fec.h

#ifndef __DSD_FEC_H__
#define __DSD_FEC_H__

/* RS code over GF(2**mm) */
/* nn=2**mm-1 -> length of codeword */
#define MAX_NN 255
#define MAX_TT 8
#define NN ((1<<MM)-1)

typedef struct _ReedSolomon {
    int alpha_to[MAX_NN + 1];
    int index_of[MAX_NN + 1];
    int gg[17];
    /* tt -> number of errors that can be corrected */
    unsigned char tt;
    /* distance = nn-kk+1 = 2*tt+1 */
    unsigned int n;
} ReedSolomon;

unsigned char Hamming7_4_Correct(unsigned char value);
void Hamming15_11_3_Correct(unsigned int *block);
void p25_Hamming10_6_4_Correct(unsigned int *codeword);
void p25_Hamming15_11_3_Correct(unsigned int *codeword);
void p25_lsd_cyclic1685_Correct(unsigned int *codeword);
unsigned int p25_trellis_1_2_decode(unsigned char *in, unsigned int in_sz, unsigned char *out);
void Golay23_Correct(unsigned int *block);

unsigned char Hamming7_4_Encode(unsigned char value);
unsigned int Hamming15_11_3_Encode(unsigned int input);
unsigned int p25_Hamming10_6_4_Encode(unsigned int input);
unsigned int p25_Hamming15_11_3_Encode(unsigned int input);
unsigned int p25_lsd_cyclic1685_Encode(unsigned int input);
void p25_trellis_1_2_encode(unsigned char *data_in, unsigned int data_len, unsigned char *out);
unsigned int Golay23_Encode(unsigned int cw);

void rs8_init(ReedSolomon *rs, unsigned int generator_polinomial, unsigned char tt);
void rs8_encode(ReedSolomon *rs, const unsigned char *data, unsigned char *bb);
int rs8_decode(ReedSolomon *rs, unsigned char *input, unsigned char *output);
void rs6_init(ReedSolomon *rs, unsigned int generator_polinomial, unsigned char tt);
void rs6_encode(ReedSolomon *rs, const unsigned char *data, unsigned char *bb);
int rs6_decode(ReedSolomon *rs, unsigned char *input, unsigned char *output);

#endif