FastCRC Library

From SlavaSoft:

A fast, highly optimized implementation of popular checksum algorithms: CRC32, CRC16, CRC16C (CRC-CCITT). The library allows to calculate checksums for files, memory blocks, strings, blobs, streaming data. It is quick, flexible, easy to use. It supports 3 interfaces: FastCRC API (the API can be used as is, or it can be used to create wrappers for languages that can use DLL or LIB), C++ Interface (C++ wrapper classes to FastCRC API), and FastCRC Type Library (includes all declarations for accessing the functionality from programming languages that can reference a .TLB, such as VB 5.0, VB 6.0, VBA, etc). It allows static/dynamic linking. It has no external dependencies such as MFC DLLs, COM/DCOM or other component. The help file has C, C++ and Visual Basic examples showing how to add checksum calculations to Windows applications quickly and easily.