Bringing back a month old thread, but I found this one today. Although I like irfanview which does really nice editing, it doesn't do circles. Chips are round.

"Paint.NET is free image and photo editing software for computers that run Windows. It features an intuitive and innovative user interface with support for layers, unlimited undo, special effects, and a wide variety of useful and powerful tools." There's also a support community so you can get help and find answers. The software comes from Microsoft. Yes, free from Microsoft?

http://www.getpaint.net/

I tried it on this chip scan, cropped to a circle, filled the background with white, rotated it and saved.

Free stuff is good!