Data Streams
Prerequisites
- A working PostmarketOS installation
- Have read through PostmarketOS General Tips
- Ability to login over
SSH
Project examples
Installation
A data stream server consists out of the webserver nginx and the nginx-mod-rtmp module. To eventually stream the data to our server, we use a command line utility for audio and video called ffmpeg
nginx
Start with updating and upgrading Alpine
sudo apk update && sudo apk upgrade -U
Followed by installing nginx
sudo apk add nginx
nginx-mod-rtmp
sudo apk add nginx-mod-rtmp
After installing the nginx-mod-rtmp we need to add a configuration block to the nginx configuration file that tells nginx where the stream will be available. Open the configuration file found at /etc/nginx/nginx.conf and add the following contents to the end of the file.
rtmp {
server {
listen 1935;
chunk_size 4096;
allow publish 127.0.0.1;
deny publish all;
application live {
live on;
record off;
}
}
}
PostmarketOS has a very strict firewall as stated in the PostmarketOS General Tips. If we want to eventually make our stream publicly accessible, we need to disable the firewall. Run the following command to temporary disable the firewall.
sudo rc-service nftables stop
When we reboot the phone, the firewall will be enabled again. So in order to completely disable the firewall you can run the following command
sudo rc-update del nftables
ffmpeg
To stream an audio or video file to our rtmp server, we need to install ffmpeg.
sudo apk add ffmpeg
After installing we are almost ready to start streaming
Usage
Uploading files
If you've followed along with installing PostmarketOS, you've enabled the SSH daemon. This also allows us to upload files to your phone over SFTP. Open your favorite (S)FTP client (ex.: filezilla) and enter the ip address and username of your PostmarketOS installation. An example:
server: 192.168.2.130 port: 22 username: user password: 147147
After connecting to your phone, you should be able to upload files. As an example, we're uploading a file named video.mp4 to the home folder of the user named user.
Streaming video files
ffmpeg -stream_loop -1 -re -i video.mp4 -c:v copy -f flv rtmp://localhost/live/stream