IMGVerify

ImgVerify is a free open source .NET class for performing Image Verification. ImgVerify uses a number of techniques to attempt to prevent automated systems from interpreting the characters displayed in the image. Image names are seeded hashes with default master seeds as well as user chosen seeds for passing random characters or your own secret seed. Random characters can either be uppercase, lowercase or mixed case for increased security. The horizontal position of characters are random (helps prevent character recognition). Characters are italic, to provide a slope (helps prevent character recognition). Random lines cross the image (helps prevent character recognition).

Requirements:

Windows 2000/XP/2003 Server