How to make icon file from pictures (jpg) in c++?

everyon my question is how to convert jpg to ico file, or how to make big icon with high resolution like in windows 7 icon, for example from games Purble place, that can be show at desktop开发者_运维百科 in big view?

Links from tutorials, examples and functions from c++ will be higly respect ..:)

If you insist on using some form of automation, then have a look at imagemagick --- it's a cross-platform command-line utility that can do file conversions and all sorts of cool image manipulation.