What I have is a folder full of about 100 images of various sizes and shapes spread across various sub-folders. I need to blank out all these images ( or ideally replace them with some subtle pattern ) while keeping the pixel sizes, names and folder structure. Is there any software that anyone knows of that can batch process in any way similar to this.
Well, as far as my knowledge is concerned, you can do this using Photoshop Actions (or preferably saying, that's what I would have done). Photoshop Actions are basically a series of, well actions (I don't find any other word), that you can record as a macro and repeat as many times as needed with a single click.
The following link quite well elaborates on creating and using Photoshop Actions: