ffmpeg Unrecognized option 'tune' - node.js

Question

I'm using ffmpeg on node.js. And option '-tune zerolatency' for low latency
But when I insert "-tune zerolatency", I get an error: Unrecognized option 'tune'.
Can anyone help? I have no idea what to do.
Here's the script.
let token = '#!#!##%#$##%#^^!#$##$##$##$^##$'
let option = [
'-i', 'pipe:0', //mpeg4
'-acodec', 'copy',
'-vcodec', 'copy',
'-s', '284x164',
'-preset', 'ultrafast',
'-tune', 'zerolatency',
'-f', 'flv',
'rtmp://localhost:1935/s/' + token,
];
ffmpeg = spawn("ffmpeg", option);
ffmpeg.stdin.write(streaming_data);
Here's the ffmpeg version
ffmpeg version N-82166-g894e7ef Copyright (c) 2000-2016 the FFmpeg developers
built with gcc 4.8.3 (GCC) 20140911 (Red Hat 4.8.3-9)
configuration: --prefix=/usr/local/ffmpeg_build --extra-cflags=-I/usr/local/ffmpeg_build/include --extra-ldflags=-L/usr/local/ffmpeg_build/lib --bindir=/usr/local/bin
libavutil 55. 35.100 / 55. 35.100
libavcodec 57. 65.100 / 57. 65.100
libavformat 57. 57.100 / 57. 57.100
libavdevice 57. 2.100 / 57. 2.100
libavfilter 6. 66.100 / 6. 66.100
libswscale 4. 3.100 / 4. 3.100
libswresample 2. 4.100 / 2. 4.100

Answer 1

tune is a private option of certain encoders, not a common option. Since you are copying the video stream over, no encoder is invoked, and so the option isn't recognized. Similar is true of the size and preset options, although those are common options and they are simply inert instead of unknown in this command.
If you change '-vcodec', 'copy' to '-vcodec', 'libx264', all three options will take effect. But this will transcode the video, so time and CPU use will increase.