XnView Software

Convert->Batch Processing->Transformations->Canvas resize->Parameters->"add resize by bigger or smaller side"

I have a lot of big photos(19-20Mb, with huge resolution). I need convert them to smaller size for example 1024*768. But some photos have resolution for example 3744*5616, others 5616*3744, so when I convert them all I have same resolution 1024*768, but I need 3744*5616->768*1024 and 5616*3744->1024*768.

I think it's already there: In resize dialog, specify 1024 x 1024 as width and height. Make sure that "Keep ratio" checkbox is checked. Then start your batch conversion. XnView will resize your images to a maximum width of 1024 and a maximum width of 1024.

No, I think it's a case like this:
I have 2:3 and 2:1 pics. I want to size by smaller edge. So instead of getting output like
200x300 and 150x300
I'd get
200x300 and 200x400

This makes more sense instead of making panoramas tiny.