Given a directory containing:
.
├── LRT_00001.jpg
├── LRT_00002.jpg
├── LRT_00003.jpg
├── LRT_00004.jpg
├── LRT_00005.jpg
├── ...
run the following:
ffmpeg -r 23.976 -start_number 00001 -i LRT_%5d.jpg -s 3840×2160 -vcodec libx264 sunset.mp4
^ frame rate ^ resolution