bch15_5.h

00001 /*Copyright (C) 2008-2009  Timothy B. Terriberry (tterribe@xiph.org)
00002   You can redistribute this library and/or modify it under the terms of the
00003    GNU Lesser General Public License as published by the Free Software
00004    Foundation; either version 2.1 of the License, or (at your option) any later
00005    version.*/
00006 #if !defined(_bch15_5_H)
00007 # define _bch15_5_H (1)
00008 
00009 /*Encodes a raw 5-bit value _x into a 15-bit BCH(15,5) code.
00010   This is capable of correcting up to 3 bit errors, and detecting as many as
00011    5 bit errors in some cases.*/
00012 unsigned bch15_5_encode(unsigned _x);
00013 
00014 /*Corrects the received code *_y, if possible.
00015   The original data is located in the top five bits.
00016   Returns the number of errors corrected, or a negative value if decoding
00017    failed due to too many bit errors, in which case *_y is left unchanged.*/
00018 int bch15_5_correct(unsigned *_y);
00019 
00020 #endif
00021