software for Mac like irfanview?

I need to stitch together vertically several jpgs. On my PC (which will be decommissioned as soon as my new iMac arrives) I use irfanview: I select Create Panorama Image and check Vertical. Then select my images, click Create Image, and I have a vertical jpg. I'd like to do this on my iMac and would appreciate your advice and suggestions. Thanks!

dmrowley said:

Take a look at Diptic on the Mac App Store

https://itunes.apple.com/us/app/diptic/id526546615?mt=12

Click to expand...

Thanks for the suggestion. I checked it out, and I don't think it will let me stitch a dozen jpgs vertically. It seems to have preformed templates, which don't appear to do what I need. If I missed something, please let me know.