--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libtwamr/c2_9pf.h	Thu Apr 18 19:31:03 2024 +0000
@@ -0,0 +1,95 @@
+/*
+*****************************************************************************
+*
+*      GSM AMR-NB speech codec   R98   Version 7.6.0   December 12, 2001
+*                                R99   Version 3.3.0                
+*                                REL-4 Version 4.1.0                
+*
+*****************************************************************************
+*
+*      File             : c2_9pf.h
+*      Purpose          : Searches a 9 bit algebraic codebook containing 
+*                         2 pulses in a frame of 40 samples.
+*
+*****************************************************************************
+*/
+#ifndef c2_9pf_h
+#define c2_9pf_h "$Id $"
+ 
+/*
+*****************************************************************************
+*                         INCLUDE FILES
+*****************************************************************************
+*/
+#include "typedef.h"
+
+/*
+*****************************************************************************
+*                         LOCAL VARIABLES AND TABLES
+*****************************************************************************
+*/
+
+/*
+*****************************************************************************
+*                         DEFINITION OF DATA TYPES
+*****************************************************************************
+*/
+
+/*
+*****************************************************************************
+*                         DECLARATION OF PROTOTYPES
+*****************************************************************************
+*/
+/*************************************************************************
+ *
+ *  FUNCTION:  code_2i40_9bits()
+ *
+ *  PURPOSE:  Searches a 9 bit algebraic codebook containing 2 pulses
+ *            in a frame of 40 samples.
+ *
+ *  DESCRIPTION:
+ *    The code length is 40, containing 2 nonzero pulses: i0...i1.
+ *    All pulses can have two possible amplitudes: +1 or -1.
+ *    Pulse i0 can have 8 possible positions, pulse i1 can have
+ *    8 positions. Also coded is which track pair should be used,
+ *    i.e. first or second pair. Where each pair contains 2 tracks.
+ *
+ *     First subframe:
+ *     first   i0 :  0, 5, 10, 15, 20, 25, 30, 35.
+ *             i1 :  2, 7, 12, 17, 22, 27, 32, 37.
+ *     second  i0 :  1, 6, 11, 16, 21, 26, 31, 36.
+ *             i1 :  3, 8, 13, 18, 23, 28, 33, 38.
+ *
+ *     Second subframe:
+ *     first   i0 :  0, 5, 10, 15, 20, 25, 30, 35.
+ *             i1 :  3, 8, 13, 18, 23, 28, 33, 38.
+ *     second  i0 :  2, 7, 12, 17, 22, 27, 32, 37.
+ *             i1 :  4, 9, 14, 19, 24, 29, 34, 39.
+ *
+ *     Third subframe:
+ *     first   i0 :  0, 5, 10, 15, 20, 25, 30, 35.
+ *             i1 :  2, 7, 12, 17, 22, 27, 32, 37.
+ *     second  i0 :  1, 6, 11, 16, 21, 26, 31, 36.
+ *             i1 :  4, 9, 14, 19, 24, 29, 34, 39.
+ *
+ *     Fourth subframe:
+ *     first   i0 :  0, 5, 10, 15, 20, 25, 30, 35.
+ *             i1 :  3, 8, 13, 18, 23, 28, 33, 38.
+ *     second  i0 :  1, 6, 11, 16, 21, 26, 31, 36.
+ *             i1 :  4, 9, 14, 19, 24, 29, 34, 39.
+ *
+ *************************************************************************/
+
+Word16 code_2i40_9bits(
+    Word16 subNr,       /* i : subframe number                               */
+    Word16 x[],         /* i : target vector                                 */
+    Word16 h[],         /* i : impulse response of weighted synthesis filter */
+                        /*     h[-L_subfr..-1] must be set to zero.          */
+    Word16 T0,          /* i : Pitch lag                                     */
+    Word16 pitch_sharp, /* i : Last quantized pitch gain                     */
+    Word16 code[],      /* o : Innovative codebook                           */
+    Word16 y[],         /* o : filtered fixed codebook excitation            */
+    Word16 * sign       /* o : Signs of 2 pulses                             */
+);
+
+#endif