CRC
PNG Cyclic Redundancy Checksum

CRC is a C++ library which computes the PNG CRC (cyclic redundancy checksum) for a string of bytes.

PNG is the Portable Network Graphics format. The PNG checksum algorithm is used as part of the encoding of a PNG file.

Languages:

CRC is available in a C++ version.

Related Data and Programs:

PNG, a data directory which contains examples of Portable Network Graphics (PNG) files, 2D graphics;

Reference:

1. World Wide Web Consortium,
   Portable Network Graphics (PNG) Specification,
   Second edition, 10 November 2003.

Source Code:

• crc.cpp, the source code;
• crc.hpp, the include file;

Examples and Tests:

• crc_test.cpp, the calling program;
• crc_test.txt, the sample output.

List of Routines:

• CRC returns the CRC of the bytes in BUF[0...LEN-1].
• MAKE_CRC_TABLE makes the table for a fast CRC computation.
• PRINT_CRC_TABLE prints the CRC table.
• TIMESTAMP prints the current YMDHMS date as a time stamp.
• UPDATE_CRC_C updates a running CRC with one more character.
• UPDATE_CRC_S updates a running CRC with a new string of characters.

You can go up one level to the C++ source codes.