How can I encode a string in base64 when using tail -f

I'm reading a log file with tail -f, filtering it with grep --line-buffered, parsing it with awk 'print $1 " " $2}' and in the end I want to base64 the result.

I know the pipe creates a stream and I can't just pass it to base64. I've played around with xargs but I didn't get it to work.

I kind of need to use the tail -f since I want it to react to every event. Any ideas?