/*
* Copyright (c) 2001-2003, David Janssens
* Copyright (c) 2002-2003, Yannick Verschueren
* Copyright (c) 2003-2005, Francois Devaux and Antonin Descampe
* Copyright (c) 2005, Hervé Drolon, FreeImage Team
* Copyright (c) 2002-2005, Communications and remote sensing Laboratory, Universite catholique de Louvain, Belgium
* Copyright (c) 2005-2006, Dept. of Electronic and Information Engineering, Universita' degli Studi di Perugia, Italy
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS `AS IS'
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#ifdef USE_JPWL
/**
@file rs.h
@brief Functions used to compute Reed-Solomon parity and check of byte arrays
*/
#ifndef __RS_HEADER__
#define __RS_HEADER__
/** Global definitions for Reed-Solomon encoder/decoder
* Phil Karn KA9Q, September 1996
*
* The parameters MM and KK specify the Reed-Solomon code parameters.
*
* Set MM to be the size of each code symbol in bits. The Reed-Solomon
* block size will then be NN = 2**M - 1 symbols. Supported values are
* defined in rs.c.
*
* Set KK to be the number of data symbols in each block, which must be
* less than the block size. The code will then be able to correct up
* to NN-KK erasures or (NN-KK)/2 errors, or combinations thereof with
* each error counting as two erasures.
*/
#define MM 8 /* RS code over GF(2**MM) - change to suit */
//static int KK;
int KK;
/* Original code */
/*#define KK 239*/ /* KK = number of information symbols */
#define NN ((1 << MM) - 1)
#if (MM <= 8)
typedef unsigned char dtype;
#else
typedef unsigned int dtype;
#endif
/** Initialization function */
void init_rs(int);
/** These two functions *must* be called in this order (e.g.,
* by init_rs()) before any encoding/decoding
*/
void generate_gf(void); /* Generate Galois Field */
void gen_poly(void); /* Generate generator polynomial */
/** Reed-Solomon encoding
* data[] is the input block, parity symbols are placed in bb[]
* bb[] may lie past the end of the data, e.g., for (255,223):
* encode_rs(&data[0],&data[223]);
*/
int encode_rs(dtype data[], dtype bb[]);
/** Reed-Solomon erasures-and-errors decoding
* The received block goes into data[], and a list of zero-origin
* erasure positions, if any, goes in eras_pos[] with a count in no_eras.
*
* The decoder corrects the symbols in place, if possible and returns
* the number of corrected symbols. If the codeword is illegal or
* uncorrectible, the data array is unchanged and -1 is returned
*/
int eras_dec_rs(dtype data[], int eras_pos[], int no_eras);
/**
Computes the minimum between two integers
@param a first integer to compare
@param b second integer to compare
@return returns the minimum integer between a and b
*/
#ifndef min
#define min(a,b) (((a) < (b)) ? (a) : (b))
#endif /* min */
#endif /* __RS_HEADER__ */
#endif /* USE_JPWL */