This simple script lets you stream live from your RaspberryPi 3 (or higher) with RaspberryPi camera module to Google Youtube livestream.
CPU load of the ffmpeg process is about 30%. H264 complession is done in hardware, so ffmpeg only has to generate pts (timecode) and multiplex (zero audio and video) into flv stream
FullHD is possible. At least when the RaspberryPi is connected by ethernet cable.