Given directory $d where new images are being created, for displaying the images as they appear, starting from the freshest one, I'm using

feh -S mtime --reverse -D 1 -R 1 --on-last-slide hold --start-at $(ls -1tr "$d" | tail -n 1) "$d"

(I'm not sure how it performs for huge amount of images, as it is short-periodically reloading the list)

Given directory $d where new images are being created, for displaying the images as they appear, starting from the freshest one, I'm using

feh -S mtime --reverse -D 1 -R 1 --on-last-slide hold --start-at $(ls -1tr "$d" | tail -n 1) "$d"

(I'm not sure how it performs for huge amount of images, as it is short-periodically reloading the list)

Options used:

• -S mtime sorts images by their modification (creation) time
• --reverse reverses the sort order (as default is descending, for some reason)
• -D 1 slideshow delay 1 sec
• -R 1 regenerates image list every 1 sec
• --on-last-slide hold to stop on last image, not quit or restart
• --start-at $(ls -1tr "$d" | tail -n 1) starts the slideshow with the newest one