Filenames renaming back to original

I just used the CVS Exporter to obtain my item records, but just remembered that Omeka renames file names. I would perform the matches between item records and filenames manually, but I have 12K+ records. Is there a way to figure out the original name of:


all my files have been renamed in:

I noticed when I am in admin, that I can see the original filename if I perform a mouseover:

So how do I extract that info? Because it is not in the cvs that the CVS exporter generates.