How to stream WebCam stream in OGG format with VLC over HTTP

streaming_webcam_ogg_with_vlc_over_http.md

VLC command:

vlc v4l2:// :input-slave=alsa:// :v4l2-standard=1 :v4l2-dev=/dev/video0 :v4l2-width=1280 :v4l2-height=720 :sout="#transcode{vcodec=theo,vb=2000,acodec=vorb,ab=128,channels=2,samplerate=44100}:http{dst=:8081/webcam.ogg}" -I dummy

Source: https://bioinfoexpert.com/blog/2016/08/09/stream-audio-video-from-webcam-using-vlc/

Works also on Raspberry Pi's w/ Ubuntu, but it seems that a Pi-specific VLC distribution is needed, i.e.:

sudo apt-get install -y v4l-utils
sudo snap install --edge --devmode vlc-pi
sudo usermod -a -G video $USER
vlc-pi v4l2:// :v4l2-standard=1 :v4l2-dev=/dev/video0 :v4l2-width=640 :v4l2-height=480 :sout="#transcode{vcodec=theo,vb=64,acodec=vorb,ab=64,channels=2,samplerate=44100}:http{dst=:8081/webcam.ogg}" -I dummy 

Note: Audio device didn't seem to work though

One can also take screenshots of the stream by running:

vlc http://localhost:8081/webcam.ogg --rate=1 --video-filter=scene --vout=dummy --aout=dummy --scene-format=png --scene-ratio=24 --scene-prefix=snap --scene-path=/tmp/ vlc://quit

Note: You have to manually kill this process afterwards to make it stop, because --start-time=10 --stop-time=11 (which is typically used for video stream length limiting) is meant for static videos not live streams.