[nrapallo]

Originally Posted by carlb

IrfanView?

http://www.irfanview.com/

For such a large quantity of images, it may be easier to use http://www.imagemagick.org/script/convert.php as it can be run from a batch file to -resize or change colour -depth of large numbers of images at once.

Irfanview has a GUI interface that allows batch processing with many options. I'm using Windows and Irfanview is a workhorse that I've exploited countless times...

By the way, do you use Linux or did you compile the zimdump utility for Windows computers. I wouldn't mind having an executable copy of zimdump...