--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/bits2prm.c	Wed Apr 03 05:31:37 2024 +0000
@@ -0,0 +1,99 @@
+/*************************************************************************
+ *
+ *  FUNCTION:  Bits2prm_12k2
+ *
+ *  PURPOSE: Retrieves the vector of encoder parameters from the received
+ *           serial bits in a frame.
+ *
+ *  DESCRIPTION: The encoder parameters are:
+ *
+ *     BFI      bad frame indicator      1 bit
+ *
+ *     LPC:
+ *              1st codebook             7 bit
+ *              2nd codebook             8 bit
+ *              3rd codebook             8+1 bit
+ *              4th codebook             8 bit
+ *              5th codebook             6 bit
+ *
+ *     1st and 3rd subframes:
+ *           pitch period                9 bit
+ *           pitch gain                  4 bit
+ *           codebook index              35 bit
+ *           codebook gain               5 bit
+ *
+ *     2nd and 4th subframes:
+ *           pitch period                6 bit
+ *           pitch gain                  4 bit
+ *           codebook index              35 bit
+ *           codebook gain               5 bit
+ *
+ *************************************************************************/
+
+#include "typedef.h"
+#include "basic_op.h"
+#include "count.h"
+
+/* Local function */
+
+Word16 Bin2int (        /* Reconstructed parameter                      */
+    Word16 no_of_bits,  /* input : number of bits associated with value */
+    Word16 *bitstream   /* output: address where bits are written       */
+);
+
+#define BIT_0     0
+#define BIT_1     1
+#define PRM_NO    57
+
+void Bits2prm_12k2 (
+    Word16 bits[],      /* input : serial bits (244 + bfi)                */
+    Word16 prm[]        /* output: analysis parameters  (57+1 parameters) */
+)
+{
+    Word16 i;
+
+    static const Word16 bitno[PRM_NO] =
+    {
+        7, 8, 9, 8, 6,                          /* LSP VQ          */
+        9, 4, 4, 4, 4, 4, 4, 3, 3, 3, 3, 3, 5,  /* first subframe  */
+        6, 4, 4, 4, 4, 4, 4, 3, 3, 3, 3, 3, 5,  /* second subframe */
+        9, 4, 4, 4, 4, 4, 4, 3, 3, 3, 3, 3, 5,  /* third subframe  */
+        6, 4, 4, 4, 4, 4, 4, 3, 3, 3, 3, 3, 5}; /* fourth subframe */
+
+    *prm++ = *bits++;                           move16 (); /* read BFI */
+
+    for (i = 0; i < PRM_NO; i++)
+    {
+        prm[i] = Bin2int (bitno[i], bits);      move16 (); 
+        bits += bitno[i];
+    }
+    return;
+}
+
+/*************************************************************************
+ *
+ *  FUNCTION:  Bin2int                   
+ *
+ *  PURPOSE: Read "no_of_bits" bits from the array bitstream[] and convert
+ *           to integer.
+ *
+ *************************************************************************/
+
+Word16 Bin2int (        /* Reconstructed parameter                      */
+    Word16 no_of_bits,  /* input : number of bits associated with value */
+    Word16 *bitstream   /* output: address where bits are written       */
+)
+{
+    Word16 value, i, bit;
+
+    value = 0;                                  move16 (); 
+    for (i = 0; i < no_of_bits; i++)
+    {
+        value = shl (value, 1);
+        bit = *bitstream++;                     move16 (); 
+        test (); 
+        if (sub (bit, BIT_1) == 0)
+            value = add (value, 1);
+    }
+    return (value);
+}