Viewing Images with feh
I don't know how many Linux utilities exist for viewing graphics. Most distributions come with one, and usually that app is more than enough for you to flip through the images on your computer.
One image viewer I've been partial to for a while is feh. It a small, light image viewing tool that's simple to use. While you can run feh from a window manager, you can also run it from the command line.
To do the latter, open a open a terminal window and navigate to the folder containing the image or images that you want to view. Then, type:
A new window opens, displaying the image.
feh opens the image at or near its full size. You can scale the image by pressing the down arrow key on your keyboard.
To view multiple files, include a wildcard with the command — for example:
feh displays all the files with that extension. Click the window or press the left and right arrow keys on your keyboard to move between the images. feh also displays the number of images in the folder in its title bar.
While feh can't edit or save files to different formats, it's a great tool for quickly viewing graphics or photos and for creating impromptu slide shows.