most image processing softwares can do that.
Just click on "text", then you can choose font,size,color of the text.
For large number of pictures, I use "image optimizer" to do
the resize, caption. It's easy to find it on web.
If you are using Photoshop for post processing and interested in adding watermark to the photos, let me know. I can email you an action I downloaded from dpreview which add watermark to the photos. Just leave your email address.
