqtt_port=1883 --mqtt_username=<username> --mqtt_password=<password> --enable_v4l2_dma
./pi_webrtc -h
to list all available args.--enable_v4l2_dma
is assigned, only H264
stream is provided. The VP8
, VP9
are available as well if not be assigned. But frames will be decoded/scaled by software, and the buffer will be copied to the HW encoder though.--record_path
is assigned, the background recorder will start immediately after running the program. But the performance of Pi 3B is limited, if the resolution is above 640x368@15fps the HW encoder will be unstable, stuck, or even crash.Set pi_webrtc
to run as a daemon.
/etc/systemd/system/webrtc.service
, config sample:
[Unit]
Description= the webrtc service need signaling server first
After=systemd-networkd.service farmer-api.service
[Service]
Type=simple
WorkingDirectory=/home/pi/IoT/RaspberryPi_WebRTC/build
ExecStartPre=/bin/sleep 60
ExecStart=/home/pi/IoT/RaspberryPi_WebRTC/build/pi_webrtc --fps=30 --width=1280 --height=720 --v4l2_format=h264 --enable_v4l2_dma --mqtt_username=hakunamatata --mqtt_password=wonderful --record_path=/home/pi/video/
Restart=always
RestartSec=20
[Install]
WantedBy=multi-user.target
sudo systemctl enable webrtc.service
sudo systemctl start webrtc.service
If the cellular network is used, the coturn
is required because the 5G NAT setting by ISP may block p2p.
sudo apt update
sudo apt install coturn
sudo systemctl stop coturn.service
sudo nano /etc/turnserver.conf
, uncomment or modify below options
listening-port=3478
listening-ip=192.168.x.x
relay-ip=192.168.x.x
external-ip=174.127.x.x/192.168.x.x
#verbose
lt-cred-mech
user=webrtc:webrtc
realm=greenhouse
no-tls
no-dtls
syslog
no-cli
3478
forwarding on the routersudo systemctl start coturn.service