Pregenerate thumbnails/previews of images?

[piphil]

Not sure where this belongs, but I'm a newbie so I guess here is a good place to start.

I'm processing large numbers of png images. When I browse the images, it's very useful to have the image icon thumbnails, but they are generated when I first open the folder. This can take some time.

Is there a way to pre-generate these thumbnails via the terminal or gui, other than opening all the relevant folders and leaving the PC overnight?

Any help appreciated!