How to slow down ffmpeg encoding speed?

Question

fmpeg

Hello.
There is a FullHD mp4 file with a duration of 4 minutes, which must be transferred via rtmp.
If you run the command

ffmpeg -i test.mp4 -filter:v scale=426:240 -vcodec libx264 -preset ultrafast -r 24 -b:v 384k -bufsize 1500k -acodec copy -bsf:a aac_adtstoasc -f flv rtmp://localhost/hls240p

The file will be successfully transferred, but in 2-3 seconds. Can I stream at video playback speed?
You cannot change the input file and output stream to another one.
ffmpeg version N-71312-ga66dcfe Copyright (c) 2000-2015 the FFmpeg developers

Answer 1

add -re option before -i
https://trac.ffmpeg.org/wiki/StreamingGuide