FFmpeg command for a looping MP4 set to a folder of MP3s for YouTube (HLS)

loop-hls.sh

# "FILENAME.mp4" is where your video filename goes
# "FOLDERNAME" is where your folder name goes for all your mp3s
# "STREAMKEYHLS" is where your stream key goes
#
# uses HLS instead of RTMP
#
# 960x720@30

#!/bin/bash

set -e

while true
do
  ffmpeg -loglevel info -y -re -stream_loop -1 \
  -i FILENAME.mp4 \
  -f concat -safe 0 -i <((for f in ./FOLDERNAME/*.mp3; do path="$PWD/$f"; echo "file ${path@Q}"; done) | shuf) \
  -c:v libx264 -preset veryfast -b:v 4000k -maxrate 4000k -bufsize 6000k \
  -vf scale=960:720 \
  -r 30 -g 60 -pix_fmt yuv420p \
  -c:a aac -b:a 128k -ar 44100 \
  -map 0:v:0 -map 1:a:0 \
  -hls_init_time 3 -hls_time 3 -master_pl_name master.m3u8 -http_persistent 1 -f hls -segment_wrap 1 -method POST "https://a.upload.youtube.com/http_upload_hls?cid=STREAMKEYHLS&copy=0&file=master.m3u8"
done