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/* 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.
*/
#ifndef RS_H
#define RS_H
#define MM 12 /* RS code over GF(2**MM) - change to suit */
//#define KK 4015 /* 223 */ /* KK = number of information symbols */
#define NN ((1 << MM) - 1)
#if (MM <= 8)
typedef unsigned char dtype;
#else
typedef unsigned int dtype;
#endif
/* 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 rs_encode (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 rs_eras_dec (dtype data[], int eras_pos[], int no_eras);
/* buf_len is the constraining factor here */
void
rs_trans (unsigned char *buffer, unsigned long int buf_len,
unsigned int *trans, unsigned long int trans_len);
/* here it is trans_len ! */
void
rs_detrans (unsigned char *buffer, unsigned long int buf_len,
unsigned int *trans, unsigned long int trans_len);
#endif
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