Not sure where to put this thread, but it's kind of a technical issue, just not hardware.

A little while ago I made a lot of scans with XSane on Ubuntu. I noticed that whenever you saved a file it would say .jpg or .png at the end (not just on the properties menu). This never happened in Windows Explorer, where it would just show the photo name and not the extension (I only recently changed to Ubuntu), so I proceeded to remove the extensions from the photo names. The photos are still viewable, as Ubuntu knows they are JPEGs, but whenever I try to upload the files to a website, the websites can't tell that they are images.

So I need to find a way to fix this. If there was some program that let you change the file extensions of hundreds of images all at once, that would be cool. I just don't know of any programs like this. Hopefully I don't have to go into each filename and change the extension, cause you know, hundreds of files.