XnView Software

Hmm, I'm a bit confused! does this mean that somehow XnConvert is less effective than XnView? (unfortunately I use linux so I can't use the classic XnView)

(ty for the links)

Thank you for the answers!

I left the "Format" at "as original". If I change it now to PNG, the compression level is at 6. It looks like even if I change the compression level to 9 it is only a small change in file size.

However, that color depth change makes a huge impact. This is a great trick ...

Why do I get a bigger file size after decreasing the image size?

This is the base file:
http://s23.postimg.org/chc1had17/from.png
its size is 100.2 kB
after the resize: 179.8 kB
resample: lanczos

if I choose the "nearest neighbour" resample option, then the file size is smaller, but there is a ...