--- a/libgsmefr/Makefile	Sat Nov 26 07:22:27 2022 +0000
+++ b/libgsmefr/Makefile	Sat Nov 26 07:30:53 2022 +0000
@@ -5,7 +5,7 @@
 	dec_lag6.o dtx.o e_homing.o enc_create.o enc_lag6.o frame2params.o \
 	g_code.o g_pitch.o int_lpc.o inter_6.o inv_sqrt.o lag_wind.o levinson.o\
 	log2.o lsp_az.o lsp_lsf.o oper_32b.o params2frame.o pitch_f6.o \
-	pitch_ol.o pow2.o sid_class.o sid_insert.o tls_flags.o
+	pitch_ol.o pow2.o pre_proc.o sid_class.o sid_insert.o tls_flags.o
 HDRS=	basic_op.h cnst.h codec.h d_homing.h dec_state.h dtx.h e_homing.h \
 	enc_state.h gains_tb.h gsm_efr.h memops.h namespace.h no_count.h \
 	oper_32b.h sig_proc.h typedef.h vad.h

--- a/libgsmefr/pre_proc.c	Sat Nov 26 07:22:27 2022 +0000
+++ b/libgsmefr/pre_proc.c	Sat Nov 26 07:30:53 2022 +0000
@@ -10,10 +10,15 @@
  *
  *************************************************************************/
 
+#include "gsm_efr.h"
 #include "typedef.h"
+#include "namespace.h"
 #include "basic_op.h"
 #include "oper_32b.h"
-#include "count.h"
+#include "no_count.h"
+#include "sig_proc.h"
+#include "cnst.h"
+#include "enc_state.h"
 
 /*------------------------------------------------------------------------*
  *                                                                        *
@@ -31,50 +36,49 @@
 static const Word16 b[3] = {1899, -3798, 1899};
 static const Word16 a[3] = {4096, 7807, -3733};
 
-/* Static values to be preserved between calls */
-/* y[] values are kept in double precision     */
-
-static Word16 y2_hi, y2_lo, y1_hi, y1_lo, x0, x1;
-
 /* Initialization of static values */
 
-void Init_Pre_Process (void)
+void Init_Pre_Process (struct EFR_encoder_state *st)
 {
-    y2_hi = 0;
-    y2_lo = 0;
-    y1_hi = 0;
-    y1_lo = 0;
-    x0 = 0;
-    x1 = 0;
+    struct preproc_state *pps = &st->pre_proc;
+
+    pps->y2_hi = 0;
+    pps->y2_lo = 0;
+    pps->y1_hi = 0;
+    pps->y1_lo = 0;
+    pps->x0 = 0;
+    pps->x1 = 0;
 }
 
 void Pre_Process (
+    struct EFR_encoder_state *st,
     Word16 signal[], /* input/output signal */
     Word16 lg)       /* lenght of signal    */
 {
+    struct preproc_state *pps = &st->pre_proc;
     Word16 i, x2;
     Word32 L_tmp;
 
     for (i = 0; i < lg; i++)
     {
-        x2 = x1;                   move16 (); 
-        x1 = x0;                   move16 (); 
-        x0 = signal[i];            move16 (); 
+        x2 = pps->x1;
+        pps->x1 = pps->x0;
+        pps->x0 = signal[i];
 
         /*  y[i] = b[0]*x[i]/2 + b[1]*x[i-1]/2 + b140[2]*x[i-2]/2  */
         /*                     + a[1]*y[i-1] + a[2] * y[i-2];      */
 
-        L_tmp = Mpy_32_16 (y1_hi, y1_lo, a[1]);
-        L_tmp = L_add (L_tmp, Mpy_32_16 (y2_hi, y2_lo, a[2]));
-        L_tmp = L_mac (L_tmp, x0, b[0]);
-        L_tmp = L_mac (L_tmp, x1, b[1]);
+        L_tmp = Mpy_32_16 (pps->y1_hi, pps->y1_lo, a[1]);
+        L_tmp = L_add (L_tmp, Mpy_32_16 (pps->y2_hi, pps->y2_lo, a[2]));
+        L_tmp = L_mac (L_tmp, pps->x0, b[0]);
+        L_tmp = L_mac (L_tmp, pps->x1, b[1]);
         L_tmp = L_mac (L_tmp, x2, b[2]);
         L_tmp = L_shl (L_tmp, 3);
-        signal[i] = round (L_tmp); move16 (); 
+        signal[i] = round (L_tmp);
 
-        y2_hi = y1_hi;             move16 (); 
-        y2_lo = y1_lo;             move16 (); 
-        L_Extract (L_tmp, &y1_hi, &y1_lo);
+        pps->y2_hi = pps->y1_hi;
+        pps->y2_lo = pps->y1_lo;
+        L_Extract (L_tmp, &pps->y1_hi, &pps->y1_lo);
     }
     return;
 }