CRC
PNG Cyclic Redundancy Checksum

CRC is a library of C++ routines that compute 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.

Reference:

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

Source Code:

• crc.C, the source code;
• crc.H, the include file;
• crc.csh, commands to compile the source code;

Examples and Tests:

• crc_prb.C, the calling program;
• crc_prb.csh, commands to compile, link and run the calling program;
• crc_prb_output.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.