After checking the "Don not enlarge", if the width and height you write bigger than the original number, the aim photos won't be resized, they reserve the original size. On the contrary, you can resize them at the self-defined size.
Operation refers to steps below:
Add photos;
Base on need, select a mode from "Type" box and then check the checkbox "Do not enlarge";
On the bottom menu line select one format from the selection box;
Click button "Convert".
PS: Boxoft Batch Photo Resizer provides 9 output formats: tif, gif, bmp, png, jpg, pcx, j2k, tga and ico. So not only is it a resizer, but also a converter!