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Diffstat (limited to 'src/fec/rs-common.h')
-rw-r--r-- | src/fec/rs-common.h | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/src/fec/rs-common.h b/src/fec/rs-common.h new file mode 100644 index 0000000..e64eb39 --- /dev/null +++ b/src/fec/rs-common.h @@ -0,0 +1,26 @@ +/* Stuff common to all the general-purpose Reed-Solomon codecs + * Copyright 2004 Phil Karn, KA9Q + * May be used under the terms of the GNU Lesser General Public License (LGPL) + */ + +/* Reed-Solomon codec control block */ +struct rs { + int mm; /* Bits per symbol */ + int nn; /* Symbols per block (= (1<<mm)-1) */ + data_t *alpha_to; /* log lookup table */ + data_t *index_of; /* Antilog lookup table */ + data_t *genpoly; /* Generator polynomial */ + int nroots; /* Number of generator roots = number of parity symbols */ + int fcr; /* First consecutive root, index form */ + int prim; /* Primitive element, index form */ + int iprim; /* prim-th root of 1, index form */ + int pad; /* Padding bytes in shortened block */ +}; + +static inline int modnn(struct rs *rs,int x){ + while (x >= rs->nn) { + x -= rs->nn; + x = (x >> rs->mm) + (x & rs->nn); + } + return x; +} |