ffmpeg create looped slideshow over a music track.

imgseq.sh

#!/bin/bash

# folder wth images
IMAGE_DIRECTORY="test_footage"

# image extension
IMAGE_EXT="jpg"

#SLIDE TIME IN SECONDS
SLIDE_DURATION=2

#audio track file
AUDIO="test_footage/music.mp3"

#output file
LOOP_FILE="loop.mp4"
OUT="out.mp4"

FR=$(awk "BEGIN {print 1/$SLIDE_DURATION}")

ffmpeg -y -framerate $FR -pattern_type glob -i "$IMAGE_DIRECTORY/*.$IMAGE_EXT" -vf "pad=ceil(iw/2)*2:ceil(ih/2)*2" -q:v 2 $LOOP_FILE
ffmpeg -stream_loop -1 -i $LOOP_FILE -c copy -v 0 -f nut - | ffmpeg -y -thread_queue_size 10K -i - -i $AUDIO -c copy -map 0:v -map 1:a -shortest $OUT
rm $LOOP_FILE