librs is a small library for forward error correction with Reed-Solomon codes. It is based on the Reed-Solomon code in Phil Karn's libfec, but with bugfixes, optimizations and a slightly different interface. The encoder and decoder are general purpose and not optimized for any particular code. The main use case is for simulations with Reed-Solomon codes.

If you need a Reed-Solomon library for production use that is optimized for one specific code, then the various C++ template libraries might be faster and/or better suited for that particular application.

INSTALLATION

If installing from a release tarball, the standard

./configure
make
make install

will suffice. If you're building from git then run

autoreconf -i --force
./configure
make
make install

USAGE

In short

    struct rs_code* rs;

    // init Reed-Solomon code
    rs = rs_init(symsize, gfpoly, fcr, prim, nroots);
    if (!rs)
	    // Handle error!

    /* Encode your data. The data buffer must contain enough space for the
     * parity symbols. More specifically, len = 'length of data' + nroots. */
    rs_encode(rs, data, len, stride);

    // Possible data corruption...

    // Correct errors (no erasures)
    int ret_val = rs_decode(rs, data, len, stride, NULL, 0, NULL);
    if (ret_val < 0)
	// decoding failure, handle appropriately

    // Free resources
    rs_free(rs);

See the man page for more information.

NOTES

The Reed-Solomon encoding used by the library is the BCH view, and the encoding is systematic. For more information, see, for instance, Wikipedia.