[Mndiff-dev] [mndiff]: r19 - trunk/mnzip/mnzip.c

[michael]

Author: michael
Date: Fri Jun 15 02:29:18 2007
New Revision: 19

Log:
remove RLE coder
slightly better compression and simpler


Modified:
   trunk/mnzip/mnzip.c

Modified: trunk/mnzip/mnzip.c
==============================================================================
--- trunk/mnzip/mnzip.c	(original)
+++ trunk/mnzip/mnzip.c	Fri Jun 15 02:29:18 2007
@@ -460,37 +460,14 @@ static inline int getbit(RangeCoder *c, 
     return b;
 }
 
-static inline void put_symbol(RangeCoder *c, uint32_t *state, int v){
-    int i;
-
-    if(v){
-        const int e= av_log2(v);
-        const int el= MIN(e, 8);
-        putbit(c, state+0, 0, prob[0]);
-
-        for(i=0; i<el; i++){
-            putbit(c, state+1+i, 1, prob[1+i]);  //1..8
-        }
-        for(; i<e; i++){
-            putbit(c, state+1+7, 1, prob[1+7]);  //1..8
-        }
-        putbit(c, state+1+MIN(i,7), 0, prob[1+MIN(i,7)]);
-
-        for(i=e-1; i>=el; i--){
-            putbit(c, state+9+7, (v>>i)&1, prob[9+7]); //9..16
-        }
-        for(; i>=0; i--){
-            putbit(c, state+9+i, (v>>i)&1, prob[9+i]); //9..16
-        }
-    }else{
-        putbit(c, state+0, 1, prob[0]);
-    }
-}
-
 static inline void put_symbol_255(RangeCoder *c, uint32_t *state, int v){
     const int e= av_log2(v);
     int i;
 
+    putbit(c, state+14,  v==0, prob[17+14]);  //14
+    if(!v)
+        return;
+
     assert(v);
     assert(e<8);
     putbit(c, state         ,  e>3    , prob[17]);  //0
@@ -504,6 +481,9 @@ static inline void put_symbol_255(RangeC
 static inline int get_symbol_255(RangeCoder *c, uint32_t *state){
     int e,a,i;
 
+    if(getbit(c, state+14, prob[17+14]))
+        return 0;
+
     e =4*getbit(c, state         , prob[17]);  //0
     e+=2*getbit(c, state+1+(e>3) , prob[17+1+(e>3)]);  //1..2
     e+=  getbit(c, state+3+(e>>1), prob[17+3+(e>>1)]);  //3..6
@@ -515,23 +495,6 @@ static inline int get_symbol_255(RangeCo
     return a;
 }
 
-static inline int get_symbol(RangeCoder *c, uint32_t *state){
-    if(getbit(c, state+0, prob[0]))
-        return 0;
-    else{
-        int i, e, a;
-        e= 0;
-        while(getbit(c, state+1 + MIN(e,7), prob[1 + MIN(e,7)])) //1..8
-            e++;
-
-        a= 1;
-        for(i=e-1; i>=0; i--)
-            a += a + getbit(c, state+9 + MIN(i,7), prob[9 + MIN(i,7)]); //9..16
-
-        return a;
-    }
-}
-
 static inline int rb32(uint8_t *p){
     return (p[0]<<24) + (p[1]<<16) + (p[2]<<8) + p[3];
 }
@@ -580,13 +543,11 @@ fprintf(stderr,"range coding (%d %d)\n",
     }
 
     for(i=0; i<256; i++){
-        put_symbol(&c, &state[256*32*2], mtf[i]);
+        put_symbol_255(&c, &state[256*32*2], mtf[i]);
     }
 
     for(i=0; i<len; i++){
-        int run, v, ndx;
-        for(run=0; i<len && !tmp[i]; i++) 
-            run++;
+        int v, ndx;
 
         ndx= tmp[i];
         v= mtf[0];
@@ -594,7 +555,6 @@ fprintf(stderr,"range coding (%d %d)\n",
             mtf[j]= mtf[j+1];
         mtf[ndx]= v;
         put_symbol_255(&c, &state[v*32], ndx);
-        put_symbol(&c, &state[256*32 + 32*v], run);
     }
 //FIXME  last byte mtf= 0 and run mess
 //FIXME right order mtf optim
@@ -649,7 +609,7 @@ fprintf(stderr," block (%d %d %d)\n", ou
 
     for(i=0; i<256; i++){
         int test[256]={0};
-        mtf[i]= get_symbol(&c, &state[256*32*2]);
+        mtf[i]= get_symbol_255(&c, &state[256*32*2]);
         if(mtf[i] > 255U || test[mtf[i]]++){
             fprintf(stderr, "fatal error mtf invalid\n");
             return -1;
@@ -659,20 +619,13 @@ fprintf(stderr," block (%d %d %d)\n", ou
     for(i=0; i<out_len; ){
         int v= mtf[0];
         int ndx= get_symbol_255(&c, &state[v*32]);
-        int run= get_symbol(&c, &state[256*32 + 32*v]) + 1;
 
         for(j=0; j<ndx; j++)
             mtf[j]= mtf[j+1];
         mtf[ndx]= v;
 
-        if(i+run > out_len || i+run<i){
-            fprintf(stderr, "fatal error, run to large\n");
-            return -1;
-        }
-        do{
-            tmp[i++]= v;
-            histogram[v]++;
-        }while(--run);
+        tmp[i++]= v;
+        histogram[v]++;
     }
 
     free(in);