raspberry pi – YUYV/MJPEG format converision to v4l2rtspserver compatible format

I have a camera that supports YUYV or MJPG and i want to use that camera to be streamed through a v4l2rtspserver which doesnt support these formats. I have ressources limitations so i want the best approach to convert the camera feed contuniously. What could be the best approach? are there reliable alternatives to use other than v4l2rtspserver that support these formats directly?

I tried ffmpeg conversion but i have my concerns about the amount of ressources it uses and i want the see what could be the best approache.