The display program of ImageMagick is useful when you are at the shell and need to quickly view one or a few images. It can also be used to apply many of the image processing operations available in ImageMagick on an image and view it. This viewer is extremely light and great for checking some images quickly on a remote computer over SSH.
$ sudo apt install imagemagick
$ display foo.jpg
$ display *.jpg
$ display *
$ display -immutable *.jpg
F1 to view help about the mouse operations and keyboard operations available in this program.
Some of the keyboard shortcuts I frequently use:
Space: Next image Backspace: Previous image Esc: Quit /: Rotate by 90 degrees <: Zoom out >: Zoom in
Tried with: ImageMagick 188.8.131.52 and Ubuntu 16.04