sPhoto is a very simple open-source application for bulk (batch) photo editing.
If you have hundreds of photos you can easily resize, rename, or even add watermarks to them all. Every change you make you will be able to see in the preview window.
The software is very easy and intuitive. You can crop or rotate any single photo.
And when you click start the software immediately converts all of your photos just as you viewed them in the preview. When the work is completed you can see the results and also save the settings as a preset for the next batch of photos to make editing photos extremely easy.