Based on the discovered information, the capture section of ffmpeg will look like :

ffmpeg \
        -f v4l2 -framerate 25 -video_size 960x540 -i /dev/video0
Check the supported video resolutions and frame rates :

ffmpeg  -hide_banner -f v4l2 -list_formats all -i /dev/video0
Find your capture card

v4l2-ctl --list-devices
or

v4l2-ctl --list-formats-ext
You can send your captured video to a multicast address, so that it can be viewed on many devices on your LAN. The advantage of multicast is that your encoder will only send the video stream once on the network, whatever the number of viewers you have.

ffmpeg \
        -f v4l2 -framerate 25 -video_size 960x540 -i /dev/video0 \
        -f alsa -ac 2 -i hw:CARD=HDMI,DEV=0 \
        -c:v libx264 -b:v 1600k -preset ultrafast \
        -x264opts keyint=50 -g 25 -pix_fmt yuv420p \
        -c:a aac -b:a 128k \
        -f rtp_mpegts rtp://239.0.0.2:5001?ttl=2
If you have a web server, you can send your captured video to it using ​HTTP Live Streaming (HLS) :

ffmpeg \
        -f v4l2 -framerate 25 -video_size 960x540 -i /dev/video0 \
        -f alsa -ac 2 -i hw:CARD=HDMI,DEV=0 \
        -c:v libx264 -b:v 1600k -preset ultrafast \
        -x264opts keyint=50 -g 25 -pix_fmt yuv420p \
        -c:a aac -b:a 128k \
        -f ssegment -segment_list playlist.m3u8 -segment_list_flags +live \
        -segment_time 10 out%03d.ts
Let's assume that we want to stream our webcam video + audio to our friends. We will simply run an ffmpeg command line that will capture our webcam video and audio input and forward it to ffserver. The command line will look something like this:

ffmpeg \
	-f v4l2 -s 320x240 -r 25 -i /dev/video0 \
	-f alsa -ac 1 -i hw:0 \
	http://localhost:8090/feed1.ffm

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