GNU Radio 2.x: int.h Source File

00001 /* Include file to configure the RS codec for integer symbols
00002  *
00003  * Copyright 2002, Phil Karn, KA9Q
00004  * May be used under the terms of the GNU General Public License (GPL)
00005  */
00006 #define DTYPE int
00007 
00008 /* Reed-Solomon codec control block */
00009 struct rs {
00010   unsigned int mm;   /* Bits per symbol */
00011   unsigned int nn;   /* Symbols per block (= (1<<mm)-1) */
00012   int *alpha_to;      /* log lookup table */
00013   int *index_of;      /* Antilog lookup table */
00014   int *genpoly;       /* Generator polynomial */
00015   unsigned int nroots;     /* Number of generator roots = number of parity symbols */
00016   unsigned int fcr;        /* First consecutive root, index form */
00017   unsigned int prim;       /* Primitive element, index form */
00018   unsigned int iprim;      /* prim-th root of 1, index form */
00019 };
00020 
00021 static inline int modnn(struct rs *rs,int x){
00022   while (x >= rs->nn) {
00023     x -= rs->nn;
00024     x = (x >> rs->mm) + (x & rs->nn);
00025   }
00026   return x;
00027 }
00028 #define MODNN(x) modnn(rs,x)
00029 
00030 #define MM (rs->mm)
00031 #define NN (rs->nn)
00032 #define ALPHA_TO (rs->alpha_to) 
00033 #define INDEX_OF (rs->index_of)
00034 #define GENPOLY (rs->genpoly)
00035 #define NROOTS (rs->nroots)
00036 #define FCR (rs->fcr)
00037 #define PRIM (rs->prim)
00038 #define IPRIM (rs->iprim)
00039 #define A0 (NN)
00040 
00041 #define ENCODE_RS encode_rs_int
00042 #define DECODE_RS decode_rs_int
00043 #define INIT_RS init_rs_int
00044 #define FREE_RS free_rs_int
00045 
00046 void ENCODE_RS(void *p,DTYPE *data,DTYPE *parity);
00047 int DECODE_RS(void *p,DTYPE *data,int *eras_pos,int no_eras);
00048 void *INIT_RS(unsigned int symsize,unsigned int gfpoly,unsigned int fcr,
00049                    unsigned int prim,unsigned int nroots);
00050 void FREE_RS(void *p);
00051 
00052 
00053 
00054