This repository contains info & bash scripts to create a YouTube live stream from a raspberry pi camera module.
The setup provides that two raspberry pis are used to create the stream: One which captures the video and another one which transforms the captured video into a format that can be streamed on YouTube.
A YouTube channel activated for streaming needs to be present before proceeding. Activation takes more than 24 hours.
Start a capture on the capture device by running capture-device-run.sh. Set up the transformer by running transformer-setup.sh. Set up the stream by running stream-setup.sh. Start streaming by running transformer-run.sh or better yet create a cron job that runs transformer-run.sh every minute. See below for requirements.
If you create a live broadcast that is longer than 12 hours, the recording of the broadcast will not be saved. You will see the broadcast in the list of your live broadcasts, but will not be able to watch or edit it. To remedy this limitation, you can add a cronjob that runs on specific hours, say every 8 hours, which executes the broadcast-complete-current-start-new.sh script. This script uses the variables that have been set before to complete the currently running live broadcast and start a new one that will get bound to the livestream that is still active. This script also adds the newly created livebroadcast to a playlist. The playlist properties are defined during the stream setup.
It is possible to dynamically change the title of the livebroadcast by using the "$youtubeApiClientPath/client-variables.sh" -t "New title with $variable" "$youtubeApiClientPath/client-variables.sh" parameters in the broadcast-complete-current-start-new.sh script.
The script get-number-of-days-since-start-of-stream.sh can be used to construct the dynamic title.
The capture device uses v4l2rtspserver to create an rtsp stream. v4l2rtspserver does not support
the new unicam interface provided by debian bullseye. Therefore,
the legacy camera interface needs to be enabled with raspi-config.
This provides the bcm2835-v4l2 interface which is compatible with the rtspserver. v4l2-ctl --list-devices can be used to see the interfaces available.
v4l2rtspserver needs to be compiled from source. It is enough to run
sudo apt install git cmake
git clone https://github.com/mpromonet/v4l2rtspserver.git
cd v4l2rtspserver
cmake . && make && sudo make install
on the capture device. After successful compilation, the rtsp stream can be started by running the capture-device-run.sh script.
Adjustments to the video source can be made by invoking v4l2-ctl. Use v4l2-ctl -l to see
the adjustments supported by your camera.
To consume the stream, ffmpeg needs to be installed on the transformer. Use this command to transform
the rtsp stream into a rtmp stream and send it to YouTube:
ffmpeg -re -rtsp_transport tcp -i "rtsp://<capture_device_host>:<port>/unicast" \
-f lavfi -i anullsrc=channel_layout=stereo:sample_rate=44100 \
-c:a libmp3lame -ab 128k -ar 44100 \
-c:v copy -threads 2 -bufsize 512k \
-f flv "rtmp://a.rtmp.youtube.com/live2/<live-stream-key>"
The <live-stream-key> can be obtained by querying the YouTube data api.
To use the api, an access token is required. To request an access token, the Google auth endpoint needs to be called with the
appropriate scope, the client_id, the access_type parameter set to offline and the prompt parameter set to
consent. This will result in an authorization response that contains a refresh token which must be used to retrieve
subsequent access tokens.
To set up authentication, an application in the Google developer console needs to be created. The YouTube data api needs to be enabled and an oauth client desktop or web application needs to be created.
Using a desktop application credential configuration sets the redirect url to a static value, that is used for out of band authorization requests. This means that the authorization code has to be copied manually from the browser. This credential configuration is going to be deprecated by Google on October 3, 2022.
Using a web application credential configuration requires a https endpoint which can receive the authentication request redirected by Google. These scripts provide that endpoint if you have configured the domain and secured it via ssl. You need to provide the authentication url to this script, it should be in the form https://hostname.tld/oauth.html and must be the exact same string entered in the web application credential configuration in the Google developer console. To provide the https endpoint, the wait-for-authcode.sh script will configure socat to listen on port 443, it is therefore requiring sudo permissions. These permissions will be granted by toggle-socat-unprivileged-access-to-low-tcp-ports.sh, the permissions will be immediately revoked after the authentication redirect has been successfully received.
The last step is to create an OAuth consent screen.
To start a live stream, a livestream resource
needs to be inserted. The data is fed to the livestream with the ffmpeg command. To view the livestream
on YouTube, a livebroadcast resource needs to be created and bound to the livestream resource
via the livestream id. After the broadcast is successfully bound to the livestream, it needs to
be transitioned to the live status.
Livebroadcasts can be added to a playlist as a playlistItem.
This is happening for the most recent inserted broadcast in the broadcast-complete-current-start-new.sh script.
All the http requests are made with curl. Json parsing is done with jq. Jobs are controlled with screen.