Drempels alternative?

Has anyone ever used drempels before? (URL = https://sourceforge.net/projects/drempels/)

I've recently used Drempels but was disappointed at it. It appears to resample the images provided at a ridiculously low resolution. Images with lots of detail look like pixellated messes. Anyone know a program that does something similar to drempels but a little better perhaps?

The reason it's resampled so badly is for speed.

Do you really want your background hogging the CPU?