Sometimes I use XnView's* "batch conversion" tool to downsize a bunch of JPEGs (to maximum of 1600x1200). But some of them are equal or smaller than that and no resizing is done.
Is any image quality lost during the process? (Even if I choose JPEG 100% quality?)
Edit: I was asking about those images which are already smaller than the limit, and are not being resized, just re-compressed.
* My Linux laptop is toast, can't do any imagemagick tricks.