It works quite simply: You take several pictures of the same location or the same monument. There is always one or more ugly tourists on the photo, but they are never in the same place. The software will identify the partly masked parts and fill them with data coming from images where they were not hidden by a tourist.
If you have enough pictures, if you work with a tripod (to ensure a good correspondence from image to image), it will “wipe” tourists out of the photo. It also works on passing cars or any other annoying mobile object that is tarnishing some of our photos. Technology at the service of solving a real problem.
Notice: This time, we are no longer on April Fools’ Day…