You can use Light Image Resizer from command line, so you can call it from anything like a batch script, .NET, C#, CSharp, CGI, Visual Basic, or Delphi

Feel free to ask any question about licensing or suggest any addition.
Basically, you can find also all the options of Light Image Resizer in the registry, so you can easily program it the way you need it for your project.

Command Line Reference for Light Image Resizer: