Open Photoshop, hit command-N (for new file), make it 11 by 8.5 inches, grayscale, 150 to 300 dpi resolution, hit OK. Then go to "File", choose "place" and in the dialog box choose a file from your archive. Hit "Open". The scan will now be placed as a layer into your new file window in Photoshop. Double click on it to place and make the grid disappear. Now go to "layers" and choose "Flatten image". You now have your scan in Photoshop that can be edited. You can just wipe out names using brush tool with white color and then add a text box and type a new name. Then hit "Save" and you can choose any format you want including pdf again.
Ok so when we were teenagers me and my best friend wrote each other lots of letters. I am now involved in a project where I need to scan in the handwritten letters, and then anonymize them somehow. I scan them in as pdfs. I need to be able to blur out names and then replace them with code names. It doesn't matter if it doesn't look that great, just so long as I can quickly and easy cover over the names and then write something on the top. Has anyone got any idea of any software I could use to do this?