Picture The Batch

Recently, I helped my mama to resize her photos. I was wondering I could find the software which is able to batch resizing photos in Macintosh. As I knew an excellent viewing and processing photos tool in Windows which is the IrfanView. That one I like pretty much. I have never seen a good tool like that. Unfortunately, I’ve switched to be an Apple user for 1 year 6 months. So, I should find a good tool for batch resizing images. Finally, I found a nice tool which is “Picture The Batch”. It helps me a lot. But, it is a shareware. If someone could tell me the freeware tools, it’s appreciated.