select multiple images and export multiple images

[orlf]

Hello,

I want to reverse colors of a lot of images, but I don't know how (if it's possible) to do that in all the images in one time. Currently I do one image by one image and it takes a lot of time.

Same for exporting images, I don't know how to export all the images wich are opened in gimp in one time.

I hope somebody know how to do.