--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libtwamr/ol_ltp.c	Tue May 07 03:21:14 2024 +0000
@@ -0,0 +1,98 @@
+/*
+********************************************************************************
+*
+*      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             : ol_ltp.c
+*      Purpose          : Compute the open loop pitch lag.
+*
+********************************************************************************
+*/
+
+/*
+********************************************************************************
+*                         MODULE INCLUDE FILE AND VERSION ID
+********************************************************************************
+*/
+#include "namespace.h"
+#include "ol_ltp.h"
+ 
+/*
+********************************************************************************
+*                         INCLUDE FILES
+********************************************************************************
+*/
+#include "typedef.h"
+#include "cnst.h"
+#include "pitch_ol.h"
+#include "p_ol_wgh.h"
+#include "no_count.h"
+#include "basic_op.h"
+
+/*
+********************************************************************************
+*                         LOCAL VARIABLES AND TABLES
+********************************************************************************
+*/
+
+/*
+********************************************************************************
+*                         PUBLIC PROGRAM CODE
+********************************************************************************
+*/
+int ol_ltp(
+    pitchOLWghtState *st, /* i/o : State struct                            */
+    vadState *vadSt,      /* i/o : VAD state struct                        */
+    enum Mode mode,       /* i   : coder mode                              */
+    Word16 wsp[],         /* i   : signal used to compute the OL pitch, Q0 */
+                          /*       uses signal[-pit_max] to signal[-1]     */
+    Word16 *T_op,         /* o   : open loop pitch lag,                 Q0 */
+    Word16 old_lags[],    /* i   : history with old stored Cl lags         */
+    Word16 ol_gain_flg[], /* i   : OL gain flag                            */
+    Word16 idx,           /* i   : index                                   */
+    Flag dtx              /* i   : dtx flag; use dtx=1, do not use dtx=0   */
+    )
+{
+   test ();   
+   if (sub (mode, MR102) != 0 )
+   {
+      ol_gain_flg[0] = 0;                                       move16 ();
+      ol_gain_flg[1] = 0;                                       move16 ();
+   }
+   
+   test (); test ();
+   if (sub (mode, MR475) == 0 || sub (mode, MR515) == 0 )
+   {
+      *T_op = Pitch_ol(vadSt, mode, wsp, PIT_MIN, PIT_MAX, L_FRAME, idx, dtx);
+                                                                move16 ();
+   }
+   else
+   {
+      if ( sub (mode, MR795) <= 0 )
+      {
+         test();
+         *T_op = Pitch_ol(vadSt, mode, wsp, PIT_MIN, PIT_MAX, L_FRAME_BY2,
+                          idx, dtx);
+                                                                move16 ();
+      }
+      else if ( sub (mode, MR102) == 0 )
+      {
+         test(); test();
+         *T_op = Pitch_ol_wgh(st, vadSt, wsp, PIT_MIN, PIT_MAX, L_FRAME_BY2,
+                              old_lags, ol_gain_flg, idx, dtx);
+                                                                move16 ();
+      }
+      else
+      {
+         test(); test();          
+         *T_op = Pitch_ol(vadSt, mode, wsp, PIT_MIN_MR122, PIT_MAX,
+                          L_FRAME_BY2, idx, dtx);
+                                                                move16 ();
+      }
+   }
+   return 0;
+}