1 files changed, 175 insertions, 0 deletions
diff --git a/trunk/codecs/ilbc/packing.c b/trunk/codecs/ilbc/packing.c
new file mode 100644
index 000000000..3071032e0
--- /dev/null
+++ b/trunk/codecs/ilbc/packing.c
@@ -0,0 +1,175 @@
+
+/******************************************************************
+
+    iLBC Speech Coder ANSI-C Source Code
+
+    packing.c 
+
+    Copyright (C) The Internet Society (2004). 
+    All Rights Reserved.
+
+******************************************************************/
+
+#include <math.h>
+#include <stdlib.h>
+
+#include "iLBC_define.h"
+#include "constants.h"
+#include "helpfun.h"
+#include "packing.h"
+#include "string.h"
+
+/*----------------------------------------------------------------*
+ *  splitting an integer into first most significant bits and 
+ *  remaining least significant bits
+ *---------------------------------------------------------------*/
+
+void packsplit(
+    int *index,                 /* (i) the value to split */
+    int *firstpart,             /* (o) the value specified by most 
+                                       significant bits */
+    int *rest,                  /* (o) the value specified by least
+                                       significant bits */
+    int bitno_firstpart,    /* (i) number of bits in most 
+                                       significant part */
+    int bitno_total             /* (i) number of bits in full range
+                                       of value */
+){
+    int bitno_rest = bitno_total-bitno_firstpart;
+
+
+
+    *firstpart = *index>>(bitno_rest);
+    *rest = *index-(*firstpart<<(bitno_rest));
+}
+
+/*----------------------------------------------------------------*
+ *  combining a value corresponding to msb's with a value 
+ *  corresponding to lsb's
+ *---------------------------------------------------------------*/
+
+void packcombine( 
+    int *index,                 /* (i/o) the msb value in the 
+                                       combined value out */
+    int rest,                   /* (i) the lsb value */
+    int bitno_rest              /* (i) the number of bits in the 
+                                       lsb part */
+){
+    *index = *index<<bitno_rest;
+    *index += rest;
+}
+
+/*----------------------------------------------------------------*
+ *  packing of bits into bitstream, i.e., vector of bytes
+ *---------------------------------------------------------------*/
+
+void dopack( 
+    unsigned char **bitstream,  /* (i/o) on entrance pointer to 
+                                       place in bitstream to pack 
+                                       new data, on exit pointer 
+                                       to place in bitstream to 
+                                       pack future data */
+    int index,                  /* (i) the value to pack */
+    int bitno,                  /* (i) the number of bits that the 
+                                       value will fit within */
+    int *pos                /* (i/o) write position in the 
+                                       current byte */
+){
+    int posLeft;
+    
+    /* Clear the bits before starting in a new byte */
+    
+    if ((*pos)==0) {
+        **bitstream=0;
+    }
+
+    while (bitno>0) {
+        
+        /* Jump to the next byte if end of this byte is reached*/
+        
+        if (*pos==8) {
+            *pos=0;
+            (*bitstream)++;
+            **bitstream=0;
+        }
+
+
+
+        posLeft=8-(*pos);
+
+        /* Insert index into the bitstream */
+        
+        if (bitno <= posLeft) {
+            **bitstream |= (unsigned char)(index<<(posLeft-bitno));
+            *pos+=bitno;
+            bitno=0;
+        } else {
+            **bitstream |= (unsigned char)(index>>(bitno-posLeft));
+            
+            *pos=8;
+            index-=((index>>(bitno-posLeft))<<(bitno-posLeft));
+            
+            bitno-=posLeft;
+        }
+    }
+}
+
+/*----------------------------------------------------------------*
+ *  unpacking of bits from bitstream, i.e., vector of bytes
+ *---------------------------------------------------------------*/
+
+void unpack( 
+    unsigned char **bitstream,  /* (i/o) on entrance pointer to 
+                                       place in bitstream to 
+                                       unpack new data from, on 
+                                       exit pointer to place in 
+                                       bitstream to unpack future 
+                                       data from */
+    int *index,                 /* (o) resulting value */
+    int bitno,                  /* (i) number of bits used to 
+                                       represent the value */
+    int *pos                /* (i/o) read position in the 
+                                       current byte */
+){
+    int BitsLeft;
+
+    *index=0;
+
+    while (bitno>0) {
+        
+        /* move forward in bitstream when the end of the 
+           byte is reached */
+        
+        if (*pos==8) {
+            *pos=0;
+            (*bitstream)++;
+        }
+
+        BitsLeft=8-(*pos);
+
+        /* Extract bits to index */
+        
+
+
+        if (BitsLeft>=bitno) {
+            *index+=((((**bitstream)<<(*pos)) & 0xFF)>>(8-bitno));
+            
+            *pos+=bitno;
+            bitno=0;
+        } else {
+            
+            if ((8-bitno)>0) {
+                *index+=((((**bitstream)<<(*pos)) & 0xFF)>>
+                    (8-bitno));
+                *pos=8;
+            } else {
+                *index+=(((int)(((**bitstream)<<(*pos)) & 0xFF))<<
+                    (bitno-8));
+                *pos=8;
+            }
+            bitno-=BitsLeft;
+        }
+    }
+}
+
+