ffmpeg -f v4l2 -framerate 30 -video_size 1280x720 -i /dev/video0 -c:v libx264 -preset veryfast -tune zerolatency -b:v 2M -bufsize 2M -maxrate 2M -g 60 -keyint_min 60 -sc_threshold 0 -f flv rtmp://your_streaming_server_address
ffmpeg -i /path/to/your/video.mp4 -c:v libx264 -preset veryfast -tune zerolatency -b:v 2M -bufsize 2M -maxrate 2M -g 60 -keyint_min 60 -sc_threshold 0 -f flv rtmp://your_streaming_server_address
