[MN-dev] [mndiff]: r128 - in trunk/noe: ldpc.c ldpc.h test_ldpc.c

[michael]

Author: michael
Date: Wed Nov 26 00:01:45 2008
New Revision: 128

Log:
Make the sparseness of the parity matrix a user parameter.


Modified:
   trunk/noe/ldpc.c
   trunk/noe/ldpc.h
   trunk/noe/test_ldpc.c

Modified: trunk/noe/ldpc.c
==============================================================================
--- trunk/noe/ldpc.c	(original)
+++ trunk/noe/ldpc.c	Wed Nov 26 00:01:45 2008
@@ -73,22 +73,23 @@ int inverse(ELEM *matrix, int width, int
     return p;
 }
 
-LDPCContext *EXT(initLDPC)(int data_len, int parity_len, uint32_t seed){
+LDPCContext *EXT(initLDPC)(int data_len, int parity_len, uint32_t seed, int nzc){
     LDPCContext *c= malloc(sizeof(LDPCContext));
     int row[parity_len];
     KISSState kiss;
-    int i, j, y, nzc;
+    int i, j, y;
     int code_len= data_len + parity_len;
 
+    if(nzc==0){
     if     (parity_len < 16) nzc=3;
     else if(parity_len < 32) nzc=4;
     else if(parity_len < 64) nzc=5;
     else if(parity_len <256) nzc=6;
     else                     nzc=7;
+    }
 
-    if(nzc > MAX_NZC)
+    if(nzc > MAX_NZC || nzc > parity_len)
         goto fail;
-    assert(nzc <= parity_len);
 
     init_random(&kiss, seed);
 

Modified: trunk/noe/ldpc.h
==============================================================================
--- trunk/noe/ldpc.h	(original)
+++ trunk/noe/ldpc.h	Wed Nov 26 00:01:45 2008
@@ -18,7 +18,11 @@
 
 struct LDPCContext;
 
-struct LDPCContext *EXT(initLDPC)(int data_len, int parity_len, uint32_t seed);
+/**
+ *
+ * @param nzc number of non zero elements per column, 0 means choose automatically.
+ */
+struct LDPCContext *EXT(initLDPC)(int data_len, int parity_len, uint32_t seed, int nzc);
 
 /**
  *

Modified: trunk/noe/test_ldpc.c
==============================================================================
--- trunk/noe/test_ldpc.c	(original)
+++ trunk/noe/test_ldpc.c	Wed Nov 26 00:01:45 2008
@@ -49,13 +49,13 @@ int main(){
                 parity_pos[i]= data_len + i;
 
             for(seed=0; 1; seed++){
-                enc= EXT(initLDPC)(data_len, parity_len, seed);
+                enc= EXT(initLDPC)(data_len, parity_len, seed, 0);
                 if(EXT(init_matrixLDPC)(enc, parity_len, parity_pos) >= 0)
                     break;
                 EXT(freeLDPC)(enc);
             }
 
-            dec= EXT(initLDPC)(data_len, parity_len, seed);
+            dec= EXT(initLDPC)(data_len, parity_len, seed, 0);
 
             for(erasure_count= parity_len; erasure_count > parity_len-3; erasure_count--){
                 int fail=0;