I have a set of images - a pack of cards - which are too big. Is there any way I could resize them all at once?
Just use photoshop, and the batch option, I use this method all the time.. Make an action.. Then run a batch using this action and everything will automatically run. If you want just send me the file, and I'll do it for you..
assuming that you have photoshop, it has a great batch option. just record one resize in the actions palette and you'll be set from there. choose your folder and the target directory, choose your action and let it go. best of luck to ya.