Chord Image Generator
Chord Image Generator is a small .NET library to generate images of guitar chords. It can display chord boxes, starting frets, barred chords, fingerings and open and muted strings.
There is a small example website at http://chordgenerator.net where you can try different chords and see how they are constructed. But basically it is just done by constructing the right url of the form /chordname/fret-positions/fingerings/size . E.g. the chords above are the following urls:
There is nothing web specific about the actual image generation. It can be saved to any stream so you could just as easily use it in a desktop application.
The source is licensed under the GPL. You are also free to link directly to chordgenerator.net, although I give no guarantees about uptime or reliability.