#!/bin/sh 
#ffmpeg  -y -r 1/5 -f concat -safe 0 -i list.txt -c:v libx264 -vf "fps=25,scale=1920:1080,format=yuv420p" out.mp4

ffmpeg -framerate 1.5/1 -i %04d.jpg -r 30 -vf "scale=1920:1080:force_original_aspect_ratio=decrease,pad=1920:1080:(ow-iw)/2:(oh-ih)/2,format=yuv420p" -codec:v libx264 -y out.mp4