I want some projects ideas of medium complex projects related to graphics, can be developed in C# .Net?

Answer 1

I've done a lot of work in this area. You could make a web application that overlays text onto a bitmap using the System.Drawing.Graphics class. Or you could write a program to parse and render scalable vector graphics ( http://www.w3.org/Graphics/SVG/ )

You could OLE automate a graphics program, like Adobe InDesign, too.

Answer 2

I once created one that scanned paperwork from scanners, and auto cropped them.

The auto cropping was a challenge.

Answer 3

Some fine examples can be found here: http://www.google.com/puzzles/.