index.js

const ffmpeg = require('fluent-ffmpeg');
const ffmpegInstaller = require('@ffmpeg-installer/ffmpeg');
ffmpeg.setFfmpegPath(ffmpegInstaller.path);
const fs = require('fs');
var filename = 'videos/input.mp4';

function callback() { // do something when encoding is done 
    fs.writeFile("videos/index.m3u8", '#EXTM3U\n#EXT-X-VERSION:3\n#EXT-X-STREAM-INF:BANDWIDTH=800000,RESOLUTION=640x360\n360p.m3u8\n#EXT-X-STREAM-INF:BANDWIDTH=1400000,RESOLUTION=842x480\n480p.m3u8\n#EXT-X-STREAM-INF:BANDWIDTH=2800000,RESOLUTION=1280x720\n720p.m3u8', function (err) {
        if (err) {
            return console.log(err);
        }
        console.log("The file was saved!");
    })
}


ffmpeg(filename).addOptions([ //360
    '-profile:v main',
    '-vf scale=w=640:h=360:force_original_aspect_ratio=decrease',
    '-c:a aac',
    '-ar 48000',
    '-b:a 96k',
    '-c:v h264',
    '-crf 20',
    '-g 48',
    '-keyint_min 48',
    '-sc_threshold 0',
    '-b:v 800k',
    '-maxrate 856k',
    '-bufsize 1200k',
    '-hls_time 10',
    '-hls_segment_filename videos/360p_%03d.ts',
    '-hls_playlist_type vod',
    '-f hls'
]).output('videos/360p.m3u8').run()

ffmpeg(filename).addOptions([ //480
    '-profile:v main',
    '-vf scale=w=842:h=480:force_original_aspect_ratio=decrease',
    '-c:a aac',
    '-ar 48000',
    '-b:a 128k',
    '-c:v h264',
    '-crf 20',
    '-g 48',
    '-keyint_min 48',
    '-sc_threshold 0',
    '-b:v 1400k',
    '-maxrate 1498k',
    '-bufsize 2100k',
    '-hls_time 10',
    '-hls_segment_filename videos/480p_%03d.ts',
    '-hls_playlist_type vod',
    '-f hls'
]).output('videos/480p.m3u8').run()

ffmpeg(filename).addOptions([ //720
    '-profile:v main',
    '-vf scale=w=1280:h=720:force_original_aspect_ratio=decrease',
    '-c:a aac',
    '-ar 48000',
    '-b:a 128k',
    '-c:v h264',
    '-crf 20',
    '-g 48',
    '-keyint_min 48',
    '-sc_threshold 0',
    '-b:v 2800k',
    '-maxrate 2996k',
    '-bufsize 4200k',
    '-hls_time 10', 
    '-hls_segment_filename videos/720p_%03d.ts',
    '-hls_playlist_type vod',
    '-f hls' 
]).output('videos/720p.m3u8').on('end', callback).run()