shithub: sox

Download patch

ref: 92ba81db75c5b673ce4d1d561a97d3296ebad4df
parent: 50a063bfb3b6180b2893dc3ae1d3b143643efa77
author: cbagwell <cbagwell>
date: Thu Sep 6 12:50:55 EDT 2007

Since libgsm must be compiled before linking in src, move to parent.
This works with wider range of automakes.

diff: cannot open b/libgsm//null: file does not exist: 'b/libgsm//null'
--- a/Makefile.am
+++ b/Makefile.am
@@ -2,11 +2,11 @@
 
 ACLOCAL_AMFLAGS = -I m4
 
-SUBDIRS = lpc10 src
+SUBDIRS = lpc10 libgsm src
 if HAVE_LIBLTDL
 SUBDIRS += libltdl
 endif
-DIST_SUBDIRS = libltdl lpc10 src
+DIST_SUBDIRS = libltdl lpc10 libgsm src
 
 RM = rm -f
 
--- a/configure.ac
+++ b/configure.ac
@@ -186,7 +186,7 @@
     AC_CHECK_LIB(gsm, gsm_create, GSM_LIBS="$GSM_LIBS -lgsm")
     AC_DEFINE(EXTERNAL_GSM, 1, [Define if you are using an external GSM library])
 else
-    LIBGSM_LIBADD=libgsm/libgsm.la
+    LIBGSM_LIBADD=../libgsm/libgsm.la
 fi
 AC_SUBST(LIBGSM_LIBADD)
 AC_SUBST(GSM_LIBS)
@@ -378,7 +378,7 @@
 
 dnl Generate output files.
 AX_CREATE_STDINT_H(src/soxstdint.h)
-AC_CONFIG_FILES(Makefile src/Makefile src/libgsm/Makefile lpc10/Makefile)
+AC_CONFIG_FILES(Makefile src/Makefile libgsm/Makefile lpc10/Makefile)
 AC_OUTPUT
 
 if test "$found_libgsm" = "yes"; then
--- /dev/null
+++ b/libgsm/CMakeLists.txt
@@ -1,0 +1,1 @@
+add_library(gsm add code decode gsm_create gsm_decode gsm_destroy gsm_encode gsm_option long_term lpc preprocess rpe short_term table)
--- /dev/null
+++ b/libgsm/Makefile.am
@@ -1,0 +1,39 @@
+SASR    = -DSASR
+######### Define SASR if >> is a signed arithmetic shift (-1 >> 1 == -1)
+
+MULHACK = -DUSE_FLOAT_MUL
+######### Define this if your host multiplies floats faster than integers,
+######### e.g. on a SPARCstation.
+
+FAST    = -DFAST
+######### Define together with USE_FLOAT_MUL to enable the GSM library's
+######### approximation option for incorrect, but good-enough results.
+
+# LTP_CUT       = -DLTP_CUT
+LTP_CUT =
+######### Define to enable the GSM library's long-term correlation 
+######### approximation option---faster, but worse; works for
+######### both integer and floating point multiplications.
+######### This flag is still in the experimental stage.
+
+WAV49   = -DWAV49
+#WAV49  =
+######### Define to enable the GSM library's option to pack GSM frames 
+######### in the style used by the WAV #49 format.  If you want to write
+######### a tool that produces .WAV files which contain GSM-encoded data,
+######### define this, and read about the GSM_OPT_WAV49 option in the
+######### manual page on gsm_option(3).
+
+AM_CFLAGS = $(SASR) $(MULHAC) $(FAST) $(LTP_CUT) $(WAV49) 
+
+if EXTERNAL_GSM
+EXTRA_DIST = add.c code.c decode.c long_term.c lpc.c preprocess.c \
+	     rpe.c gsm_destroy.c gsm_decode.c gsm_encode.c gsm_create.c \
+	     gsm_option.c short_term.c table.c private.h gsm.h
+else
+noinst_LTLIBRARIES = libgsm.la
+noinst_HEADERS = gsm.h
+libgsm_la_SOURCES = add.c code.c decode.c long_term.c lpc.c preprocess.c \
+		rpe.c gsm_destroy.c gsm_decode.c gsm_encode.c gsm_create.c \
+		gsm_option.c short_term.c table.c private.h
+endif
--- /dev/null
+++ b/libgsm/add.c
@@ -1,0 +1,234 @@
+/*
+ * Copyright 1992 by Jutta Degener and Carsten Bormann, Technische
+ * Universitaet Berlin.  See the accompanying file "COPYRIGHT" for
+ * details.  THERE IS ABSOLUTELY NO WARRANTY FOR THIS SOFTWARE.
+ */
+
+/* $Header: /cvsroot/sox/sox/libgsm/add.c,v 1.1 2007/09/06 16:50:55 cbagwell Exp $ */
+
+/*
+ *  See private.h for the more commonly used macro versions.
+ */
+
+#include	<stdio.h>
+#include	<assert.h>
+
+#include	"private.h"
+#include	"gsm.h"
+
+#define	saturate(x) 	\
+	((x) < MIN_WORD ? MIN_WORD : (x) > MAX_WORD ? MAX_WORD: (x))
+
+word gsm_add (word a, word b)
+{
+	longword sum = (longword)a + (longword)b;
+	return saturate(sum);
+}
+
+word gsm_sub (word a, word b)
+{
+	longword diff = (longword)a - (longword)b;
+	return saturate(diff);
+}
+
+word gsm_mult (word a, word b)
+{
+	if (a == MIN_WORD && b == MIN_WORD) return MAX_WORD;
+	else return SASR( (longword)a * (longword)b, 15 );
+}
+
+word gsm_mult_r (word a, word b)
+{
+	if (b == MIN_WORD && a == MIN_WORD) return MAX_WORD;
+	else {
+		longword prod = (longword)a * (longword)b + 16384;
+		prod >>= 15;
+		return prod & 0xFFFF;
+	}
+}
+
+word gsm_abs (word a)
+{
+	return a < 0 ? (a == MIN_WORD ? MAX_WORD : -a) : a;
+}
+
+longword gsm_L_mult (word a, word b)
+{
+	assert( a != MIN_WORD || b != MIN_WORD );
+	return ((longword)a * (longword)b) << 1;
+}
+
+longword gsm_L_add (longword a, longword b)
+{
+	if (a < 0) {
+		if (b >= 0) return a + b;
+		else {
+			ulongword A = (ulongword)-(a + 1) + (ulongword)-(b + 1);
+			return A >= MAX_LONGWORD ? MIN_LONGWORD :-(longword)A-2;
+		}
+	}
+	else if (b <= 0) return a + b;
+	else {
+		ulongword A = (ulongword)a + (ulongword)b;
+		return A > MAX_LONGWORD ? MAX_LONGWORD : A;
+	}
+}
+
+longword gsm_L_sub (longword a, longword b)
+{
+	if (a >= 0) {
+		if (b >= 0) return a - b;
+		else {
+			/* a>=0, b<0 */
+
+			ulongword A = (ulongword)a + -(b + 1);
+			return A >= MAX_LONGWORD ? MAX_LONGWORD : (A + 1);
+		}
+	}
+	else if (b <= 0) return a - b;
+	else {
+		/* a<0, b>0 */  
+
+		ulongword A = (ulongword)-(a + 1) + b;
+		return A >= MAX_LONGWORD ? MIN_LONGWORD : -(longword)A - 1;
+	}
+}
+
+static unsigned char const bitoff[ 256 ] = {
+	 8, 7, 6, 6, 5, 5, 5, 5, 4, 4, 4, 4, 4, 4, 4, 4,
+	 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
+	 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+	 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+	 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+	 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+	 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+	 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+	 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+	 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+	 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+	 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+	 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+	 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+	 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+	 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
+};
+
+word gsm_norm (longword a )
+/*
+ * the number of left shifts needed to normalize the 32 bit
+ * variable L_var1 for positive values on the interval
+ *
+ * with minimum of
+ * minimum of 1073741824  (01000000000000000000000000000000) and 
+ * maximum of 2147483647  (01111111111111111111111111111111)
+ *
+ *
+ * and for negative values on the interval with
+ * minimum of -2147483648 (-10000000000000000000000000000000) and
+ * maximum of -1073741824 ( -1000000000000000000000000000000).
+ *
+ * in order to normalize the result, the following
+ * operation must be done: L_norm_var1 = L_var1 << norm( L_var1 );
+ *
+ * (That's 'ffs', only from the left, not the right..)
+ */
+{
+	assert(a != 0);
+
+	if (a < 0) {
+		if (a <= -1073741824) return 0;
+		a = ~a;
+	}
+
+	return    a & 0xffff0000 
+		? ( a & 0xff000000
+		  ?  -1 + bitoff[ 0xFF & (a >> 24) ]
+		  :   7 + bitoff[ 0xFF & (a >> 16) ] )
+		: ( a & 0xff00
+		  ?  15 + bitoff[ 0xFF & (a >> 8) ]
+		  :  23 + bitoff[ 0xFF & a ] );
+}
+
+longword gsm_L_asl (longword a, int n)
+{
+	if (n >= 32) return 0;
+	if (n <= -32) return -(a < 0);
+	if (n < 0) return gsm_L_asr(a, -n);
+	return a << n;
+}
+
+word gsm_asl (word a, int n)
+{
+	if (n >= 16) return 0;
+	if (n <= -16) return -(a < 0);
+	if (n < 0) return gsm_asr(a, -n);
+	return a << n;
+}
+
+longword gsm_L_asr (longword a, int n)
+{
+	if (n >= 32) return -(a < 0);
+	if (n <= -32) return 0;
+	if (n < 0) return a << -n;
+
+#	ifdef	SASR
+		return a >> n;
+#	else
+		if (a >= 0) return a >> n;
+		else return -(longword)( -(ulongword)a >> n );
+#	endif
+}
+
+word gsm_asr (word a, int n)
+{
+	if (n >= 16) return -(a < 0);
+	if (n <= -16) return 0;
+	if (n < 0) return a << -n;
+
+#	ifdef	SASR
+		return a >> n;
+#	else
+		if (a >= 0) return a >> n;
+		else return -(word)( -(uword)a >> n );
+#	endif
+}
+
+/* 
+ *  (From p. 46, end of section 4.2.5)
+ *
+ *  NOTE: The following lines gives [sic] one correct implementation
+ *  	  of the div(num, denum) arithmetic operation.  Compute div
+ *        which is the integer division of num by denum: with denum
+ *	  >= num > 0
+ */
+
+word gsm_div (word num, word denum)
+{
+	longword	L_num   = num;
+	longword	L_denum = denum;
+	word		div 	= 0;
+	int		k 	= 15;
+
+	/* The parameter num sometimes becomes zero.
+	 * Although this is explicitly guarded against in 4.2.5,
+	 * we assume that the result should then be zero as well.
+	 */
+
+	/* assert(num != 0); */
+
+	assert(num >= 0 && denum >= num);
+	if (num == 0)
+	    return 0;
+
+	while (k--) {
+		div   <<= 1;
+		L_num <<= 1;
+
+		if (L_num >= L_denum) {
+			L_num -= L_denum;
+			div++;
+		}
+	}
+
+	return div;
+}
--- /dev/null
+++ b/libgsm/code.c
@@ -1,0 +1,91 @@
+/*
+ * Copyright 1992 by Jutta Degener and Carsten Bormann, Technische
+ * Universitaet Berlin.  See the accompanying file "COPYRIGHT" for
+ * details.  THERE IS ABSOLUTELY NO WARRANTY FOR THIS SOFTWARE.
+ */
+
+/* $Header: /cvsroot/sox/sox/libgsm/code.c,v 1.1 2007/09/06 16:50:55 cbagwell Exp $ */
+
+#include	<stdlib.h>
+#include	<string.h>
+
+#include	"private.h"
+#include	"gsm.h"
+
+/* 
+ *  4.2 FIXED POINT IMPLEMENTATION OF THE RPE-LTP CODER 
+ */
+
+void Gsm_Coder (
+
+	struct gsm_state	* S,
+
+	word	* s,	/* [0..159] samples		  	IN	*/
+
+/*
+ * The RPE-LTD coder works on a frame by frame basis.  The length of
+ * the frame is equal to 160 samples.  Some computations are done
+ * once per frame to produce at the output of the coder the
+ * LARc[1..8] parameters which are the coded LAR coefficients and 
+ * also to realize the inverse filtering operation for the entire
+ * frame (160 samples of signal d[0..159]).  These parts produce at
+ * the output of the coder:
+ */
+
+	word	* LARc,	/* [0..7] LAR coefficients		OUT	*/
+
+/*
+ * Procedure 4.2.11 to 4.2.18 are to be executed four times per
+ * frame.  That means once for each sub-segment RPE-LTP analysis of
+ * 40 samples.  These parts produce at the output of the coder:
+ */
+
+	word	* Nc,	/* [0..3] LTP lag			OUT 	*/
+	word	* bc,	/* [0..3] coded LTP gain		OUT 	*/
+	word	* Mc,	/* [0..3] RPE grid selection		OUT     */
+	word	* xmaxc,/* [0..3] Coded maximum amplitude	OUT	*/
+	word	* xMc	/* [13*4] normalized RPE samples	OUT	*/
+)
+{
+	int	k;
+	word	* dp  = S->dp0 + 120;	/* [ -120...-1 ] */
+	word	* dpp = dp;		/* [ 0...39 ]	 */
+
+	static word e[50];
+
+	word	so[160];
+
+	Gsm_Preprocess			(S, s, so);
+	Gsm_LPC_Analysis		(S, so, LARc);
+	Gsm_Short_Term_Analysis_Filter	(S, LARc, so);
+
+	for (k = 0; k <= 3; k++, xMc += 13) {
+
+		Gsm_Long_Term_Predictor	( S,
+					 so+k*40, /* d      [0..39] IN	*/
+					 dp,	  /* dp  [-120..-1] IN	*/
+					e + 5,	  /* e      [0..39] OUT	*/
+					dpp,	  /* dpp    [0..39] OUT */
+					 Nc++,
+					 bc++);
+
+		Gsm_RPE_Encoding	( S,
+					e + 5,	/* e	  ][0..39][ IN/OUT */
+					  xmaxc++, Mc++, xMc );
+		/*
+		 * Gsm_Update_of_reconstructed_short_time_residual_signal
+		 *			( dpp, e + 5, dp );
+		 */
+
+		{ register int i;
+		  register longword ltmp;
+		  for (i = 0; i <= 39; i++)
+			dp[ i ] = GSM_ADD( e[5 + i], dpp[i] );
+		}
+		dp  += 40;
+		dpp += 40;
+
+	}
+	(void)memcpy( (char *)S->dp0, (char *)(S->dp0 + 160),
+		120 * sizeof(*S->dp0) );
+}
--- /dev/null
+++ b/libgsm/decode.c
@@ -1,0 +1,62 @@
+/*
+ * Copyright 1992 by Jutta Degener and Carsten Bormann, Technische
+ * Universitaet Berlin.  See the accompanying file "COPYRIGHT" for
+ * details.  THERE IS ABSOLUTELY NO WARRANTY FOR THIS SOFTWARE.
+ */
+
+/* $Header: /cvsroot/sox/sox/libgsm/decode.c,v 1.1 2007/09/06 16:50:55 cbagwell Exp $ */
+
+#include <stdio.h>
+
+#include	"private.h"
+#include	"gsm.h"
+
+/*
+ *  4.3 FIXED POINT IMPLEMENTATION OF THE RPE-LTP DECODER
+ */
+
+static void Postprocessing (
+	struct gsm_state	* S,
+	register word 		* s)
+{
+	register int		k;
+	register word		msr = S->msr;
+	register longword	ltmp;	/* for GSM_ADD */
+	register word		tmp;
+
+	for (k = 160; k--; s++) {
+		tmp = GSM_MULT_R( msr, 28180 );
+		msr = GSM_ADD(*s, tmp);  	   /* Deemphasis 	     */
+		*s  = GSM_ADD(msr, msr) & 0xFFF8;  /* Truncation & Upscaling */
+	}
+	S->msr = msr;
+}
+
+void Gsm_Decoder (
+	struct gsm_state	* S,
+
+	word		* LARcr,	/* [0..7]		IN	*/
+
+	word		* Ncr,		/* [0..3] 		IN 	*/
+	word		* bcr,		/* [0..3]		IN	*/
+	word		* Mcr,		/* [0..3] 		IN 	*/
+	word		* xmaxcr,	/* [0..3]		IN 	*/
+	word		* xMcr,		/* [0..13*4]		IN	*/
+
+	word		* s)		/* [0..159]		OUT 	*/
+{
+	int		j, k;
+	word		erp[40], wt[160];
+	word		* drp = S->dp0 + 120;
+
+	for (j=0; j <= 3; j++, xmaxcr++, bcr++, Ncr++, Mcr++, xMcr += 13) {
+
+		Gsm_RPE_Decoding( S, *xmaxcr, *Mcr, xMcr, erp );
+		Gsm_Long_Term_Synthesis_Filtering( S, *Ncr, *bcr, erp, drp );
+
+		for (k = 0; k <= 39; k++) wt[ j * 40 + k ] =  drp[ k ];
+	}
+
+	Gsm_Short_Term_Synthesis_Filter( S, LARcr, wt, s );
+	Postprocessing(S, s);
+}
--- /dev/null
+++ b/libgsm/gsm.3
@@ -1,0 +1,105 @@
+.\"
+.\" Copyright 1992 by Jutta Degener and Carsten Bormann, Technische
+.\" Universitaet Berlin.  See the accompanying file "COPYRIGHT" for
+.\" details.  THERE IS ABSOLUTELY NO WARRANTY FOR THIS SOFTWARE.
+.\"
+.PU
+.TH GSM 3 
+.SH NAME
+gsm_create, gsm_destroy, gsm_encode, gsm_decode \(em GSM\ 06.10 lossy sound compression
+.SH SYNOPSIS
+.PP
+#include "gsm.h"
+.PP
+gsm gsm_create();
+.PP
+void gsm_encode(handle, src, dst)
+.br
+gsm handle;
+.br
+gsm_signal src[160];
+.br
+gsm_frame dst;
+.PP
+int gsm_decode(handle, src, dst)
+.br
+gsm handle;
+.br
+gsm_frame src;
+.br
+gsm_signal dst[160];
+.PP
+void gsm_destroy(handle)
+.br
+gsm handle;
+.br
+.SH "DESCRIPTION"
+Gsm is an implementation of the final draft GSM 06.10
+standard for full-rate speech transcoding.
+.PP
+gsm_create() initializes a gsm pass and returns a 'gsm' object
+which can be used as a handle in subsequent calls to gsm_decode(),
+gsm_encode() or gsm_destroy().
+.PP
+gsm_encode() encodes an array of 160 13-bit samples (given as
+gsm_signal's, signed integral values of at least 16 bits) into
+a gsm_frame of 33 bytes.
+(gsm_frame is a type defined as an array of 33 gsm_bytes in gsm.h.)
+.PP
+gsm_decode() decodes a gsm_frame into an array of 160 13-bit samples
+(given as gsm_signals), which sound rather like what you handed to
+gsm_encode() on the other side of the wire.
+.PP
+gsm_destroy() finishes a gsm pass and frees all storage associated
+with it.
+.SS "Sample format"
+The following scaling is assumed for input to the algorithm:
+.br
+.nf
+   0  1                             11 12
+   S..v..v..v..v..v..v..v..v..v..v..v..v..*..*..*
+.nf
+.br
+Only the top 13 bits are used as a signed input value.
+The output of gsm_decode() has the three lower bits set to zero.
+.\" .SH OPTIONS
+.SH "RETURN VALUE"
+gsm_create() returns an opaque handle object of type gsm, or 0 on error.
+gsm_decode() returns -1 if the passed frame is invalid, else 0.
+.SH EXAMPLE
+.nf
+#include "gsm.h"
+
+gsm handle;
+gsm_frame buf;
+gsm_signal sample[160];
+int cc, soundfd;
+
+play() {	/* read compressed data from standard input, write to soundfd */
+
+	if (!(handle = gsm_create())) error...
+	while (cc = read(0, (char *)buf, sizeof buf)) {
+		if (cc != sizeof buf) error...
+		if (gsm_decode(handle, buf, sample) < 0) error... 
+		if (write(soundfd, sample, sizeof sample) != sizeof sample)
+			error...
+	}
+	gsm_destroy(handle);
+}
+
+record() {	/* read from soundfd, write compressed to standard output */
+
+	if (!(handle = gsm_create())) error...
+	while (cc = read(soundfd, sample, sizeof sample)) {
+		if (cc != sizeof sample) error...
+		gsm_encode(handle, sample, buf);
+		if (write(1, (char *)buf, sizeof buf) != sizeof sample) 
+			error...
+	}
+	gsm_destroy(handle);
+}
+.nf
+.SH BUGS
+Please direct bug reports to jutta@cs.tu-berlin.de and cabo@cs.tu-berlin.de.
+.SH "SEE ALSO"
+toast(1), gsm_print(3), gsm_explode(3), gsm_option(3)
--- /dev/null
+++ b/libgsm/gsm.h
@@ -1,0 +1,67 @@
+/*
+ * Copyright 1992 by Jutta Degener and Carsten Bormann, Technische
+ * Universitaet Berlin.  See the accompanying file "COPYRIGHT" for
+ * details.  THERE IS ABSOLUTELY NO WARRANTY FOR THIS SOFTWARE.
+ */
+
+/*$Header: /cvsroot/sox/sox/libgsm/gsm.h,v 1.1 2007/09/06 16:50:55 cbagwell Exp $*/
+
+#ifndef	GSM_H
+#define	GSM_H
+
+#ifdef __cplusplus
+#	define	NeedFunctionPrototypes	1
+#endif
+
+#if __STDC__
+#	define	NeedFunctionPrototypes	1
+#endif
+
+#ifdef _NO_PROTO
+#	undef	NeedFunctionPrototypes
+#endif
+
+#ifdef NeedFunctionPrototypes
+#   include	<stdio.h>		/* for FILE * 	*/
+#endif
+
+#undef GSM_P
+#if NeedFunctionPrototypes
+#	define	GSM_P( protos )	protos
+#else
+#	define  GSM_P( protos )	( /* protos */ )
+#endif
+
+/*
+ *	Interface
+ */
+
+typedef struct gsm_state * 	gsm;
+typedef short		   	gsm_signal;		/* signed 16 bit */
+typedef unsigned char		gsm_byte;
+typedef gsm_byte 		gsm_frame[33];		/* 33 * 8 bits	 */
+
+#define	GSM_MAGIC		0xD		  	/* 13 kbit/s RPE-LTP */
+
+#define	GSM_PATCHLEVEL		10
+#define	GSM_MINOR		0
+#define	GSM_MAJOR		1
+
+#define	GSM_OPT_VERBOSE		1
+#define	GSM_OPT_FAST		2
+#define	GSM_OPT_LTP_CUT		3
+#define	GSM_OPT_WAV49		4
+#define	GSM_OPT_FRAME_INDEX	5
+#define	GSM_OPT_FRAME_CHAIN	6
+
+extern gsm  gsm_create 	GSM_P((void));
+extern void gsm_destroy GSM_P((gsm));	
+
+extern int  gsm_option  GSM_P((gsm, int, int *));
+
+extern void gsm_encode  GSM_P((gsm, gsm_signal *, gsm_byte  *));
+extern int  gsm_decode  GSM_P((gsm, gsm_byte   *, gsm_signal *));
+
+#undef	GSM_P
+
+#endif	/* GSM_H */
--- /dev/null
+++ b/libgsm/gsm_create.c
@@ -1,0 +1,27 @@
+/*
+ * Copyright 1992 by Jutta Degener and Carsten Bormann, Technische
+ * Universitaet Berlin.  See the accompanying file "COPYRIGHT" for
+ * details.  THERE IS ABSOLUTELY NO WARRANTY FOR THIS SOFTWARE.
+ */
+
+static char const	ident[] = "$Header: /cvsroot/sox/sox/libgsm/gsm_create.c,v 1.1 2007/09/06 16:50:55 cbagwell Exp $";
+
+#include <string.h>
+#include <stdlib.h>
+#include <stdio.h>
+
+#include "gsm.h"
+#include "private.h"
+
+gsm gsm_create ()
+{
+	gsm  r;
+
+	r = (gsm)malloc(sizeof(struct gsm_state));
+	if (!r) return r;
+
+	memset((char *)r, 0, sizeof(*r));
+	r->nrp = 40;
+
+	return r;
+}
--- /dev/null
+++ b/libgsm/gsm_decode.c
@@ -1,0 +1,360 @@
+/*
+ * Copyright 1992 by Jutta Degener and Carsten Bormann, Technische
+ * Universitaet Berlin.  See the accompanying file "COPYRIGHT" for
+ * details.  THERE IS ABSOLUTELY NO WARRANTY FOR THIS SOFTWARE.
+ */
+
+/* $Header: /cvsroot/sox/sox/libgsm/gsm_decode.c,v 1.1 2007/09/06 16:50:55 cbagwell Exp $ */
+
+#include "private.h"
+
+#include "gsm.h"
+
+int gsm_decode (gsm s, gsm_byte * c, gsm_signal * target)
+{
+	word  	LARc[8], Nc[4], Mc[4], bc[4], xmaxc[4], xmc[13*4];
+
+#ifdef WAV49
+	if (s->wav_fmt) {
+
+		uword sr = 0;
+
+		s->frame_index = !s->frame_index;
+		if (s->frame_index) {
+
+			sr = *c++;
+			LARc[0] = sr & 0x3f;  sr >>= 6;
+			sr |= (uword)*c++ << 2;
+			LARc[1] = sr & 0x3f;  sr >>= 6;
+			sr |= (uword)*c++ << 4;
+			LARc[2] = sr & 0x1f;  sr >>= 5;
+			LARc[3] = sr & 0x1f;  sr >>= 5;
+			sr |= (uword)*c++ << 2;
+			LARc[4] = sr & 0xf;  sr >>= 4;
+			LARc[5] = sr & 0xf;  sr >>= 4;
+			sr |= (uword)*c++ << 2;			/* 5 */
+			LARc[6] = sr & 0x7;  sr >>= 3;
+			LARc[7] = sr & 0x7;  sr >>= 3;
+			sr |= (uword)*c++ << 4;
+			Nc[0] = sr & 0x7f;  sr >>= 7;
+			bc[0] = sr & 0x3;  sr >>= 2;
+			Mc[0] = sr & 0x3;  sr >>= 2;
+			sr |= (uword)*c++ << 1;
+			xmaxc[0] = sr & 0x3f;  sr >>= 6;
+			xmc[0] = sr & 0x7;  sr >>= 3;
+			sr = *c++;
+			xmc[1] = sr & 0x7;  sr >>= 3;
+			xmc[2] = sr & 0x7;  sr >>= 3;
+			sr |= (uword)*c++ << 2;
+			xmc[3] = sr & 0x7;  sr >>= 3;
+			xmc[4] = sr & 0x7;  sr >>= 3;
+			xmc[5] = sr & 0x7;  sr >>= 3;
+			sr |= (uword)*c++ << 1;			/* 10 */
+			xmc[6] = sr & 0x7;  sr >>= 3;
+			xmc[7] = sr & 0x7;  sr >>= 3;
+			xmc[8] = sr & 0x7;  sr >>= 3;
+			sr = *c++;
+			xmc[9] = sr & 0x7;  sr >>= 3;
+			xmc[10] = sr & 0x7;  sr >>= 3;
+			sr |= (uword)*c++ << 2;
+			xmc[11] = sr & 0x7;  sr >>= 3;
+			xmc[12] = sr & 0x7;  sr >>= 3;
+			sr |= (uword)*c++ << 4;
+			Nc[1] = sr & 0x7f;  sr >>= 7;
+			bc[1] = sr & 0x3;  sr >>= 2;
+			Mc[1] = sr & 0x3;  sr >>= 2;
+			sr |= (uword)*c++ << 1;
+			xmaxc[1] = sr & 0x3f;  sr >>= 6;
+			xmc[13] = sr & 0x7;  sr >>= 3;
+			sr = *c++;				/* 15 */
+			xmc[14] = sr & 0x7;  sr >>= 3;
+			xmc[15] = sr & 0x7;  sr >>= 3;
+			sr |= (uword)*c++ << 2;
+			xmc[16] = sr & 0x7;  sr >>= 3;
+			xmc[17] = sr & 0x7;  sr >>= 3;
+			xmc[18] = sr & 0x7;  sr >>= 3;
+			sr |= (uword)*c++ << 1;
+			xmc[19] = sr & 0x7;  sr >>= 3;
+			xmc[20] = sr & 0x7;  sr >>= 3;
+			xmc[21] = sr & 0x7;  sr >>= 3;
+			sr = *c++;
+			xmc[22] = sr & 0x7;  sr >>= 3;
+			xmc[23] = sr & 0x7;  sr >>= 3;
+			sr |= (uword)*c++ << 2;
+			xmc[24] = sr & 0x7;  sr >>= 3;
+			xmc[25] = sr & 0x7;  sr >>= 3;
+			sr |= (uword)*c++ << 4;			/* 20 */
+			Nc[2] = sr & 0x7f;  sr >>= 7;
+			bc[2] = sr & 0x3;  sr >>= 2;
+			Mc[2] = sr & 0x3;  sr >>= 2;
+			sr |= (uword)*c++ << 1;
+			xmaxc[2] = sr & 0x3f;  sr >>= 6;
+			xmc[26] = sr & 0x7;  sr >>= 3;
+			sr = *c++;
+			xmc[27] = sr & 0x7;  sr >>= 3;
+			xmc[28] = sr & 0x7;  sr >>= 3;
+			sr |= (uword)*c++ << 2;
+			xmc[29] = sr & 0x7;  sr >>= 3;
+			xmc[30] = sr & 0x7;  sr >>= 3;
+			xmc[31] = sr & 0x7;  sr >>= 3;
+			sr |= (uword)*c++ << 1;
+			xmc[32] = sr & 0x7;  sr >>= 3;
+			xmc[33] = sr & 0x7;  sr >>= 3;
+			xmc[34] = sr & 0x7;  sr >>= 3;
+			sr = *c++;				/* 25 */
+			xmc[35] = sr & 0x7;  sr >>= 3;
+			xmc[36] = sr & 0x7;  sr >>= 3;
+			sr |= (uword)*c++ << 2;
+			xmc[37] = sr & 0x7;  sr >>= 3;
+			xmc[38] = sr & 0x7;  sr >>= 3;
+			sr |= (uword)*c++ << 4;
+			Nc[3] = sr & 0x7f;  sr >>= 7;
+			bc[3] = sr & 0x3;  sr >>= 2;
+			Mc[3] = sr & 0x3;  sr >>= 2;
+			sr |= (uword)*c++ << 1;
+			xmaxc[3] = sr & 0x3f;  sr >>= 6;
+			xmc[39] = sr & 0x7;  sr >>= 3;
+			sr = *c++;
+			xmc[40] = sr & 0x7;  sr >>= 3;
+			xmc[41] = sr & 0x7;  sr >>= 3;
+			sr |= (uword)*c++ << 2;			/* 30 */
+			xmc[42] = sr & 0x7;  sr >>= 3;
+			xmc[43] = sr & 0x7;  sr >>= 3;
+			xmc[44] = sr & 0x7;  sr >>= 3;
+			sr |= (uword)*c++ << 1;
+			xmc[45] = sr & 0x7;  sr >>= 3;
+			xmc[46] = sr & 0x7;  sr >>= 3;
+			xmc[47] = sr & 0x7;  sr >>= 3;
+			sr = *c++;
+			xmc[48] = sr & 0x7;  sr >>= 3;
+			xmc[49] = sr & 0x7;  sr >>= 3;
+			sr |= (uword)*c++ << 2;
+			xmc[50] = sr & 0x7;  sr >>= 3;
+			xmc[51] = sr & 0x7;  sr >>= 3;
+
+			s->frame_chain = sr & 0xf;
+		}
+		else {
+			sr = s->frame_chain;
+			sr |= (uword)*c++ << 4;			/* 1 */
+			LARc[0] = sr & 0x3f;  sr >>= 6;
+			LARc[1] = sr & 0x3f;  sr >>= 6;
+			sr = *c++;
+			LARc[2] = sr & 0x1f;  sr >>= 5;
+			sr |= (uword)*c++ << 3;
+			LARc[3] = sr & 0x1f;  sr >>= 5;
+			LARc[4] = sr & 0xf;  sr >>= 4;
+			sr |= (uword)*c++ << 2;
+			LARc[5] = sr & 0xf;  sr >>= 4;
+			LARc[6] = sr & 0x7;  sr >>= 3;
+			LARc[7] = sr & 0x7;  sr >>= 3;
+			sr = *c++;				/* 5 */
+			Nc[0] = sr & 0x7f;  sr >>= 7;
+			sr |= (uword)*c++ << 1;
+			bc[0] = sr & 0x3;  sr >>= 2;
+			Mc[0] = sr & 0x3;  sr >>= 2;
+			sr |= (uword)*c++ << 5;
+			xmaxc[0] = sr & 0x3f;  sr >>= 6;
+			xmc[0] = sr & 0x7;  sr >>= 3;
+			xmc[1] = sr & 0x7;  sr >>= 3;
+			sr |= (uword)*c++ << 1;
+			xmc[2] = sr & 0x7;  sr >>= 3;
+			xmc[3] = sr & 0x7;  sr >>= 3;
+			xmc[4] = sr & 0x7;  sr >>= 3;
+			sr = *c++;
+			xmc[5] = sr & 0x7;  sr >>= 3;
+			xmc[6] = sr & 0x7;  sr >>= 3;
+			sr |= (uword)*c++ << 2;			/* 10 */
+			xmc[7] = sr & 0x7;  sr >>= 3;
+			xmc[8] = sr & 0x7;  sr >>= 3;
+			xmc[9] = sr & 0x7;  sr >>= 3;
+			sr |= (uword)*c++ << 1;
+			xmc[10] = sr & 0x7;  sr >>= 3;
+			xmc[11] = sr & 0x7;  sr >>= 3;
+			xmc[12] = sr & 0x7;  sr >>= 3;
+			sr = *c++;
+			Nc[1] = sr & 0x7f;  sr >>= 7;
+			sr |= (uword)*c++ << 1;
+			bc[1] = sr & 0x3;  sr >>= 2;
+			Mc[1] = sr & 0x3;  sr >>= 2;
+			sr |= (uword)*c++ << 5;
+			xmaxc[1] = sr & 0x3f;  sr >>= 6;
+			xmc[13] = sr & 0x7;  sr >>= 3;
+			xmc[14] = sr & 0x7;  sr >>= 3;
+			sr |= (uword)*c++ << 1;			/* 15 */
+			xmc[15] = sr & 0x7;  sr >>= 3;
+			xmc[16] = sr & 0x7;  sr >>= 3;
+			xmc[17] = sr & 0x7;  sr >>= 3;
+			sr = *c++;
+			xmc[18] = sr & 0x7;  sr >>= 3;
+			xmc[19] = sr & 0x7;  sr >>= 3;
+			sr |= (uword)*c++ << 2;
+			xmc[20] = sr & 0x7;  sr >>= 3;
+			xmc[21] = sr & 0x7;  sr >>= 3;
+			xmc[22] = sr & 0x7;  sr >>= 3;
+			sr |= (uword)*c++ << 1;
+			xmc[23] = sr & 0x7;  sr >>= 3;
+			xmc[24] = sr & 0x7;  sr >>= 3;
+			xmc[25] = sr & 0x7;  sr >>= 3;
+			sr = *c++;
+			Nc[2] = sr & 0x7f;  sr >>= 7;
+			sr |= (uword)*c++ << 1;			/* 20 */
+			bc[2] = sr & 0x3;  sr >>= 2;
+			Mc[2] = sr & 0x3;  sr >>= 2;
+			sr |= (uword)*c++ << 5;
+			xmaxc[2] = sr & 0x3f;  sr >>= 6;
+			xmc[26] = sr & 0x7;  sr >>= 3;
+			xmc[27] = sr & 0x7;  sr >>= 3;
+			sr |= (uword)*c++ << 1;	
+			xmc[28] = sr & 0x7;  sr >>= 3;
+			xmc[29] = sr & 0x7;  sr >>= 3;
+			xmc[30] = sr & 0x7;  sr >>= 3;
+			sr = *c++;
+			xmc[31] = sr & 0x7;  sr >>= 3;
+			xmc[32] = sr & 0x7;  sr >>= 3;
+			sr |= (uword)*c++ << 2;
+			xmc[33] = sr & 0x7;  sr >>= 3;
+			xmc[34] = sr & 0x7;  sr >>= 3;
+			xmc[35] = sr & 0x7;  sr >>= 3;
+			sr |= (uword)*c++ << 1;			/* 25 */
+			xmc[36] = sr & 0x7;  sr >>= 3;
+			xmc[37] = sr & 0x7;  sr >>= 3;
+			xmc[38] = sr & 0x7;  sr >>= 3;
+			sr = *c++;
+			Nc[3] = sr & 0x7f;  sr >>= 7;
+			sr |= (uword)*c++ << 1;		
+			bc[3] = sr & 0x3;  sr >>= 2;
+			Mc[3] = sr & 0x3;  sr >>= 2;
+			sr |= (uword)*c++ << 5;
+			xmaxc[3] = sr & 0x3f;  sr >>= 6;
+			xmc[39] = sr & 0x7;  sr >>= 3;
+			xmc[40] = sr & 0x7;  sr >>= 3;
+			sr |= (uword)*c++ << 1;
+			xmc[41] = sr & 0x7;  sr >>= 3;
+			xmc[42] = sr & 0x7;  sr >>= 3;
+			xmc[43] = sr & 0x7;  sr >>= 3;
+			sr = *c++;				/* 30 */
+			xmc[44] = sr & 0x7;  sr >>= 3;
+			xmc[45] = sr & 0x7;  sr >>= 3;
+			sr |= (uword)*c++ << 2;
+			xmc[46] = sr & 0x7;  sr >>= 3;
+			xmc[47] = sr & 0x7;  sr >>= 3;
+			xmc[48] = sr & 0x7;  sr >>= 3;
+			sr |= (uword)*c++ << 1;
+			xmc[49] = sr & 0x7;  sr >>= 3;
+			xmc[50] = sr & 0x7;  sr >>= 3;
+			xmc[51] = sr & 0x7;  sr >>= 3;
+		}
+	}
+	else
+#endif
+	{
+		/* GSM_MAGIC  = (*c >> 4) & 0xF; */
+
+		if (((*c >> 4) & 0x0F) != GSM_MAGIC) return -1;
+
+		LARc[0]  = (*c++ & 0xF) << 2;		/* 1 */
+		LARc[0] |= (*c >> 6) & 0x3;
+		LARc[1]  = *c++ & 0x3F;
+		LARc[2]  = (*c >> 3) & 0x1F;
+		LARc[3]  = (*c++ & 0x7) << 2;
+		LARc[3] |= (*c >> 6) & 0x3;
+		LARc[4]  = (*c >> 2) & 0xF;
+		LARc[5]  = (*c++ & 0x3) << 2;
+		LARc[5] |= (*c >> 6) & 0x3;
+		LARc[6]  = (*c >> 3) & 0x7;
+		LARc[7]  = *c++ & 0x7;
+		Nc[0]  = (*c >> 1) & 0x7F;
+		bc[0]  = (*c++ & 0x1) << 1;
+		bc[0] |= (*c >> 7) & 0x1;
+		Mc[0]  = (*c >> 5) & 0x3;
+		xmaxc[0]  = (*c++ & 0x1F) << 1;
+		xmaxc[0] |= (*c >> 7) & 0x1;
+		xmc[0]  = (*c >> 4) & 0x7;
+		xmc[1]  = (*c >> 1) & 0x7;
+		xmc[2]  = (*c++ & 0x1) << 2;
+		xmc[2] |= (*c >> 6) & 0x3;
+		xmc[3]  = (*c >> 3) & 0x7;
+		xmc[4]  = *c++ & 0x7;
+		xmc[5]  = (*c >> 5) & 0x7;
+		xmc[6]  = (*c >> 2) & 0x7;
+		xmc[7]  = (*c++ & 0x3) << 1;		/* 10 */
+		xmc[7] |= (*c >> 7) & 0x1;
+		xmc[8]  = (*c >> 4) & 0x7;
+		xmc[9]  = (*c >> 1) & 0x7;
+		xmc[10]  = (*c++ & 0x1) << 2;
+		xmc[10] |= (*c >> 6) & 0x3;
+		xmc[11]  = (*c >> 3) & 0x7;
+		xmc[12]  = *c++ & 0x7;
+		Nc[1]  = (*c >> 1) & 0x7F;
+		bc[1]  = (*c++ & 0x1) << 1;
+		bc[1] |= (*c >> 7) & 0x1;
+		Mc[1]  = (*c >> 5) & 0x3;
+		xmaxc[1]  = (*c++ & 0x1F) << 1;
+		xmaxc[1] |= (*c >> 7) & 0x1;
+		xmc[13]  = (*c >> 4) & 0x7;
+		xmc[14]  = (*c >> 1) & 0x7;
+		xmc[15]  = (*c++ & 0x1) << 2;
+		xmc[15] |= (*c >> 6) & 0x3;
+		xmc[16]  = (*c >> 3) & 0x7;
+		xmc[17]  = *c++ & 0x7;
+		xmc[18]  = (*c >> 5) & 0x7;
+		xmc[19]  = (*c >> 2) & 0x7;
+		xmc[20]  = (*c++ & 0x3) << 1;
+		xmc[20] |= (*c >> 7) & 0x1;
+		xmc[21]  = (*c >> 4) & 0x7;
+		xmc[22]  = (*c >> 1) & 0x7;
+		xmc[23]  = (*c++ & 0x1) << 2;
+		xmc[23] |= (*c >> 6) & 0x3;
+		xmc[24]  = (*c >> 3) & 0x7;
+		xmc[25]  = *c++ & 0x7;
+		Nc[2]  = (*c >> 1) & 0x7F;
+		bc[2]  = (*c++ & 0x1) << 1;		/* 20 */
+		bc[2] |= (*c >> 7) & 0x1;
+		Mc[2]  = (*c >> 5) & 0x3;
+		xmaxc[2]  = (*c++ & 0x1F) << 1;
+		xmaxc[2] |= (*c >> 7) & 0x1;
+		xmc[26]  = (*c >> 4) & 0x7;
+		xmc[27]  = (*c >> 1) & 0x7;
+		xmc[28]  = (*c++ & 0x1) << 2;
+		xmc[28] |= (*c >> 6) & 0x3;
+		xmc[29]  = (*c >> 3) & 0x7;
+		xmc[30]  = *c++ & 0x7;
+		xmc[31]  = (*c >> 5) & 0x7;
+		xmc[32]  = (*c >> 2) & 0x7;
+		xmc[33]  = (*c++ & 0x3) << 1;
+		xmc[33] |= (*c >> 7) & 0x1;
+		xmc[34]  = (*c >> 4) & 0x7;
+		xmc[35]  = (*c >> 1) & 0x7;
+		xmc[36]  = (*c++ & 0x1) << 2;
+		xmc[36] |= (*c >> 6) & 0x3;
+		xmc[37]  = (*c >> 3) & 0x7;
+		xmc[38]  = *c++ & 0x7;
+		Nc[3]  = (*c >> 1) & 0x7F;
+		bc[3]  = (*c++ & 0x1) << 1;
+		bc[3] |= (*c >> 7) & 0x1;
+		Mc[3]  = (*c >> 5) & 0x3;
+		xmaxc[3]  = (*c++ & 0x1F) << 1;
+		xmaxc[3] |= (*c >> 7) & 0x1;
+		xmc[39]  = (*c >> 4) & 0x7;
+		xmc[40]  = (*c >> 1) & 0x7;
+		xmc[41]  = (*c++ & 0x1) << 2;
+		xmc[41] |= (*c >> 6) & 0x3;
+		xmc[42]  = (*c >> 3) & 0x7;
+		xmc[43]  = *c++ & 0x7;			/* 30  */
+		xmc[44]  = (*c >> 5) & 0x7;
+		xmc[45]  = (*c >> 2) & 0x7;
+		xmc[46]  = (*c++ & 0x3) << 1;
+		xmc[46] |= (*c >> 7) & 0x1;
+		xmc[47]  = (*c >> 4) & 0x7;
+		xmc[48]  = (*c >> 1) & 0x7;
+		xmc[49]  = (*c++ & 0x1) << 2;
+		xmc[49] |= (*c >> 6) & 0x3;
+		xmc[50]  = (*c >> 3) & 0x7;
+		xmc[51]  = *c & 0x7;			/* 33 */
+	}
+
+	Gsm_Decoder(s, LARc, Nc, bc, Mc, xmaxc, xmc, target);
+
+	return 0;
+}
--- /dev/null
+++ b/libgsm/gsm_destroy.c
@@ -1,0 +1,16 @@
+/*
+ * Copyright 1992 by Jutta Degener and Carsten Bormann, Technische
+ * Universitaet Berlin.  See the accompanying file "COPYRIGHT" for
+ * details.  THERE IS ABSOLUTELY NO WARRANTY FOR THIS SOFTWARE.
+ */
+
+/* $Header: /cvsroot/sox/sox/libgsm/gsm_destroy.c,v 1.1 2007/09/06 16:50:55 cbagwell Exp $ */
+
+#include "gsm.h"
+
+#	include	<stdlib.h>
+
+void gsm_destroy (gsm S)
+{
+	if (S) free((char *)S);
+}
--- /dev/null
+++ b/libgsm/gsm_encode.c
@@ -1,0 +1,450 @@
+/*
+ * Copyright 1992 by Jutta Degener and Carsten Bormann, Technische
+ * Universitaet Berlin.  See the accompanying file "COPYRIGHT" for
+ * details.  THERE IS ABSOLUTELY NO WARRANTY FOR THIS SOFTWARE.
+ */
+
+/* $Header: /cvsroot/sox/sox/libgsm/gsm_encode.c,v 1.1 2007/09/06 16:50:55 cbagwell Exp $ */
+
+#include "private.h"
+#include "gsm.h"
+
+void gsm_encode (gsm s, gsm_signal * source, gsm_byte * c)
+{
+	word	 	LARc[8], Nc[4], Mc[4], bc[4], xmaxc[4], xmc[13*4];
+
+	Gsm_Coder(s, source, LARc, Nc, bc, Mc, xmaxc, xmc);
+
+
+	/*	variable	size
+
+		GSM_MAGIC	4
+
+		LARc[0]		6
+		LARc[1]		6
+		LARc[2]		5
+		LARc[3]		5
+		LARc[4]		4
+		LARc[5]		4
+		LARc[6]		3
+		LARc[7]		3
+
+		Nc[0]		7
+		bc[0]		2
+		Mc[0]		2
+		xmaxc[0]	6
+		xmc[0]		3
+		xmc[1]		3
+		xmc[2]		3
+		xmc[3]		3
+		xmc[4]		3
+		xmc[5]		3
+		xmc[6]		3
+		xmc[7]		3
+		xmc[8]		3
+		xmc[9]		3
+		xmc[10]		3
+		xmc[11]		3
+		xmc[12]		3
+
+		Nc[1]		7
+		bc[1]		2
+		Mc[1]		2
+		xmaxc[1]	6
+		xmc[13]		3
+		xmc[14]		3
+		xmc[15]		3
+		xmc[16]		3
+		xmc[17]		3
+		xmc[18]		3
+		xmc[19]		3
+		xmc[20]		3
+		xmc[21]		3
+		xmc[22]		3
+		xmc[23]		3
+		xmc[24]		3
+		xmc[25]		3
+
+		Nc[2]		7
+		bc[2]		2
+		Mc[2]		2
+		xmaxc[2]	6
+		xmc[26]		3
+		xmc[27]		3
+		xmc[28]		3
+		xmc[29]		3
+		xmc[30]		3
+		xmc[31]		3
+		xmc[32]		3
+		xmc[33]		3
+		xmc[34]		3
+		xmc[35]		3
+		xmc[36]		3
+		xmc[37]		3
+		xmc[38]		3
+
+		Nc[3]		7
+		bc[3]		2
+		Mc[3]		2
+		xmaxc[3]	6
+		xmc[39]		3
+		xmc[40]		3
+		xmc[41]		3
+		xmc[42]		3
+		xmc[43]		3
+		xmc[44]		3
+		xmc[45]		3
+		xmc[46]		3
+		xmc[47]		3
+		xmc[48]		3
+		xmc[49]		3
+		xmc[50]		3
+		xmc[51]		3
+	*/
+
+#ifdef WAV49
+
+	if (s->wav_fmt) {
+		s->frame_index = !s->frame_index;
+		if (s->frame_index) {
+
+			uword sr;
+
+			sr = 0;
+			sr = sr >> 6 | LARc[0] << 10;
+			sr = sr >> 6 | LARc[1] << 10;
+			*c++ = sr >> 4;
+			sr = sr >> 5 | LARc[2] << 11;
+			*c++ = sr >> 7;
+			sr = sr >> 5 | LARc[3] << 11;
+			sr = sr >> 4 | LARc[4] << 12;
+			*c++ = sr >> 6;
+			sr = sr >> 4 | LARc[5] << 12;
+			sr = sr >> 3 | LARc[6] << 13;
+			*c++ = sr >> 7;
+			sr = sr >> 3 | LARc[7] << 13;
+			sr = sr >> 7 | Nc[0] << 9;
+			*c++ = sr >> 5;
+			sr = sr >> 2 | bc[0] << 14;
+			sr = sr >> 2 | Mc[0] << 14;
+			sr = sr >> 6 | xmaxc[0] << 10;
+			*c++ = sr >> 3;
+			sr = sr >> 3 | xmc[0] << 13;
+			*c++ = sr >> 8;
+			sr = sr >> 3 | xmc[1] << 13;
+			sr = sr >> 3 | xmc[2] << 13;
+			sr = sr >> 3 | xmc[3] << 13;
+			*c++ = sr >> 7;
+			sr = sr >> 3 | xmc[4] << 13;
+			sr = sr >> 3 | xmc[5] << 13;
+			sr = sr >> 3 | xmc[6] << 13;
+			*c++ = sr >> 6;
+			sr = sr >> 3 | xmc[7] << 13;
+			sr = sr >> 3 | xmc[8] << 13;
+			*c++ = sr >> 8;
+			sr = sr >> 3 | xmc[9] << 13;
+			sr = sr >> 3 | xmc[10] << 13;
+			sr = sr >> 3 | xmc[11] << 13;
+			*c++ = sr >> 7;
+			sr = sr >> 3 | xmc[12] << 13;
+			sr = sr >> 7 | Nc[1] << 9;
+			*c++ = sr >> 5;
+			sr = sr >> 2 | bc[1] << 14;
+			sr = sr >> 2 | Mc[1] << 14;
+			sr = sr >> 6 | xmaxc[1] << 10;
+			*c++ = sr >> 3;
+			sr = sr >> 3 | xmc[13] << 13;
+			*c++ = sr >> 8;
+			sr = sr >> 3 | xmc[14] << 13;
+			sr = sr >> 3 | xmc[15] << 13;
+			sr = sr >> 3 | xmc[16] << 13;
+			*c++ = sr >> 7;
+			sr = sr >> 3 | xmc[17] << 13;
+			sr = sr >> 3 | xmc[18] << 13;
+			sr = sr >> 3 | xmc[19] << 13;
+			*c++ = sr >> 6;
+			sr = sr >> 3 | xmc[20] << 13;
+			sr = sr >> 3 | xmc[21] << 13;
+			*c++ = sr >> 8;
+			sr = sr >> 3 | xmc[22] << 13;
+			sr = sr >> 3 | xmc[23] << 13;
+			sr = sr >> 3 | xmc[24] << 13;
+			*c++ = sr >> 7;
+			sr = sr >> 3 | xmc[25] << 13;
+			sr = sr >> 7 | Nc[2] << 9;
+			*c++ = sr >> 5;
+			sr = sr >> 2 | bc[2] << 14;
+			sr = sr >> 2 | Mc[2] << 14;
+			sr = sr >> 6 | xmaxc[2] << 10;
+			*c++ = sr >> 3;
+			sr = sr >> 3 | xmc[26] << 13;
+			*c++ = sr >> 8;
+			sr = sr >> 3 | xmc[27] << 13;
+			sr = sr >> 3 | xmc[28] << 13;
+			sr = sr >> 3 | xmc[29] << 13;
+			*c++ = sr >> 7;
+			sr = sr >> 3 | xmc[30] << 13;
+			sr = sr >> 3 | xmc[31] << 13;
+			sr = sr >> 3 | xmc[32] << 13;
+			*c++ = sr >> 6;
+			sr = sr >> 3 | xmc[33] << 13;
+			sr = sr >> 3 | xmc[34] << 13;
+			*c++ = sr >> 8;
+			sr = sr >> 3 | xmc[35] << 13;
+			sr = sr >> 3 | xmc[36] << 13;
+			sr = sr >> 3 | xmc[37] << 13;
+			*c++ = sr >> 7;
+			sr = sr >> 3 | xmc[38] << 13;
+			sr = sr >> 7 | Nc[3] << 9;
+			*c++ = sr >> 5;
+			sr = sr >> 2 | bc[3] << 14;
+			sr = sr >> 2 | Mc[3] << 14;
+			sr = sr >> 6 | xmaxc[3] << 10;
+			*c++ = sr >> 3;
+			sr = sr >> 3 | xmc[39] << 13;
+			*c++ = sr >> 8;
+			sr = sr >> 3 | xmc[40] << 13;
+			sr = sr >> 3 | xmc[41] << 13;
+			sr = sr >> 3 | xmc[42] << 13;
+			*c++ = sr >> 7;
+			sr = sr >> 3 | xmc[43] << 13;
+			sr = sr >> 3 | xmc[44] << 13;
+			sr = sr >> 3 | xmc[45] << 13;
+			*c++ = sr >> 6;
+			sr = sr >> 3 | xmc[46] << 13;
+			sr = sr >> 3 | xmc[47] << 13;
+			*c++ = sr >> 8;
+			sr = sr >> 3 | xmc[48] << 13;
+			sr = sr >> 3 | xmc[49] << 13;
+			sr = sr >> 3 | xmc[50] << 13;
+			*c++ = sr >> 7;
+			sr = sr >> 3 | xmc[51] << 13;
+			sr = sr >> 4;
+			*c = sr >> 8;
+			s->frame_chain = *c;
+		}
+		else {
+			uword sr;
+
+			sr = 0;
+			sr = sr >> 4 | s->frame_chain << 12;
+			sr = sr >> 6 | LARc[0] << 10;
+			*c++ = sr >> 6;
+			sr = sr >> 6 | LARc[1] << 10;
+			*c++ = sr >> 8;
+			sr = sr >> 5 | LARc[2] << 11;
+			sr = sr >> 5 | LARc[3] << 11;
+			*c++ = sr >> 6;
+			sr = sr >> 4 | LARc[4] << 12;
+			sr = sr >> 4 | LARc[5] << 12;
+			*c++ = sr >> 6;
+			sr = sr >> 3 | LARc[6] << 13;
+			sr = sr >> 3 | LARc[7] << 13;
+			*c++ = sr >> 8;
+			sr = sr >> 7 | Nc[0] << 9;
+			sr = sr >> 2 | bc[0] << 14;
+			*c++ = sr >> 7;
+			sr = sr >> 2 | Mc[0] << 14;
+			sr = sr >> 6 | xmaxc[0] << 10;
+			*c++ = sr >> 7;
+			sr = sr >> 3 | xmc[0] << 13;
+			sr = sr >> 3 | xmc[1] << 13;
+			sr = sr >> 3 | xmc[2] << 13;
+			*c++ = sr >> 6;
+			sr = sr >> 3 | xmc[3] << 13;
+			sr = sr >> 3 | xmc[4] << 13;
+			*c++ = sr >> 8;
+			sr = sr >> 3 | xmc[5] << 13;
+			sr = sr >> 3 | xmc[6] << 13;
+			sr = sr >> 3 | xmc[7] << 13;
+			*c++ = sr >> 7;
+			sr = sr >> 3 | xmc[8] << 13;
+			sr = sr >> 3 | xmc[9] << 13;
+			sr = sr >> 3 | xmc[10] << 13;
+			*c++ = sr >> 6;
+			sr = sr >> 3 | xmc[11] << 13;
+			sr = sr >> 3 | xmc[12] << 13;
+			*c++ = sr >> 8;
+			sr = sr >> 7 | Nc[1] << 9;
+			sr = sr >> 2 | bc[1] << 14;
+			*c++ = sr >> 7;
+			sr = sr >> 2 | Mc[1] << 14;
+			sr = sr >> 6 | xmaxc[1] << 10;
+			*c++ = sr >> 7;
+			sr = sr >> 3 | xmc[13] << 13;
+			sr = sr >> 3 | xmc[14] << 13;
+			sr = sr >> 3 | xmc[15] << 13;
+			*c++ = sr >> 6;
+			sr = sr >> 3 | xmc[16] << 13;
+			sr = sr >> 3 | xmc[17] << 13;
+			*c++ = sr >> 8;
+			sr = sr >> 3 | xmc[18] << 13;
+			sr = sr >> 3 | xmc[19] << 13;
+			sr = sr >> 3 | xmc[20] << 13;
+			*c++ = sr >> 7;
+			sr = sr >> 3 | xmc[21] << 13;
+			sr = sr >> 3 | xmc[22] << 13;
+			sr = sr >> 3 | xmc[23] << 13;
+			*c++ = sr >> 6;
+			sr = sr >> 3 | xmc[24] << 13;
+			sr = sr >> 3 | xmc[25] << 13;
+			*c++ = sr >> 8;
+			sr = sr >> 7 | Nc[2] << 9;
+			sr = sr >> 2 | bc[2] << 14;
+			*c++ = sr >> 7;
+			sr = sr >> 2 | Mc[2] << 14;
+			sr = sr >> 6 | xmaxc[2] << 10;
+			*c++ = sr >> 7;
+			sr = sr >> 3 | xmc[26] << 13;
+			sr = sr >> 3 | xmc[27] << 13;
+			sr = sr >> 3 | xmc[28] << 13;
+			*c++ = sr >> 6;
+			sr = sr >> 3 | xmc[29] << 13;
+			sr = sr >> 3 | xmc[30] << 13;
+			*c++ = sr >> 8;
+			sr = sr >> 3 | xmc[31] << 13;
+			sr = sr >> 3 | xmc[32] << 13;
+			sr = sr >> 3 | xmc[33] << 13;
+			*c++ = sr >> 7;
+			sr = sr >> 3 | xmc[34] << 13;
+			sr = sr >> 3 | xmc[35] << 13;
+			sr = sr >> 3 | xmc[36] << 13;
+			*c++ = sr >> 6;
+			sr = sr >> 3 | xmc[37] << 13;
+			sr = sr >> 3 | xmc[38] << 13;
+			*c++ = sr >> 8;
+			sr = sr >> 7 | Nc[3] << 9;
+			sr = sr >> 2 | bc[3] << 14;
+			*c++ = sr >> 7;
+			sr = sr >> 2 | Mc[3] << 14;
+			sr = sr >> 6 | xmaxc[3] << 10;
+			*c++ = sr >> 7;
+			sr = sr >> 3 | xmc[39] << 13;
+			sr = sr >> 3 | xmc[40] << 13;
+			sr = sr >> 3 | xmc[41] << 13;
+			*c++ = sr >> 6;
+			sr = sr >> 3 | xmc[42] << 13;
+			sr = sr >> 3 | xmc[43] << 13;
+			*c++ = sr >> 8;
+			sr = sr >> 3 | xmc[44] << 13;
+			sr = sr >> 3 | xmc[45] << 13;
+			sr = sr >> 3 | xmc[46] << 13;
+			*c++ = sr >> 7;
+			sr = sr >> 3 | xmc[47] << 13;
+			sr = sr >> 3 | xmc[48] << 13;
+			sr = sr >> 3 | xmc[49] << 13;
+			*c++ = sr >> 6;
+			sr = sr >> 3 | xmc[50] << 13;
+			sr = sr >> 3 | xmc[51] << 13;
+			*c++ = sr >> 8;
+		}
+	}
+
+	else
+
+#endif	/* WAV49 */
+	{
+
+		*c++ =   ((GSM_MAGIC & 0xF) << 4)		/* 1 */
+		       | ((LARc[0] >> 2) & 0xF);
+		*c++ =   ((LARc[0] & 0x3) << 6)
+		       | (LARc[1] & 0x3F);
+		*c++ =   ((LARc[2] & 0x1F) << 3)
+		       | ((LARc[3] >> 2) & 0x7);
+		*c++ =   ((LARc[3] & 0x3) << 6)
+		       | ((LARc[4] & 0xF) << 2)
+		       | ((LARc[5] >> 2) & 0x3);
+		*c++ =   ((LARc[5] & 0x3) << 6)
+		       | ((LARc[6] & 0x7) << 3)
+		       | (LARc[7] & 0x7);
+		*c++ =   ((Nc[0] & 0x7F) << 1)
+		       | ((bc[0] >> 1) & 0x1);
+		*c++ =   ((bc[0] & 0x1) << 7)
+		       | ((Mc[0] & 0x3) << 5)
+		       | ((xmaxc[0] >> 1) & 0x1F);
+		*c++ =   ((xmaxc[0] & 0x1) << 7)
+		       | ((xmc[0] & 0x7) << 4)
+		       | ((xmc[1] & 0x7) << 1)
+		       | ((xmc[2] >> 2) & 0x1);
+		*c++ =   ((xmc[2] & 0x3) << 6)
+		       | ((xmc[3] & 0x7) << 3)
+		       | (xmc[4] & 0x7);
+		*c++ =   ((xmc[5] & 0x7) << 5)			/* 10 */
+		       | ((xmc[6] & 0x7) << 2)
+		       | ((xmc[7] >> 1) & 0x3);
+		*c++ =   ((xmc[7] & 0x1) << 7)
+		       | ((xmc[8] & 0x7) << 4)
+		       | ((xmc[9] & 0x7) << 1)
+		       | ((xmc[10] >> 2) & 0x1);
+		*c++ =   ((xmc[10] & 0x3) << 6)
+		       | ((xmc[11] & 0x7) << 3)
+		       | (xmc[12] & 0x7);
+		*c++ =   ((Nc[1] & 0x7F) << 1)
+		       | ((bc[1] >> 1) & 0x1);
+		*c++ =   ((bc[1] & 0x1) << 7)
+		       | ((Mc[1] & 0x3) << 5)
+		       | ((xmaxc[1] >> 1) & 0x1F);
+		*c++ =   ((xmaxc[1] & 0x1) << 7)
+		       | ((xmc[13] & 0x7) << 4)
+		       | ((xmc[14] & 0x7) << 1)
+		       | ((xmc[15] >> 2) & 0x1);
+		*c++ =   ((xmc[15] & 0x3) << 6)
+		       | ((xmc[16] & 0x7) << 3)
+		       | (xmc[17] & 0x7);
+		*c++ =   ((xmc[18] & 0x7) << 5)
+		       | ((xmc[19] & 0x7) << 2)
+		       | ((xmc[20] >> 1) & 0x3);
+		*c++ =   ((xmc[20] & 0x1) << 7)
+		       | ((xmc[21] & 0x7) << 4)
+		       | ((xmc[22] & 0x7) << 1)
+		       | ((xmc[23] >> 2) & 0x1);
+		*c++ =   ((xmc[23] & 0x3) << 6)
+		       | ((xmc[24] & 0x7) << 3)
+		       | (xmc[25] & 0x7);
+		*c++ =   ((Nc[2] & 0x7F) << 1)			/* 20 */
+		       | ((bc[2] >> 1) & 0x1);
+		*c++ =   ((bc[2] & 0x1) << 7)
+		       | ((Mc[2] & 0x3) << 5)
+		       | ((xmaxc[2] >> 1) & 0x1F);
+		*c++ =   ((xmaxc[2] & 0x1) << 7)
+		       | ((xmc[26] & 0x7) << 4)
+		       | ((xmc[27] & 0x7) << 1)
+		       | ((xmc[28] >> 2) & 0x1);
+		*c++ =   ((xmc[28] & 0x3) << 6)
+		       | ((xmc[29] & 0x7) << 3)
+		       | (xmc[30] & 0x7);
+		*c++ =   ((xmc[31] & 0x7) << 5)
+		       | ((xmc[32] & 0x7) << 2)
+		       | ((xmc[33] >> 1) & 0x3);
+		*c++ =   ((xmc[33] & 0x1) << 7)
+		       | ((xmc[34] & 0x7) << 4)
+		       | ((xmc[35] & 0x7) << 1)
+		       | ((xmc[36] >> 2) & 0x1);
+		*c++ =   ((xmc[36] & 0x3) << 6)
+		       | ((xmc[37] & 0x7) << 3)
+		       | (xmc[38] & 0x7);
+		*c++ =   ((Nc[3] & 0x7F) << 1)
+		       | ((bc[3] >> 1) & 0x1);
+		*c++ =   ((bc[3] & 0x1) << 7)
+		       | ((Mc[3] & 0x3) << 5)
+		       | ((xmaxc[3] >> 1) & 0x1F);
+		*c++ =   ((xmaxc[3] & 0x1) << 7)
+		       | ((xmc[39] & 0x7) << 4)
+		       | ((xmc[40] & 0x7) << 1)
+		       | ((xmc[41] >> 2) & 0x1);
+		*c++ =   ((xmc[41] & 0x3) << 6)			/* 30 */
+		       | ((xmc[42] & 0x7) << 3)
+		       | (xmc[43] & 0x7);
+		*c++ =   ((xmc[44] & 0x7) << 5)
+		       | ((xmc[45] & 0x7) << 2)
+		       | ((xmc[46] >> 1) & 0x3);
+		*c++ =   ((xmc[46] & 0x1) << 7)
+		       | ((xmc[47] & 0x7) << 4)
+		       | ((xmc[48] & 0x7) << 1)
+		       | ((xmc[49] >> 2) & 0x1);
+		*c++ =   ((xmc[49] & 0x3) << 6)
+		       | ((xmc[50] & 0x7) << 3)
+		       | (xmc[51] & 0x7);
+
+	}
+}
--- /dev/null
+++ b/libgsm/gsm_option.3
@@ -1,0 +1,183 @@
+.\"
+.\" Copyright 1992-1995 by Jutta Degener and Carsten Bormann, Technische
+.\" Universitaet Berlin.  See the accompanying file "COPYRIGHT" for
+.\" details.  THERE IS ABSOLUTELY NO WARRANTY FOR THIS SOFTWARE.
+.\"
+.PU
+.TH GSM_OPTION 3 
+.SH NAME
+gsm_option \(em customizing the GSM 06.10 implementation
+.SH SYNOPSIS
+#include "gsm.h"
+.PP
+int gsm_option(handle, option, valueP);
+.br
+gsm handle;
+.br
+int option;
+.br
+int * valueP;
+.SH "DESCRIPTION"
+The gsm library is an implementation of the final draft GSM 06.10
+standard for full-rate speech transcoding, a lossy
+speech compression algorithm.
+.PP
+The gsm_option() function can be used to set and query various
+options or flags that are not needed for regular GSM 06.10 encoding
+or decoding, but might be of interest in special cases.
+.PP
+The second argument to gsm_option specifies what parameter
+should be changed or queried.
+The third argument is either a null pointer, in which case
+the current value of that parameter is returned;
+or it is a pointer to an integer containing the value
+you want to set, in which case the previous value will
+be returned.
+.PP
+The following options are defined:
+.PP
+.I GSM_OPT_VERBOSE
+Verbosity level.
+.br
+.in+5
+This option is only supported if the library was compiled
+with debugging turned on, and may be used by developers of
+compression algorithms to aid debugging.
+.br
+The verbosity level can be changed at any time during encoding or decoding.
+.in-5
+.sp
+.PP
+.I GSM_OPT_FAST
+Faster compression algorithm.
+.br
+.in+5
+This implementation offers a not strictly standard-compliant, but
+faster compression algorithm that is compatible with the regular
+method and does not noticably degrade audio quality.
+.br
+The value passed to 
+.br
+.nf
+	gsm_option(handle, GSM_OPT_FAST, & value)
+.fi
+.br 
+functions as a boolean flag; if it is zero, the regular algorithm
+will be used, if not, the faster version will be used.
+.br
+The availability of this option depends on the hardware used;
+if it is not available, gsm_option will return -1 on an attempt
+to set or query it.
+.br
+This option can be set any time during encoding or decoding.
+.in-5
+.ne 5
+.sp
+.PP
+.I GSM_OPT_LTP_CUT
+Enable, disable, or query the LTP cut-off optimization.
+.br
+.in+5
+During encoding, the search for the long-term correlation
+lag forms the bottleneck of the algorithm. 
+The ltp-cut option enables an approximation that disregards most
+of the samples for purposes of finding that correlation,
+and hence speeds up the encoding at a noticable loss in quality.
+.br
+The value passed to 
+.br
+.nf
+	gsm_option(handle, GSM_OPT_LTP_CUT, & value)
+.fi
+.br 
+turns the optimization on if nonzero, and off if zero.
+.br
+This option can be set any time during encoding
+or decoding; it will only affect the encoding pass, not
+the decoding.
+.sp
+.PP
+.I GSM_OPT_WAV49
+WAV-style byte ordering.
+.br
+.in+5
+A WAV file of type #49 contains GSM 06.10-encoded frames.
+Unfortunately, the framing and code ordering of the WAV version
+are incompatible with the native ones of this GSM 06.10 library.
+The GSM_OPT_WAV49 option turns on a different packing
+algorithm that produces alternating frames of 32 and 33 bytes
+(or makes it consume alternating frames of 33 and 32 bytes, note
+the opposite order of the two numbers) which, when concatenated,
+can be used in the body of a WAV #49 frame.
+It is up to the user program to write a WAV header, if any;
+neither the library itself nor the toast program produce
+complete WAV files.
+.br
+The value passed to 
+.br
+.nf
+	gsm_option(handle, GSM_OPT_WAV49, & value)
+.fi
+.br 
+functions as a boolean flag; if it is zero, the library's native
+framing algorithm will be used, if nonzero, WAV-type packing is in effect.
+.br
+This option should be used before any frames are encoded.
+Whether or not it is supported at all depends on a
+compile-time switch, WAV49.
+Both option and compile time switch are new to the library
+as of patchlevel 9, and are considerably less tested than the
+well-worn rest of the it.
+.br
+Thanks to Jeff Chilton for the detective work and first free
+implementation of this version of the GSM 06.10 encoding.
+.sp
+.PP
+.I GSM_OPT_FRAME_CHAIN
+Query or set the chaining byte.
+.br
+.in+5
+Between the two frames of a WAV-style encoding, the GSM 06.10 library
+must keep track of one half-byte that is technically part of the first
+frame, but will be written as the first four bits of the second.
+This half-byte are the lowest four bits of the value returned by,
+and optionally set by,
+.br
+.nf
+	gsm_option(handle, GSM_OPT_FRAME_CHAIN, & value)
+.fi
+.br 
+This option can be queried and set at any time.
+.sp
+.PP
+.I GSM_OPT_FRAME_INDEX
+Query or set the current frame's index in a format's
+alternating list of frames.
+.br
+.in+5
+The WAV #49 framing uses two alternating types of frames.
+Which type the next GSM-coded frame belongs to can be queried, or,
+when decoding, announced, using
+.br
+.nf
+	gsm_option(handle, GSM_OPT_FRAME_INDEX, & value)
+.fi
+.br 
+For WAV-style framing, the value should be 0 or 1; the first frame
+of an encoding has an index of 0. 
+At library initialization, the index is set to zero.
+.br 
+The frame index can be queried and set at any time.
+Used in combination with the
+.IR GSM_OPT_FRAME_CHAIN ,
+option, it can be used to position on arbitrary GSM frames
+within a format like WAV #49 (not accounting for the lost
+internal GSM state).
+.in-5
+.SH "RETURN VALUE"
+gsm_option() returns -1 if an option is not supported, the
+previous value of the option otherwise.
+.SH BUGS
+Please direct bug reports to jutta@cs.tu-berlin.de and cabo@cs.tu-berlin.de.
+.SH "SEE ALSO"
+toast(1), gsm(3), gsm_explode(3), gsm_print(3)
--- /dev/null
+++ b/libgsm/gsm_option.c
@@ -1,0 +1,68 @@
+/*
+ * Copyright 1992 by Jutta Degener and Carsten Bormann, Technische
+ * Universitaet Berlin.  See the accompanying file "COPYRIGHT" for
+ * details.  THERE IS ABSOLUTELY NO WARRANTY FOR THIS SOFTWARE.
+ */
+
+/* $Header: /cvsroot/sox/sox/libgsm/gsm_option.c,v 1.1 2007/09/06 16:50:55 cbagwell Exp $ */
+
+#include "private.h"
+
+#include "gsm.h"
+
+int gsm_option (gsm r, int opt, int * val)
+{
+	int 	result = -1;
+
+	switch (opt) {
+	case GSM_OPT_LTP_CUT:
+#ifdef 	LTP_CUT
+		result = r->ltp_cut;
+		if (val) r->ltp_cut = *val;
+#endif
+		break;
+
+	case GSM_OPT_VERBOSE:
+#ifndef	NDEBUG
+		result = r->verbose;
+		if (val) r->verbose = *val;
+#endif
+		break;
+
+	case GSM_OPT_FAST:
+
+#if	defined(FAST) && defined(USE_FLOAT_MUL)
+		result = r->fast;
+		if (val) r->fast = !!*val;
+#endif
+		break;
+
+	case GSM_OPT_FRAME_CHAIN:
+
+#ifdef WAV49
+		result = r->frame_chain;
+		if (val) r->frame_chain = *val;
+#endif
+		break;
+
+	case GSM_OPT_FRAME_INDEX:
+
+#ifdef WAV49
+		result = r->frame_index;
+		if (val) r->frame_index = *val;
+#endif
+		break;
+
+	case GSM_OPT_WAV49:
+
+#ifdef WAV49 
+		result = r->wav_fmt;
+		if (val) r->wav_fmt = !!*val;
+#endif
+		break;
+
+	default:
+		break;
+	}
+	return result;
+}
--- /dev/null
+++ b/libgsm/long_term.c
@@ -1,0 +1,947 @@
+/*
+ * Copyright 1992 by Jutta Degener and Carsten Bormann, Technische
+ * Universitaet Berlin.  See the accompanying file "COPYRIGHT" for
+ * details.  THERE IS ABSOLUTELY NO WARRANTY FOR THIS SOFTWARE.
+ */
+
+/* $Header: /cvsroot/sox/sox/libgsm/long_term.c,v 1.1 2007/09/06 16:50:55 cbagwell Exp $ */
+
+#include <stdio.h>
+#include <assert.h>
+
+#include "private.h"
+
+#include "gsm.h"
+
+/*
+ *  4.2.11 .. 4.2.12 LONG TERM PREDICTOR (LTP) SECTION
+ */
+
+
+/*
+ * This module computes the LTP gain (bc) and the LTP lag (Nc)
+ * for the long term analysis filter.   This is done by calculating a
+ * maximum of the cross-correlation function between the current
+ * sub-segment short term residual signal d[0..39] (output of
+ * the short term analysis filter; for simplification the index
+ * of this array begins at 0 and ends at 39 for each sub-segment of the
+ * RPE-LTP analysis) and the previous reconstructed short term
+ * residual signal dp[ -120 .. -1 ].  A dynamic scaling must be
+ * performed to avoid overflow.
+ */
+
+ /* The next procedure exists in six versions.  First two integer
+  * version (if USE_FLOAT_MUL is not defined); then four floating
+  * point versions, twice with proper scaling (USE_FLOAT_MUL defined),
+  * once without (USE_FLOAT_MUL and FAST defined, and fast run-time
+  * option used).  Every pair has first a Cut version (see the -C
+  * option to toast or the LTP_CUT option to gsm_option()), then the
+  * uncut one.  (For a detailed explanation of why this is altogether
+  * a bad idea, see Henry Spencer and Geoff Collyer, ``#ifdef Considered
+  * Harmful''.)
+  */
+
+#ifndef  USE_FLOAT_MUL
+
+#ifdef	LTP_CUT
+
+static void Cut_Calculation_of_the_LTP_parameters (
+
+	struct gsm_state * st,
+
+	register word	* d,		/* [0..39]	IN	*/
+	register word	* dp,		/* [-120..-1]	IN	*/
+	word		* bc_out,	/* 		OUT	*/
+	word		* Nc_out	/* 		OUT	*/
+)
+{
+	register int  	k, lambda;
+	word		Nc, bc;
+	word		wt[40];
+
+	longword	L_result;
+	longword	L_max, L_power;
+	word		R, S, dmax, scal, best_k;
+	word		ltp_cut;
+
+	register word	temp, wt_k;
+
+	/*  Search of the optimum scaling of d[0..39].
+	 */
+	dmax = 0;
+	for (k = 0; k <= 39; k++) {
+		temp = d[k];
+		temp = GSM_ABS( temp );
+		if (temp > dmax) {
+			dmax = temp;
+			best_k = k;
+		}
+	}
+	temp = 0;
+	if (dmax == 0) scal = 0;
+	else {
+		assert(dmax > 0);
+		temp = gsm_norm( (longword)dmax << 16 );
+	}
+	if (temp > 6) scal = 0;
+	else scal = 6 - temp;
+	assert(scal >= 0);
+
+	/* Search for the maximum cross-correlation and coding of the LTP lag
+	 */
+	L_max = 0;
+	Nc    = 40;	/* index for the maximum cross-correlation */
+	wt_k  = SASR(d[best_k], scal);
+
+	for (lambda = 40; lambda <= 120; lambda++) {
+		L_result = (longword)wt_k * dp[best_k - lambda];
+		if (L_result > L_max) {
+			Nc    = lambda;
+			L_max = L_result;
+		}
+	}
+	*Nc_out = Nc;
+	L_max <<= 1;
+
+	/*  Rescaling of L_max
+	 */
+	assert(scal <= 100 && scal >= -100);
+	L_max = L_max >> (6 - scal);	/* sub(6, scal) */
+
+	assert( Nc <= 120 && Nc >= 40);
+
+	/*   Compute the power of the reconstructed short term residual
+	 *   signal dp[..]
+	 */
+	L_power = 0;
+	for (k = 0; k <= 39; k++) {
+
+		register longword L_temp;
+
+		L_temp   = SASR( dp[k - Nc], 3 );
+		L_power += L_temp * L_temp;
+	}
+	L_power <<= 1;	/* from L_MULT */
+
+	/*  Normalization of L_max and L_power
+	 */
+
+	if (L_max <= 0)  {
+		*bc_out = 0;
+		return;
+	}
+	if (L_max >= L_power) {
+		*bc_out = 3;
+		return;
+	}
+
+	temp = gsm_norm( L_power );
+
+	R = SASR( L_max   << temp, 16 );
+	S = SASR( L_power << temp, 16 );
+
+	/*  Coding of the LTP gain
+	 */
+
+	/*  Table 4.3a must be used to obtain the level DLB[i] for the
+	 *  quantization of the LTP gain b to get the coded version bc.
+	 */
+	for (bc = 0; bc <= 2; bc++) if (R <= gsm_mult(S, gsm_DLB[bc])) break;
+	*bc_out = bc;
+}
+
+#endif 	/* LTP_CUT */
+
+static void Calculation_of_the_LTP_parameters (
+	register word	* d,		/* [0..39]	IN	*/
+	register word	* dp,		/* [-120..-1]	IN	*/
+	word		* bc_out,	/* 		OUT	*/
+	word		* Nc_out	/* 		OUT	*/
+)
+{
+	register int  	k, lambda;
+	word		Nc, bc;
+	word		wt[40];
+
+	longword	L_max, L_power;
+	word		R, S, dmax, scal;
+	register word	temp;
+
+	/*  Search of the optimum scaling of d[0..39].
+	 */
+	dmax = 0;
+
+	for (k = 0; k <= 39; k++) {
+		temp = d[k];
+		temp = GSM_ABS( temp );
+		if (temp > dmax) dmax = temp;
+	}
+
+	temp = 0;
+	if (dmax == 0) scal = 0;
+	else {
+		assert(dmax > 0);
+		temp = gsm_norm( (longword)dmax << 16 );
+	}
+
+	if (temp > 6) scal = 0;
+	else scal = 6 - temp;
+
+	assert(scal >= 0);
+
+	/*  Initialization of a working array wt
+	 */
+
+	for (k = 0; k <= 39; k++) wt[k] = SASR( d[k], scal );
+
+	/* Search for the maximum cross-correlation and coding of the LTP lag
+	 */
+	L_max = 0;
+	Nc    = 40;	/* index for the maximum cross-correlation */
+
+	for (lambda = 40; lambda <= 120; lambda++) {
+
+# undef STEP
+#		define STEP(k) 	(longword)wt[k] * dp[k - lambda]
+
+		register longword L_result;
+
+		L_result  = STEP(0)  ; L_result += STEP(1) ;
+		L_result += STEP(2)  ; L_result += STEP(3) ;
+		L_result += STEP(4)  ; L_result += STEP(5)  ;
+		L_result += STEP(6)  ; L_result += STEP(7)  ;
+		L_result += STEP(8)  ; L_result += STEP(9)  ;
+		L_result += STEP(10) ; L_result += STEP(11) ;
+		L_result += STEP(12) ; L_result += STEP(13) ;
+		L_result += STEP(14) ; L_result += STEP(15) ;
+		L_result += STEP(16) ; L_result += STEP(17) ;
+		L_result += STEP(18) ; L_result += STEP(19) ;
+		L_result += STEP(20) ; L_result += STEP(21) ;
+		L_result += STEP(22) ; L_result += STEP(23) ;
+		L_result += STEP(24) ; L_result += STEP(25) ;
+		L_result += STEP(26) ; L_result += STEP(27) ;
+		L_result += STEP(28) ; L_result += STEP(29) ;
+		L_result += STEP(30) ; L_result += STEP(31) ;
+		L_result += STEP(32) ; L_result += STEP(33) ;
+		L_result += STEP(34) ; L_result += STEP(35) ;
+		L_result += STEP(36) ; L_result += STEP(37) ;
+		L_result += STEP(38) ; L_result += STEP(39) ;
+
+		if (L_result > L_max) {
+
+			Nc    = lambda;
+			L_max = L_result;
+		}
+	}
+
+	*Nc_out = Nc;
+
+	L_max <<= 1;
+
+	/*  Rescaling of L_max
+	 */
+	assert(scal <= 100 && scal >=  -100);
+	L_max = L_max >> (6 - scal);	/* sub(6, scal) */
+
+	assert( Nc <= 120 && Nc >= 40);
+
+	/*   Compute the power of the reconstructed short term residual
+	 *   signal dp[..]
+	 */
+	L_power = 0;
+	for (k = 0; k <= 39; k++) {
+
+		register longword L_temp;
+
+		L_temp   = SASR( dp[k - Nc], 3 );
+		L_power += L_temp * L_temp;
+	}
+	L_power <<= 1;	/* from L_MULT */
+
+	/*  Normalization of L_max and L_power
+	 */
+
+	if (L_max <= 0)  {
+		*bc_out = 0;
+		return;
+	}
+	if (L_max >= L_power) {
+		*bc_out = 3;
+		return;
+	}
+
+	temp = gsm_norm( L_power );
+
+	R = SASR( L_max   << temp, 16 );
+	S = SASR( L_power << temp, 16 );
+
+	/*  Coding of the LTP gain
+	 */
+
+	/*  Table 4.3a must be used to obtain the level DLB[i] for the
+	 *  quantization of the LTP gain b to get the coded version bc.
+	 */
+	for (bc = 0; bc <= 2; bc++) if (R <= gsm_mult(S, gsm_DLB[bc])) break;
+	*bc_out = bc;
+}
+
+#else	/* USE_FLOAT_MUL */
+
+#ifdef	LTP_CUT
+
+static void Cut_Calculation_of_the_LTP_parameters (
+	struct gsm_state * st,		/*              IN 	*/
+	register word	* d,		/* [0..39]	IN	*/
+	register word	* dp,		/* [-120..-1]	IN	*/
+	word		* bc_out,	/* 		OUT	*/
+	word		* Nc_out	/* 		OUT	*/
+)
+{
+	register int  	k, lambda;
+	word		Nc, bc;
+	word		ltp_cut;
+
+	float		wt_float[40];
+	float		dp_float_base[120], * dp_float = dp_float_base + 120;
+
+	longword	L_max, L_power;
+	word		R, S, dmax, scal;
+	register word	temp;
+
+	/*  Search of the optimum scaling of d[0..39].
+	 */
+	dmax = 0;
+
+	for (k = 0; k <= 39; k++) {
+		temp = d[k];
+		temp = GSM_ABS( temp );
+		if (temp > dmax) dmax = temp;
+	}
+
+	temp = 0;
+	if (dmax == 0) scal = 0;
+	else {
+		assert(dmax > 0);
+		temp = gsm_norm( (longword)dmax << 16 );
+	}
+
+	if (temp > 6) scal = 0;
+	else scal = 6 - temp;
+
+	assert(scal >= 0);
+	ltp_cut = (longword)SASR(dmax, scal) * st->ltp_cut / 100; 
+
+
+	/*  Initialization of a working array wt
+	 */
+
+	for (k = 0; k < 40; k++) {
+		register word w = SASR( d[k], scal );
+		if (w < 0 ? w > -ltp_cut : w < ltp_cut) {
+			wt_float[k] = 0.0;
+		}
+		else {
+			wt_float[k] =  w;
+		}
+	}
+	for (k = -120; k <  0; k++) dp_float[k] =  dp[k];
+
+	/* Search for the maximum cross-correlation and coding of the LTP lag
+	 */
+	L_max = 0;
+	Nc    = 40;	/* index for the maximum cross-correlation */
+
+	for (lambda = 40; lambda <= 120; lambda += 9) {
+
+		/*  Calculate L_result for l = lambda .. lambda + 9.
+		 */
+		register float *lp = dp_float - lambda;
+
+		register float	W;
+		register float	a = lp[-8], b = lp[-7], c = lp[-6],
+				d = lp[-5], e = lp[-4], f = lp[-3],
+				g = lp[-2], h = lp[-1];
+		register float  E; 
+		register float  S0 = 0, S1 = 0, S2 = 0, S3 = 0, S4 = 0,
+				S5 = 0, S6 = 0, S7 = 0, S8 = 0;
+
+#		undef STEP
+#		define	STEP(K, a, b, c, d, e, f, g, h) \
+			if ((W = wt_float[K]) != 0.0) {	\
+			E = W * a; S8 += E;		\
+			E = W * b; S7 += E;		\
+			E = W * c; S6 += E;		\
+			E = W * d; S5 += E;		\
+			E = W * e; S4 += E;		\
+			E = W * f; S3 += E;		\
+			E = W * g; S2 += E;		\
+			E = W * h; S1 += E;		\
+			a  = lp[K];			\
+			E = W * a; S0 += E; } else (a = lp[K])
+
+#		define	STEP_A(K)	STEP(K, a, b, c, d, e, f, g, h)
+#		define	STEP_B(K)	STEP(K, b, c, d, e, f, g, h, a)
+#		define	STEP_C(K)	STEP(K, c, d, e, f, g, h, a, b)
+#		define	STEP_D(K)	STEP(K, d, e, f, g, h, a, b, c)
+#		define	STEP_E(K)	STEP(K, e, f, g, h, a, b, c, d)
+#		define	STEP_F(K)	STEP(K, f, g, h, a, b, c, d, e)
+#		define	STEP_G(K)	STEP(K, g, h, a, b, c, d, e, f)
+#		define	STEP_H(K)	STEP(K, h, a, b, c, d, e, f, g)
+
+		STEP_A( 0); STEP_B( 1); STEP_C( 2); STEP_D( 3);
+		STEP_E( 4); STEP_F( 5); STEP_G( 6); STEP_H( 7);
+
+		STEP_A( 8); STEP_B( 9); STEP_C(10); STEP_D(11);
+		STEP_E(12); STEP_F(13); STEP_G(14); STEP_H(15);
+
+		STEP_A(16); STEP_B(17); STEP_C(18); STEP_D(19);
+		STEP_E(20); STEP_F(21); STEP_G(22); STEP_H(23);
+
+		STEP_A(24); STEP_B(25); STEP_C(26); STEP_D(27);
+		STEP_E(28); STEP_F(29); STEP_G(30); STEP_H(31);
+
+		STEP_A(32); STEP_B(33); STEP_C(34); STEP_D(35);
+		STEP_E(36); STEP_F(37); STEP_G(38); STEP_H(39);
+
+		if (S0 > L_max) { L_max = S0; Nc = lambda;     }
+		if (S1 > L_max) { L_max = S1; Nc = lambda + 1; }
+		if (S2 > L_max) { L_max = S2; Nc = lambda + 2; }
+		if (S3 > L_max) { L_max = S3; Nc = lambda + 3; }
+		if (S4 > L_max) { L_max = S4; Nc = lambda + 4; }
+		if (S5 > L_max) { L_max = S5; Nc = lambda + 5; }
+		if (S6 > L_max) { L_max = S6; Nc = lambda + 6; }
+		if (S7 > L_max) { L_max = S7; Nc = lambda + 7; }
+		if (S8 > L_max) { L_max = S8; Nc = lambda + 8; }
+
+	}
+	*Nc_out = Nc;
+
+	L_max <<= 1;
+
+	/*  Rescaling of L_max
+	 */
+	assert(scal <= 100 && scal >=  -100);
+	L_max = L_max >> (6 - scal);	/* sub(6, scal) */
+
+	assert( Nc <= 120 && Nc >= 40);
+
+	/*   Compute the power of the reconstructed short term residual
+	 *   signal dp[..]
+	 */
+	L_power = 0;
+	for (k = 0; k <= 39; k++) {
+
+		register longword L_temp;
+
+		L_temp   = SASR( dp[k - Nc], 3 );
+		L_power += L_temp * L_temp;
+	}
+	L_power <<= 1;	/* from L_MULT */
+
+	/*  Normalization of L_max and L_power
+	 */
+
+	if (L_max <= 0)  {
+		*bc_out = 0;
+		return;
+	}
+	if (L_max >= L_power) {
+		*bc_out = 3;
+		return;
+	}
+
+	temp = gsm_norm( L_power );
+
+	R = SASR( L_max   << temp, 16 );
+	S = SASR( L_power << temp, 16 );
+
+	/*  Coding of the LTP gain
+	 */
+
+	/*  Table 4.3a must be used to obtain the level DLB[i] for the
+	 *  quantization of the LTP gain b to get the coded version bc.
+	 */
+	for (bc = 0; bc <= 2; bc++) if (R <= gsm_mult(S, gsm_DLB[bc])) break;
+	*bc_out = bc;
+}
+
+#endif /* LTP_CUT */
+
+static void Calculation_of_the_LTP_parameters (
+	register word	* d,		/* [0..39]	IN	*/
+	register word	* dp,		/* [-120..-1]	IN	*/
+	word		* bc_out,	/* 		OUT	*/
+	word		* Nc_out	/* 		OUT	*/
+)
+{
+	register int  	k, lambda;
+	word		Nc, bc;
+
+	float		wt_float[40];
+	float		dp_float_base[120], * dp_float = dp_float_base + 120;
+
+	longword	L_max, L_power;
+	word		R, S, dmax, scal;
+	register word	temp;
+
+	/*  Search of the optimum scaling of d[0..39].
+	 */
+	dmax = 0;
+
+	for (k = 0; k <= 39; k++) {
+		temp = d[k];
+		temp = GSM_ABS( temp );
+		if (temp > dmax) dmax = temp;
+	}
+
+	temp = 0;
+	if (dmax == 0) scal = 0;
+	else {
+		assert(dmax > 0);
+		temp = gsm_norm( (longword)dmax << 16 );
+	}
+
+	if (temp > 6) scal = 0;
+	else scal = 6 - temp;
+
+	assert(scal >= 0);
+
+	/*  Initialization of a working array wt
+	 */
+
+	for (k =    0; k < 40; k++) wt_float[k] =  SASR( d[k], scal );
+	for (k = -120; k <  0; k++) dp_float[k] =  dp[k];
+
+	/* Search for the maximum cross-correlation and coding of the LTP lag
+	 */
+	L_max = 0;
+	Nc    = 40;	/* index for the maximum cross-correlation */
+
+	for (lambda = 40; lambda <= 120; lambda += 9) {
+
+		/*  Calculate L_result for l = lambda .. lambda + 9.
+		 */
+		register float *lp = dp_float - lambda;
+
+		register float	W;
+		register float	a = lp[-8], b = lp[-7], c = lp[-6],
+				d = lp[-5], e = lp[-4], f = lp[-3],
+				g = lp[-2], h = lp[-1];
+		register float  E; 
+		register float  S0 = 0, S1 = 0, S2 = 0, S3 = 0, S4 = 0,
+				S5 = 0, S6 = 0, S7 = 0, S8 = 0;
+
+#		undef STEP
+#		define	STEP(K, a, b, c, d, e, f, g, h) \
+			W = wt_float[K];		\
+			E = W * a; S8 += E;		\
+			E = W * b; S7 += E;		\
+			E = W * c; S6 += E;		\
+			E = W * d; S5 += E;		\
+			E = W * e; S4 += E;		\
+			E = W * f; S3 += E;		\
+			E = W * g; S2 += E;		\
+			E = W * h; S1 += E;		\
+			a  = lp[K];			\
+			E = W * a; S0 += E
+
+#		define	STEP_A(K)	STEP(K, a, b, c, d, e, f, g, h)
+#		define	STEP_B(K)	STEP(K, b, c, d, e, f, g, h, a)
+#		define	STEP_C(K)	STEP(K, c, d, e, f, g, h, a, b)
+#		define	STEP_D(K)	STEP(K, d, e, f, g, h, a, b, c)
+#		define	STEP_E(K)	STEP(K, e, f, g, h, a, b, c, d)
+#		define	STEP_F(K)	STEP(K, f, g, h, a, b, c, d, e)
+#		define	STEP_G(K)	STEP(K, g, h, a, b, c, d, e, f)
+#		define	STEP_H(K)	STEP(K, h, a, b, c, d, e, f, g)
+
+		STEP_A( 0); STEP_B( 1); STEP_C( 2); STEP_D( 3);
+		STEP_E( 4); STEP_F( 5); STEP_G( 6); STEP_H( 7);
+
+		STEP_A( 8); STEP_B( 9); STEP_C(10); STEP_D(11);
+		STEP_E(12); STEP_F(13); STEP_G(14); STEP_H(15);
+
+		STEP_A(16); STEP_B(17); STEP_C(18); STEP_D(19);
+		STEP_E(20); STEP_F(21); STEP_G(22); STEP_H(23);
+
+		STEP_A(24); STEP_B(25); STEP_C(26); STEP_D(27);
+		STEP_E(28); STEP_F(29); STEP_G(30); STEP_H(31);
+
+		STEP_A(32); STEP_B(33); STEP_C(34); STEP_D(35);
+		STEP_E(36); STEP_F(37); STEP_G(38); STEP_H(39);
+
+		if (S0 > L_max) { L_max = S0; Nc = lambda;     }
+		if (S1 > L_max) { L_max = S1; Nc = lambda + 1; }
+		if (S2 > L_max) { L_max = S2; Nc = lambda + 2; }
+		if (S3 > L_max) { L_max = S3; Nc = lambda + 3; }
+		if (S4 > L_max) { L_max = S4; Nc = lambda + 4; }
+		if (S5 > L_max) { L_max = S5; Nc = lambda + 5; }
+		if (S6 > L_max) { L_max = S6; Nc = lambda + 6; }
+		if (S7 > L_max) { L_max = S7; Nc = lambda + 7; }
+		if (S8 > L_max) { L_max = S8; Nc = lambda + 8; }
+	}
+	*Nc_out = Nc;
+
+	L_max <<= 1;
+
+	/*  Rescaling of L_max
+	 */
+	assert(scal <= 100 && scal >=  -100);
+	L_max = L_max >> (6 - scal);	/* sub(6, scal) */
+
+	assert( Nc <= 120 && Nc >= 40);
+
+	/*   Compute the power of the reconstructed short term residual
+	 *   signal dp[..]
+	 */
+	L_power = 0;
+	for (k = 0; k <= 39; k++) {
+
+		register longword L_temp;
+
+		L_temp   = SASR( dp[k - Nc], 3 );
+		L_power += L_temp * L_temp;
+	}
+	L_power <<= 1;	/* from L_MULT */
+
+	/*  Normalization of L_max and L_power
+	 */
+
+	if (L_max <= 0)  {
+		*bc_out = 0;
+		return;
+	}
+	if (L_max >= L_power) {
+		*bc_out = 3;
+		return;
+	}
+
+	temp = gsm_norm( L_power );
+
+	R = SASR( L_max   << temp, 16 );
+	S = SASR( L_power << temp, 16 );
+
+	/*  Coding of the LTP gain
+	 */
+
+	/*  Table 4.3a must be used to obtain the level DLB[i] for the
+	 *  quantization of the LTP gain b to get the coded version bc.
+	 */
+	for (bc = 0; bc <= 2; bc++) if (R <= gsm_mult(S, gsm_DLB[bc])) break;
+	*bc_out = bc;
+}
+
+#ifdef	FAST
+#ifdef	LTP_CUT
+
+static void Cut_Fast_Calculation_of_the_LTP_parameters (
+	struct gsm_state * st,		/*              IN	*/
+	register word	* d,		/* [0..39]	IN	*/
+	register word	* dp,		/* [-120..-1]	IN	*/
+	word		* bc_out,	/* 		OUT	*/
+	word		* Nc_out	/* 		OUT	*/
+)
+{
+	register int  	k, lambda;
+	register float	wt_float;
+	word		Nc, bc;
+	word		wt_max, best_k, ltp_cut;
+
+	float		dp_float_base[120], * dp_float = dp_float_base + 120;
+
+	register float	L_result, L_max, L_power;
+
+	wt_max = 0;
+
+	for (k = 0; k < 40; ++k) {
+		if      ( d[k] > wt_max) wt_max =  d[best_k = k];
+		else if (-d[k] > wt_max) wt_max = -d[best_k = k];
+	}
+
+	assert(wt_max >= 0);
+	wt_float = (float)wt_max;
+
+	for (k = -120; k < 0; ++k) dp_float[k] = (float)dp[k];
+
+	/* Search for the maximum cross-correlation and coding of the LTP lag
+	 */
+	L_max = 0;
+	Nc    = 40;	/* index for the maximum cross-correlation */
+
+	for (lambda = 40; lambda <= 120; lambda++) {
+		L_result = wt_float * dp_float[best_k - lambda];
+		if (L_result > L_max) {
+			Nc    = lambda;
+			L_max = L_result;
+		}
+	}
+
+	*Nc_out = Nc;
+	if (L_max <= 0.)  {
+		*bc_out = 0;
+		return;
+	}
+
+	/*  Compute the power of the reconstructed short term residual
+	 *  signal dp[..]
+	 */
+	dp_float -= Nc;
+	L_power = 0;
+	for (k = 0; k < 40; ++k) {
+		register float f = dp_float[k];
+		L_power += f * f;
+	}
+
+	if (L_max >= L_power) {
+		*bc_out = 3;
+		return;
+	}
+
+	/*  Coding of the LTP gain
+	 *  Table 4.3a must be used to obtain the level DLB[i] for the
+	 *  quantization of the LTP gain b to get the coded version bc.
+	 */
+	lambda = L_max / L_power * 32768.;
+	for (bc = 0; bc <= 2; ++bc) if (lambda <= gsm_DLB[bc]) break;
+	*bc_out = bc;
+}
+
+#endif /* LTP_CUT */
+
+static void Fast_Calculation_of_the_LTP_parameters (
+	register word	* d,		/* [0..39]	IN	*/
+	register word	* dp,		/* [-120..-1]	IN	*/
+	word		* bc_out,	/* 		OUT	*/
+	word		* Nc_out	/* 		OUT	*/
+)
+{
+	register int  	k, lambda;
+	word		Nc, bc;
+
+	float		wt_float[40];
+	float		dp_float_base[120], * dp_float = dp_float_base + 120;
+
+	register float	L_max, L_power;
+
+	for (k = 0; k < 40; ++k) wt_float[k] = (float)d[k];
+	for (k = -120; k < 0; ++k) dp_float[k] = (float)dp[k];
+
+	/* Search for the maximum cross-correlation and coding of the LTP lag
+	 */
+	L_max = 0;
+	Nc    = 40;	/* index for the maximum cross-correlation */
+
+	for (lambda = 40; lambda <= 120; lambda += 9) {
+
+		/*  Calculate L_result for l = lambda .. lambda + 9.
+		 */
+		register float *lp = dp_float - lambda;
+
+		register float	W;
+		register float	a = lp[-8], b = lp[-7], c = lp[-6],
+				d = lp[-5], e = lp[-4], f = lp[-3],
+				g = lp[-2], h = lp[-1];
+		register float  E; 
+		register float  S0 = 0, S1 = 0, S2 = 0, S3 = 0, S4 = 0,
+				S5 = 0, S6 = 0, S7 = 0, S8 = 0;
+
+#		undef STEP
+#		define	STEP(K, a, b, c, d, e, f, g, h) \
+			W = wt_float[K];		\
+			E = W * a; S8 += E;		\
+			E = W * b; S7 += E;		\
+			E = W * c; S6 += E;		\
+			E = W * d; S5 += E;		\
+			E = W * e; S4 += E;		\
+			E = W * f; S3 += E;		\
+			E = W * g; S2 += E;		\
+			E = W * h; S1 += E;		\
+			a  = lp[K];			\
+			E = W * a; S0 += E
+
+#		define	STEP_A(K)	STEP(K, a, b, c, d, e, f, g, h)
+#		define	STEP_B(K)	STEP(K, b, c, d, e, f, g, h, a)
+#		define	STEP_C(K)	STEP(K, c, d, e, f, g, h, a, b)
+#		define	STEP_D(K)	STEP(K, d, e, f, g, h, a, b, c)
+#		define	STEP_E(K)	STEP(K, e, f, g, h, a, b, c, d)
+#		define	STEP_F(K)	STEP(K, f, g, h, a, b, c, d, e)
+#		define	STEP_G(K)	STEP(K, g, h, a, b, c, d, e, f)
+#		define	STEP_H(K)	STEP(K, h, a, b, c, d, e, f, g)
+
+		STEP_A( 0); STEP_B( 1); STEP_C( 2); STEP_D( 3);
+		STEP_E( 4); STEP_F( 5); STEP_G( 6); STEP_H( 7);
+
+		STEP_A( 8); STEP_B( 9); STEP_C(10); STEP_D(11);
+		STEP_E(12); STEP_F(13); STEP_G(14); STEP_H(15);
+
+		STEP_A(16); STEP_B(17); STEP_C(18); STEP_D(19);
+		STEP_E(20); STEP_F(21); STEP_G(22); STEP_H(23);
+
+		STEP_A(24); STEP_B(25); STEP_C(26); STEP_D(27);
+		STEP_E(28); STEP_F(29); STEP_G(30); STEP_H(31);
+
+		STEP_A(32); STEP_B(33); STEP_C(34); STEP_D(35);
+		STEP_E(36); STEP_F(37); STEP_G(38); STEP_H(39);
+
+		if (S0 > L_max) { L_max = S0; Nc = lambda;     }
+		if (S1 > L_max) { L_max = S1; Nc = lambda + 1; }
+		if (S2 > L_max) { L_max = S2; Nc = lambda + 2; }
+		if (S3 > L_max) { L_max = S3; Nc = lambda + 3; }
+		if (S4 > L_max) { L_max = S4; Nc = lambda + 4; }
+		if (S5 > L_max) { L_max = S5; Nc = lambda + 5; }
+		if (S6 > L_max) { L_max = S6; Nc = lambda + 6; }
+		if (S7 > L_max) { L_max = S7; Nc = lambda + 7; }
+		if (S8 > L_max) { L_max = S8; Nc = lambda + 8; }
+	}
+	*Nc_out = Nc;
+
+	if (L_max <= 0.)  {
+		*bc_out = 0;
+		return;
+	}
+
+	/*  Compute the power of the reconstructed short term residual
+	 *  signal dp[..]
+	 */
+	dp_float -= Nc;
+	L_power = 0;
+	for (k = 0; k < 40; ++k) {
+		register float f = dp_float[k];
+		L_power += f * f;
+	}
+
+	if (L_max >= L_power) {
+		*bc_out = 3;
+		return;
+	}
+
+	/*  Coding of the LTP gain
+	 *  Table 4.3a must be used to obtain the level DLB[i] for the
+	 *  quantization of the LTP gain b to get the coded version bc.
+	 */
+	lambda = L_max / L_power * 32768.;
+	for (bc = 0; bc <= 2; ++bc) if (lambda <= gsm_DLB[bc]) break;
+	*bc_out = bc;
+}
+
+#endif	/* FAST 	 */
+#endif	/* USE_FLOAT_MUL */
+
+
+/* 4.2.12 */
+
+static void Long_term_analysis_filtering (
+	word		bc,	/* 					IN  */
+	word		Nc,	/* 					IN  */
+	register word	* dp,	/* previous d	[-120..-1]		IN  */
+	register word	* d,	/* d		[0..39]			IN  */
+	register word	* dpp,	/* estimate	[0..39]			OUT */
+	register word	* e	/* long term res. signal [0..39]	OUT */
+)
+/*
+ *  In this part, we have to decode the bc parameter to compute
+ *  the samples of the estimate dpp[0..39].  The decoding of bc needs the
+ *  use of table 4.3b.  The long term residual signal e[0..39]
+ *  is then calculated to be fed to the RPE encoding section.
+ */
+{
+	register int      k;
+	register longword ltmp;
+
+#	undef STEP
+#	define STEP(BP)					\
+	for (k = 0; k <= 39; k++) {			\
+		dpp[k]  = GSM_MULT_R( BP, dp[k - Nc]);	\
+		e[k]	= GSM_SUB( d[k], dpp[k] );	\
+	}
+
+	switch (bc) {
+	case 0:	STEP(  3277 ); break;
+	case 1:	STEP( 11469 ); break;
+	case 2: STEP( 21299 ); break;
+	case 3: STEP( 32767 ); break; 
+	}
+}
+
+void Gsm_Long_Term_Predictor ( 	/* 4x for 160 samples */
+
+	struct gsm_state	* S,
+
+	word	* d,	/* [0..39]   residual signal	IN	*/
+	word	* dp,	/* [-120..-1] d'		IN	*/
+
+	word	* e,	/* [0..39] 			OUT	*/
+	word	* dpp,	/* [0..39] 			OUT	*/
+	word	* Nc,	/* correlation lag		OUT	*/
+	word	* bc	/* gain factor			OUT	*/
+)
+{
+	assert( d  ); assert( dp ); assert( e  );
+	assert( dpp); assert( Nc ); assert( bc );
+
+#if defined(FAST) && defined(USE_FLOAT_MUL)
+	if (S->fast) 
+#if   defined (LTP_CUT)
+		if (S->ltp_cut)
+			Cut_Fast_Calculation_of_the_LTP_parameters(S,
+				d, dp, bc, Nc);
+		else
+#endif /* LTP_CUT */
+			Fast_Calculation_of_the_LTP_parameters(d, dp, bc, Nc );
+	else 
+#endif /* FAST & USE_FLOAT_MUL */
+#ifdef LTP_CUT
+		if (S->ltp_cut)
+			Cut_Calculation_of_the_LTP_parameters(S, d, dp, bc, Nc);
+		else
+#endif
+			Calculation_of_the_LTP_parameters(d, dp, bc, Nc);
+
+	Long_term_analysis_filtering( *bc, *Nc, dp, d, dpp, e );
+}
+
+/* 4.3.2 */
+void Gsm_Long_Term_Synthesis_Filtering (
+	struct gsm_state	* S,
+
+	word			Ncr,
+	word			bcr,
+	register word		* erp,	   /* [0..39]		  	 IN */
+	register word		* drp	   /* [-120..-1] IN, [-120..40] OUT */
+)
+/*
+ *  This procedure uses the bcr and Ncr parameter to realize the
+ *  long term synthesis filtering.  The decoding of bcr needs
+ *  table 4.3b.
+ */
+{
+	register longword	ltmp;	/* for ADD */
+	register int 		k;
+	word			brp, drpp, Nr;
+
+	/*  Check the limits of Nr.
+	 */
+	Nr = Ncr < 40 || Ncr > 120 ? S->nrp : Ncr;
+	S->nrp = Nr;
+	assert(Nr >= 40 && Nr <= 120);
+
+	/*  Decoding of the LTP gain bcr
+	 */
+	brp = gsm_QLB[ bcr ];
+
+	/*  Computation of the reconstructed short term residual 
+	 *  signal drp[0..39]
+	 */
+	assert(brp != MIN_WORD);
+
+	for (k = 0; k <= 39; k++) {
+		drpp   = GSM_MULT_R( brp, drp[ k - Nr ] );
+		drp[k] = GSM_ADD( erp[k], drpp );
+	}
+
+	/*
+	 *  Update of the reconstructed short term residual signal
+	 *  drp[ -1..-120 ]
+	 */
+
+	for (k = 0; k <= 119; k++) drp[ -120 + k ] = drp[ -80 + k ];
+}
--- /dev/null
+++ b/libgsm/lpc.c
@@ -1,0 +1,338 @@
+/*
+ * Copyright 1992 by Jutta Degener and Carsten Bormann, Technische
+ * Universitaet Berlin.  See the accompanying file "COPYRIGHT" for
+ * details.  THERE IS ABSOLUTELY NO WARRANTY FOR THIS SOFTWARE.
+ */
+
+/* $Header: /cvsroot/sox/sox/libgsm/lpc.c,v 1.1 2007/09/06 16:50:55 cbagwell Exp $ */
+
+#include <stdio.h>
+#include <assert.h>
+
+#include "private.h"
+
+#include "gsm.h"
+
+/*
+ *  4.2.4 .. 4.2.7 LPC ANALYSIS SECTION
+ */
+
+/* 4.2.4 */
+
+
+static void Autocorrelation (
+	word     * s,		/* [0..159]	IN/OUT  */
+ 	longword * L_ACF)	/* [0..8]	OUT     */
+/*
+ *  The goal is to compute the array L_ACF[k].  The signal s[i] must
+ *  be scaled in order to avoid an overflow situation.
+ */
+{
+	register int	k, i;
+
+	word		temp, smax, scalauto;
+
+#ifdef	USE_FLOAT_MUL
+	float		float_s[160];
+#endif
+
+	/*  Dynamic scaling of the array  s[0..159]
+	 */
+
+	/*  Search for the maximum.
+	 */
+	smax = 0;
+	for (k = 0; k <= 159; k++) {
+		temp = GSM_ABS( s[k] );
+		if (temp > smax) smax = temp;
+	}
+
+	/*  Computation of the scaling factor.
+	 */
+	if (smax == 0) scalauto = 0;
+	else {
+		assert(smax > 0);
+		scalauto = 4 - gsm_norm( (longword)smax << 16 );/* sub(4,..) */
+	}
+
+	/*  Scaling of the array s[0...159]
+	 */
+
+	if (scalauto > 0) {
+
+# ifdef USE_FLOAT_MUL
+#   define SCALE(n)	\
+	case n: for (k = 0; k <= 159; k++) \
+			float_s[k] = (float)	\
+				(s[k] = GSM_MULT_R(s[k], 16384 >> (n-1)));\
+		break;
+# else 
+#   define SCALE(n)	\
+	case n: for (k = 0; k <= 159; k++) \
+			s[k] = GSM_MULT_R( s[k], 16384 >> (n-1) );\
+		break;
+# endif /* USE_FLOAT_MUL */
+
+		switch (scalauto) {
+		SCALE(1)
+		SCALE(2)
+		SCALE(3)
+		SCALE(4)
+		}
+# undef	SCALE
+	}
+# ifdef	USE_FLOAT_MUL
+	else for (k = 0; k <= 159; k++) float_s[k] = (float) s[k];
+# endif
+
+	/*  Compute the L_ACF[..].
+	 */
+	{
+# ifdef	USE_FLOAT_MUL
+		register float * sp = float_s;
+		register float   sl = *sp;
+
+#		define STEP(k)	 L_ACF[k] += (longword)(sl * sp[ -(k) ]);
+# else
+		word  * sp = s;
+		word    sl = *sp;
+
+#		define STEP(k)	 L_ACF[k] += ((longword)sl * sp[ -(k) ]);
+# endif
+
+#	define NEXTI	 sl = *++sp
+
+
+	for (k = 9; k--; L_ACF[k] = 0) ;
+
+	STEP (0);
+	NEXTI;
+	STEP(0); STEP(1);
+	NEXTI;
+	STEP(0); STEP(1); STEP(2);
+	NEXTI;
+	STEP(0); STEP(1); STEP(2); STEP(3);
+	NEXTI;
+	STEP(0); STEP(1); STEP(2); STEP(3); STEP(4);
+	NEXTI;
+	STEP(0); STEP(1); STEP(2); STEP(3); STEP(4); STEP(5);
+	NEXTI;
+	STEP(0); STEP(1); STEP(2); STEP(3); STEP(4); STEP(5); STEP(6);
+	NEXTI;
+	STEP(0); STEP(1); STEP(2); STEP(3); STEP(4); STEP(5); STEP(6); STEP(7);
+
+	for (i = 8; i <= 159; i++) {
+
+		NEXTI;
+
+		STEP(0);
+		STEP(1); STEP(2); STEP(3); STEP(4);
+		STEP(5); STEP(6); STEP(7); STEP(8);
+	}
+
+	for (k = 9; k--; L_ACF[k] <<= 1) ; 
+
+	}
+	/*   Rescaling of the array s[0..159]
+	 */
+	if (scalauto > 0) {
+		assert(scalauto <= 4); 
+		for (k = 160; k--; *s++ <<= scalauto) ;
+	}
+}
+
+#if defined(USE_FLOAT_MUL) && defined(FAST)
+
+static void Fast_Autocorrelation (
+	word * s,		/* [0..159]	IN/OUT  */
+ 	longword * L_ACF)	/* [0..8]	OUT     */
+{
+	register int	k, i;
+	float f_L_ACF[9];
+	float scale;
+
+	float          s_f[160];
+	register float *sf = s_f;
+
+	for (i = 0; i < 160; ++i) sf[i] = s[i];
+	for (k = 0; k <= 8; k++) {
+		register float L_temp2 = 0;
+		register float *sfl = sf - k;
+		for (i = k; i < 160; ++i) L_temp2 += sf[i] * sfl[i];
+		f_L_ACF[k] = L_temp2;
+	}
+	scale = MAX_LONGWORD / f_L_ACF[0];
+
+	for (k = 0; k <= 8; k++) {
+		L_ACF[k] = f_L_ACF[k] * scale;
+	}
+}
+#endif	/* defined (USE_FLOAT_MUL) && defined (FAST) */
+
+/* 4.2.5 */
+
+static void Reflection_coefficients (
+	longword	* L_ACF,		/* 0...8	IN	*/
+	register word	* r			/* 0...7	OUT 	*/
+)
+{
+	register int	i, m, n;
+	register word	temp;
+	register longword ltmp;
+	word		ACF[9];	/* 0..8 */
+	word		P[  9];	/* 0..8 */
+	word		K[  9]; /* 2..8 */
+
+	/*  Schur recursion with 16 bits arithmetic.
+	 */
+
+	if (L_ACF[0] == 0) {
+		for (i = 8; i--; *r++ = 0) ;
+		return;
+	}
+
+	assert( L_ACF[0] != 0 );
+	temp = gsm_norm( L_ACF[0] );
+
+	assert(temp >= 0 && temp < 32);
+
+	/* ? overflow ? */
+	for (i = 0; i <= 8; i++) ACF[i] = SASR( L_ACF[i] << temp, 16 );
+
+	/*   Initialize array P[..] and K[..] for the recursion.
+	 */
+
+	for (i = 1; i <= 7; i++) K[ i ] = ACF[ i ];
+	for (i = 0; i <= 8; i++) P[ i ] = ACF[ i ];
+
+	/*   Compute reflection coefficients
+	 */
+	for (n = 1; n <= 8; n++, r++) {
+
+		temp = P[1];
+		temp = GSM_ABS(temp);
+		if (P[0] < temp) {
+			for (i = n; i <= 8; i++) *r++ = 0;
+			return;
+		}
+
+		*r = gsm_div( temp, P[0] );
+
+		assert(*r >= 0);
+		if (P[1] > 0) *r = -*r;		/* r[n] = sub(0, r[n]) */
+		assert (*r != MIN_WORD);
+		if (n == 8) return; 
+
+		/*  Schur recursion
+		 */
+		temp = GSM_MULT_R( P[1], *r );
+		P[0] = GSM_ADD( P[0], temp );
+
+		for (m = 1; m <= 8 - n; m++) {
+			temp     = GSM_MULT_R( K[ m   ],    *r );
+			P[m]     = GSM_ADD(    P[ m+1 ],  temp );
+
+			temp     = GSM_MULT_R( P[ m+1 ],    *r );
+			K[m]     = GSM_ADD(    K[ m   ],  temp );
+		}
+	}
+}
+
+/* 4.2.6 */
+
+static void Transformation_to_Log_Area_Ratios (
+	register word	* r 			/* 0..7	   IN/OUT */
+)
+/*
+ *  The following scaling for r[..] and LAR[..] has been used:
+ *
+ *  r[..]   = integer( real_r[..]*32768. ); -1 <= real_r < 1.
+ *  LAR[..] = integer( real_LAR[..] * 16384 );
+ *  with -1.625 <= real_LAR <= 1.625
+ */
+{
+	register word	temp;
+	register int	i;
+
+
+	/* Computation of the LAR[0..7] from the r[0..7]
+	 */
+	for (i = 1; i <= 8; i++, r++) {
+
+		temp = *r;
+		temp = GSM_ABS(temp);
+		assert(temp >= 0);
+
+		if (temp < 22118) {
+			temp >>= 1;
+		} else if (temp < 31130) {
+			assert( temp >= 11059 );
+			temp -= 11059;
+		} else {
+			assert( temp >= 26112 );
+			temp -= 26112;
+			temp <<= 2;
+		}
+
+		*r = *r < 0 ? -temp : temp;
+		assert( *r != MIN_WORD );
+	}
+}
+
+/* 4.2.7 */
+
+static void Quantization_and_coding (
+	register word * LAR    	/* [0..7]	IN/OUT	*/
+)
+{
+	register word	temp;
+	longword	ltmp;
+
+
+	/*  This procedure needs four tables; the following equations
+	 *  give the optimum scaling for the constants:
+	 *  
+	 *  A[0..7] = integer( real_A[0..7] * 1024 )
+	 *  B[0..7] = integer( real_B[0..7] *  512 )
+	 *  MAC[0..7] = maximum of the LARc[0..7]
+	 *  MIC[0..7] = minimum of the LARc[0..7]
+	 */
+
+#	undef STEP
+#	define	STEP( A, B, MAC, MIC )		\
+		temp = GSM_MULT( A,   *LAR );	\
+		temp = GSM_ADD(  temp,   B );	\
+		temp = GSM_ADD(  temp, 256 );	\
+		temp = SASR(     temp,   9 );	\
+		*LAR  =  temp>MAC ? MAC - MIC : (temp<MIC ? 0 : temp - MIC); \
+		LAR++;
+
+	STEP(  20480,     0,  31, -32 );
+	STEP(  20480,     0,  31, -32 );
+	STEP(  20480,  2048,  15, -16 );
+	STEP(  20480, -2560,  15, -16 );
+
+	STEP(  13964,    94,   7,  -8 );
+	STEP(  15360, -1792,   7,  -8 );
+	STEP(   8534,  -341,   3,  -4 );
+	STEP(   9036, -1144,   3,  -4 );
+
+#	undef	STEP
+}
+
+void Gsm_LPC_Analysis (
+	struct gsm_state *S,
+	word 		 * s,		/* 0..159 signals	IN/OUT	*/
+        word 		 * LARc)	/* 0..7   LARc's	OUT	*/
+{
+	longword	L_ACF[9];
+
+#if defined(USE_FLOAT_MUL) && defined(FAST)
+	if (S->fast) Fast_Autocorrelation (s,	  L_ACF );
+	else
+#endif
+	Autocorrelation			  (s,	  L_ACF	);
+	Reflection_coefficients		  (L_ACF, LARc	);
+	Transformation_to_Log_Area_Ratios (LARc);
+	Quantization_and_coding		  (LARc);
+}
--- /dev/null
+++ b/libgsm/preprocess.c
@@ -1,0 +1,112 @@
+/*
+ * Copyright 1992 by Jutta Degener and Carsten Bormann, Technische
+ * Universitaet Berlin.  See the accompanying file "COPYRIGHT" for
+ * details.  THERE IS ABSOLUTELY NO WARRANTY FOR THIS SOFTWARE.
+ */
+
+/* $Header: /cvsroot/sox/sox/libgsm/preprocess.c,v 1.1 2007/09/06 16:50:55 cbagwell Exp $ */
+
+#include	<stdio.h>
+#include	<assert.h>
+
+#include "private.h"
+
+#include	"gsm.h"
+
+/*	4.2.0 .. 4.2.3	PREPROCESSING SECTION
+ *  
+ *  	After A-law to linear conversion (or directly from the
+ *   	Ato D converter) the following scaling is assumed for
+ * 	input to the RPE-LTP algorithm:
+ *
+ *      in:  0.1.....................12
+ *	     S.v.v.v.v.v.v.v.v.v.v.v.v.*.*.*
+ *
+ *	Where S is the sign bit, v a valid bit, and * a "don't care" bit.
+ * 	The original signal is called sop[..]
+ *
+ *      out:   0.1................... 12 
+ *	     S.S.v.v.v.v.v.v.v.v.v.v.v.v.0.0
+ */
+
+
+void Gsm_Preprocess (
+	struct gsm_state * S,
+	word		 * s,
+	word 		 * so )		/* [0..159] 	IN/OUT	*/
+{
+
+	word       z1 = S->z1;
+	longword L_z2 = S->L_z2;
+	word 	   mp = S->mp;
+
+	word 	   	s1;
+	longword      L_s2;
+
+	longword      L_temp;
+
+	word		msp, lsp;
+	word		SO;
+
+	longword	ltmp;		/* for   ADD */
+	ulongword	utmp;		/* for L_ADD */
+
+	register int		k = 160;
+
+	while (k--) {
+
+	/*  4.2.1   Downscaling of the input signal
+	 */
+		SO = SASR( *s, 3 ) << 2;
+		s++;
+
+		assert (SO >= -0x4000);	/* downscaled by     */
+		assert (SO <=  0x3FFC);	/* previous routine. */
+
+
+	/*  4.2.2   Offset compensation
+	 * 
+	 *  This part implements a high-pass filter and requires extended
+	 *  arithmetic precision for the recursive part of this filter.
+	 *  The input of this procedure is the array so[0...159] and the
+	 *  output the array sof[ 0...159 ].
+	 */
+		/*   Compute the non-recursive part
+		 */
+
+		s1 = SO - z1;			/* s1 = gsm_sub( *so, z1 ); */
+		z1 = SO;
+
+		assert(s1 != MIN_WORD);
+
+		/*   Compute the recursive part
+		 */
+		L_s2 = s1;
+		L_s2 <<= 15;
+
+		/*   Execution of a 31 bv 16 bits multiplication
+		 */
+
+		msp = SASR( L_z2, 15 );
+		lsp = L_z2-((longword)msp<<15); /* gsm_L_sub(L_z2,(msp<<15)); */
+
+		L_s2  += GSM_MULT_R( lsp, 32735 );
+		L_temp = (longword)msp * 32735; /* GSM_L_MULT(msp,32735) >> 1;*/
+		L_z2   = GSM_L_ADD( L_temp, L_s2 );
+
+		/*    Compute sof[k] with rounding
+		 */
+		L_temp = GSM_L_ADD( L_z2, 16384 );
+
+	/*   4.2.3  Preemphasis
+	 */
+
+		msp   = GSM_MULT_R( mp, -28180 );
+		mp    = SASR( L_temp, 15 );
+		*so++ = GSM_ADD( mp, msp );
+	}
+
+	S->z1   = z1;
+	S->L_z2 = L_z2;
+	S->mp   = mp;
+}
--- /dev/null
+++ b/libgsm/private.h
@@ -1,0 +1,264 @@
+/*
+ * Copyright 1992 by Jutta Degener and Carsten Bormann, Technische
+ * Universitaet Berlin.  See the accompanying file "COPYRIGHT" for
+ * details.  THERE IS ABSOLUTELY NO WARRANTY FOR THIS SOFTWARE.
+ */
+
+/*$Header: /cvsroot/sox/sox/libgsm/private.h,v 1.1 2007/09/06 16:50:56 cbagwell Exp $*/
+
+#ifndef	PRIVATE_H
+#define	PRIVATE_H
+
+typedef short			word;		/* 16 bit signed int	*/
+typedef long			longword;	/* 32 bit signed int	*/
+
+typedef unsigned short		uword;		/* unsigned word	*/
+typedef unsigned long		ulongword;	/* unsigned longword	*/
+
+struct gsm_state {
+
+	word		dp0[ 280 ];
+
+	word		z1;		/* preprocessing.c, Offset_com. */
+	longword	L_z2;		/*                  Offset_com. */
+	int		mp;		/*                  Preemphasis	*/
+
+	word		u[8];		/* short_term_aly_filter.c	*/
+	word		LARpp[2][8]; 	/*                              */
+	word		j;		/*                              */
+
+	word            ltp_cut;        /* long_term.c, LTP crosscorr.  */
+	word		nrp; /* 40 */	/* long_term.c, synthesis	*/
+	word		v[9];		/* short_term.c, synthesis	*/
+	word		msr;		/* decoder.c,	Postprocessing	*/
+
+	char		verbose;	/* only used if !NDEBUG		*/
+	char		fast;		/* only used if FAST		*/
+
+	char		wav_fmt;	/* only used if WAV49 defined	*/
+	unsigned char	frame_index;	/*            odd/even chaining	*/
+	unsigned char	frame_chain;	/*   half-byte to carry forward	*/
+};
+
+
+#define	MIN_WORD	(-32767 - 1)
+#define	MAX_WORD	  32767
+
+#define	MIN_LONGWORD	(-2147483647 - 1)
+#define	MAX_LONGWORD	  2147483647
+
+#ifdef	SASR		/* flag: >> is a signed arithmetic shift right */
+#undef	SASR
+#define	SASR(x, by)	((x) >> (by))
+#else
+#define	SASR(x, by)	((x) >= 0 ? (x) >> (by) : (~(-((x) + 1) >> (by))))
+#endif	/* SASR */
+
+/*
+ *	Prototypes from add.c
+ */
+extern word	gsm_mult 	(word a, word b);
+extern longword gsm_L_mult 	(word a, word b);
+extern word	gsm_mult_r	(word a, word b);
+
+extern word	gsm_div  	(word num, word denum);
+
+extern word	gsm_add 	( word a, word b );
+extern longword gsm_L_add 	( longword a, longword b );
+
+extern word	gsm_sub 	(word a, word b);
+extern longword gsm_L_sub 	(longword a, longword b);
+
+extern word	gsm_abs 	(word a);
+
+extern word	gsm_norm 	( longword a );
+
+extern longword gsm_L_asl  	(longword a, int n);
+extern word	gsm_asl 	(word a, int n);
+
+extern longword gsm_L_asr  	(longword a, int n);
+extern word	gsm_asr  	(word a, int n);
+
+/*
+ *  Inlined functions from add.h 
+ */
+
+/* 
+ * #define GSM_MULT_R(a, b) (* word a, word b, !(a == b == MIN_WORD) *)	\
+ *	(0x0FFFF & SASR(((longword)(a) * (longword)(b) + 16384), 15))
+ */
+#define GSM_MULT_R(a, b) /* word a, word b, !(a == b == MIN_WORD) */	\
+	(SASR( ((longword)(a) * (longword)(b) + 16384), 15 ))
+
+# define GSM_MULT(a,b)	 /* word a, word b, !(a == b == MIN_WORD) */	\
+	(SASR( ((longword)(a) * (longword)(b)), 15 ))
+
+# define GSM_L_MULT(a, b) /* word a, word b */	\
+	(((longword)(a) * (longword)(b)) << 1)
+
+# define GSM_L_ADD(a, b)	\
+	( (a) <  0 ? ( (b) >= 0 ? (a) + (b)	\
+		 : (utmp = (ulongword)-((a) + 1) + (ulongword)-((b) + 1)) \
+		   >= MAX_LONGWORD ? MIN_LONGWORD : -(longword)utmp-2 )   \
+	: ((b) <= 0 ? (a) + (b)   \
+	          : (utmp = (ulongword)(a) + (ulongword)(b)) >= MAX_LONGWORD \
+		    ? MAX_LONGWORD : utmp))
+
+/*
+ * # define GSM_ADD(a, b)	\
+ * 	((ltmp = (longword)(a) + (longword)(b)) >= MAX_WORD \
+ * 	? MAX_WORD : ltmp <= MIN_WORD ? MIN_WORD : ltmp)
+ */
+/* Nonportable, but faster: */
+
+#define	GSM_ADD(a, b)	\
+	((ulongword)((ltmp = (longword)(a) + (longword)(b)) - MIN_WORD) > \
+		MAX_WORD - MIN_WORD ? (ltmp > 0 ? MAX_WORD : MIN_WORD) : ltmp)
+
+# define GSM_SUB(a, b)	\
+	((ltmp = (longword)(a) - (longword)(b)) >= MAX_WORD \
+	? MAX_WORD : ltmp <= MIN_WORD ? MIN_WORD : ltmp)
+
+# define GSM_ABS(a)	((a) < 0 ? ((a) == MIN_WORD ? MAX_WORD : -(a)) : (a))
+
+/* Use these if necessary:
+
+# define GSM_MULT_R(a, b)	gsm_mult_r(a, b)
+# define GSM_MULT(a, b)		gsm_mult(a, b)
+# define GSM_L_MULT(a, b)	gsm_L_mult(a, b)
+
+# define GSM_L_ADD(a, b)	gsm_L_add(a, b)
+# define GSM_ADD(a, b)		gsm_add(a, b)
+# define GSM_SUB(a, b)		gsm_sub(a, b)
+
+# define GSM_ABS(a)		gsm_abs(a)
+
+*/
+
+/*
+ *  More prototypes from implementations..
+ */
+extern void Gsm_Coder (
+		struct gsm_state	* S,
+		word	* s,	/* [0..159] samples		IN	*/
+		word	* LARc,	/* [0..7] LAR coefficients	OUT	*/
+		word	* Nc,	/* [0..3] LTP lag		OUT 	*/
+		word	* bc,	/* [0..3] coded LTP gain	OUT 	*/
+		word	* Mc,	/* [0..3] RPE grid selection	OUT     */
+		word	* xmaxc,/* [0..3] Coded maximum amplitude OUT	*/
+		word	* xMc	/* [13*4] normalized RPE samples OUT	*/);
+
+extern void Gsm_Long_Term_Predictor (		/* 4x for 160 samples */
+		struct gsm_state * S,
+		word	* d,	/* [0..39]   residual signal	IN	*/
+		word	* dp,	/* [-120..-1] d'		IN	*/
+		word	* e,	/* [0..40] 			OUT	*/
+		word	* dpp,	/* [0..40] 			OUT	*/
+		word	* Nc,	/* correlation lag		OUT	*/
+		word	* bc	/* gain factor			OUT	*/);
+
+extern void Gsm_LPC_Analysis (
+		struct gsm_state * S,
+		word * s,	 /* 0..159 signals	IN/OUT	*/
+	        word * LARc);   /* 0..7   LARc's	OUT	*/
+
+extern void Gsm_Preprocess (
+		struct gsm_state * S,
+		word * s, word * so);
+
+extern void Gsm_Encoding (
+		struct gsm_state * S,
+		word	* e,	
+		word	* ep,	
+		word	* xmaxc,
+		word	* Mc,	
+		word	* xMc);
+
+extern void Gsm_Short_Term_Analysis_Filter (
+		struct gsm_state * S,
+		word	* LARc,	/* coded log area ratio [0..7]  IN	*/
+		word	* d	/* st res. signal [0..159]	IN/OUT	*/);
+
+extern void Gsm_Decoder (
+		struct gsm_state * S,
+		word	* LARcr,	/* [0..7]		IN	*/
+		word	* Ncr,		/* [0..3] 		IN 	*/
+		word	* bcr,		/* [0..3]		IN	*/
+		word	* Mcr,		/* [0..3] 		IN 	*/
+		word	* xmaxcr,	/* [0..3]		IN 	*/
+		word	* xMcr,		/* [0..13*4]		IN	*/
+		word	* s);		/* [0..159]		OUT 	*/
+
+extern void Gsm_Decoding (
+		struct gsm_state * S,
+		word 	xmaxcr,
+		word	Mcr,
+		word	* xMcr,  	/* [0..12]		IN	*/
+		word	* erp); 	/* [0..39]		OUT 	*/
+
+extern void Gsm_Long_Term_Synthesis_Filtering (
+		struct gsm_state* S,
+		word	Ncr,
+		word	bcr,
+		word	* erp,		/* [0..39]		  IN 	*/
+		word	* drp); 	/* [-120..-1] IN, [0..40] OUT 	*/
+
+void Gsm_RPE_Decoding (
+	struct gsm_state *S,
+		word xmaxcr,
+		word Mcr,
+		word * xMcr,  /* [0..12], 3 bits             IN      */
+		word * erp); /* [0..39]                     OUT     */
+
+void Gsm_RPE_Encoding (
+		struct gsm_state * S,
+		word    * e,            /* -5..-1][0..39][40..44     IN/OUT  */
+		word    * xmaxc,        /*                              OUT */
+		word    * Mc,           /*                              OUT */
+		word    * xMc);        /* [0..12]                      OUT */
+
+extern void Gsm_Short_Term_Synthesis_Filter (
+		struct gsm_state * S,
+		word	* LARcr, 	/* log area ratios [0..7]  IN	*/
+		word	* drp,		/* received d [0...39]	   IN	*/
+		word	* s);		/* signal   s [0..159]	  OUT	*/
+
+extern void Gsm_Update_of_reconstructed_short_time_residual_signal (
+		word	* dpp,		/* [0...39]	IN	*/
+		word	* ep,		/* [0...39]	IN	*/
+		word	* dp);		/* [-120...-1]  IN/OUT 	*/
+
+/*
+ *  Tables from table.c
+ */
+#ifndef	GSM_TABLE_C
+
+extern word gsm_A[8], gsm_B[8], gsm_MIC[8], gsm_MAC[8];
+extern word gsm_INVA[8];
+extern word gsm_DLB[4], gsm_QLB[4];
+extern word gsm_H[11];
+extern word gsm_NRFAC[8];
+extern word gsm_FAC[8];
+
+#endif	/* GSM_TABLE_C */
+
+/*
+ *  Debugging
+ */
+#ifdef NDEBUG
+
+#	define	gsm_debug_words(a, b, c, d)		/* nil */
+#	define	gsm_debug_longwords(a, b, c, d)		/* nil */
+#	define	gsm_debug_word(a, b)			/* nil */
+#	define	gsm_debug_longword(a, b)		/* nil */
+
+#else	/* !NDEBUG => DEBUG */
+
+	extern void  gsm_debug_words     (char * name, int, int, word *);
+	extern void  gsm_debug_longwords (char * name, int, int, longword *);
+	extern void  gsm_debug_longword  (char * name, longword);
+	extern void  gsm_debug_word      (char * name, word);
+
+#endif /* !NDEBUG */
+
+#endif	/* PRIVATE_H */
--- /dev/null
+++ b/libgsm/rpe.c
@@ -1,0 +1,487 @@
+/*
+ * Copyright 1992 by Jutta Degener and Carsten Bormann, Technische
+ * Universitaet Berlin.  See the accompanying file "COPYRIGHT" for
+ * details.  THERE IS ABSOLUTELY NO WARRANTY FOR THIS SOFTWARE.
+ */
+
+/* $Header: /cvsroot/sox/sox/libgsm/rpe.c,v 1.1 2007/09/06 16:50:56 cbagwell Exp $ */
+
+#include <stdio.h>
+#include <assert.h>
+
+#include "private.h"
+
+#include "gsm.h"
+
+/*  4.2.13 .. 4.2.17  RPE ENCODING SECTION
+ */
+
+/* 4.2.13 */
+
+static void Weighting_filter (
+	register word	* e,		/* signal [-5..0.39.44]	IN  */
+	word		* x		/* signal [0..39]	OUT */
+)
+/*
+ *  The coefficients of the weighting filter are stored in a table
+ *  (see table 4.4).  The following scaling is used:
+ *
+ *	H[0..10] = integer( real_H[ 0..10] * 8192 ); 
+ */
+{
+	/* word			wt[ 50 ]; */
+
+	register longword	L_result;
+	register int		k /* , i */ ;
+
+	/*  Initialization of a temporary working array wt[0...49]
+	 */
+
+	/* for (k =  0; k <=  4; k++) wt[k] = 0;
+	 * for (k =  5; k <= 44; k++) wt[k] = *e++;
+	 * for (k = 45; k <= 49; k++) wt[k] = 0;
+	 *
+	 *  (e[-5..-1] and e[40..44] are allocated by the caller,
+	 *  are initially zero and are not written anywhere.)
+	 */
+	e -= 5;
+
+	/*  Compute the signal x[0..39]
+	 */ 
+	for (k = 0; k <= 39; k++) {
+
+		L_result = 8192 >> 1;
+
+		/* for (i = 0; i <= 10; i++) {
+		 *	L_temp   = GSM_L_MULT( wt[k+i], gsm_H[i] );
+		 *	L_result = GSM_L_ADD( L_result, L_temp );
+		 * }
+		 */
+
+#undef	STEP
+#define	STEP( i, H )	(e[ k + i ] * (longword)H)
+
+		/*  Every one of these multiplications is done twice --
+		 *  but I don't see an elegant way to optimize this. 
+		 *  Do you?
+		 */
+
+#ifdef	STUPID_COMPILER
+		L_result += STEP(	0, 	-134 ) ;
+		L_result += STEP(	1, 	-374 )  ;
+	               /* + STEP(	2, 	0    )  */
+		L_result += STEP(	3, 	2054 ) ;
+		L_result += STEP(	4, 	5741 ) ;
+		L_result += STEP(	5, 	8192 ) ;
+		L_result += STEP(	6, 	5741 ) ;
+		L_result += STEP(	7, 	2054 ) ;
+	 	       /* + STEP(	8, 	0    )  */
+		L_result += STEP(	9, 	-374 ) ;
+		L_result += STEP(	10, 	-134 ) ;
+#else
+		L_result +=
+		  STEP(	0, 	-134 ) 
+		+ STEP(	1, 	-374 ) 
+	     /* + STEP(	2, 	0    )  */
+		+ STEP(	3, 	2054 ) 
+		+ STEP(	4, 	5741 ) 
+		+ STEP(	5, 	8192 ) 
+		+ STEP(	6, 	5741 ) 
+		+ STEP(	7, 	2054 ) 
+	     /* + STEP(	8, 	0    )  */
+		+ STEP(	9, 	-374 ) 
+		+ STEP(10, 	-134 )
+		;
+#endif
+
+		/* L_result = GSM_L_ADD( L_result, L_result ); (* scaling(x2) *)
+		 * L_result = GSM_L_ADD( L_result, L_result ); (* scaling(x4) *)
+		 *
+		 * x[k] = SASR( L_result, 16 );
+		 */
+
+		/* 2 adds vs. >>16 => 14, minus one shift to compensate for
+		 * those we lost when replacing L_MULT by '*'.
+		 */
+
+		L_result = SASR( L_result, 13 );
+		x[k] =  (  L_result < MIN_WORD ? MIN_WORD
+			: (L_result > MAX_WORD ? MAX_WORD : L_result ));
+	}
+}
+
+/* 4.2.14 */
+
+static void RPE_grid_selection (
+	word		* x,		/* [0..39]		IN  */ 
+	word		* xM,		/* [0..12]		OUT */
+	word		* Mc_out	/*			OUT */
+)
+/*
+ *  The signal x[0..39] is used to select the RPE grid which is
+ *  represented by Mc.
+ */
+{
+	/* register word	temp1;	*/
+	register int		/* m, */  i;
+	register longword	L_result, L_temp;
+	longword		EM;	/* xxx should be L_EM? */
+	word			Mc;
+
+	longword		L_common_0_3;
+
+	EM = 0;
+	Mc = 0;
+
+	/* for (m = 0; m <= 3; m++) {
+	 *	L_result = 0;
+	 *
+	 *
+	 *	for (i = 0; i <= 12; i++) {
+	 *
+	 *		temp1    = SASR( x[m + 3*i], 2 );
+	 *
+	 *		assert(temp1 != MIN_WORD);
+	 *
+	 *		L_temp   = GSM_L_MULT( temp1, temp1 );
+	 *		L_result = GSM_L_ADD( L_temp, L_result );
+	 *	}
+	 * 
+	 *	if (L_result > EM) {
+	 *		Mc = m;
+	 *		EM = L_result;
+	 *	}
+	 * }
+	 */
+
+#undef	STEP
+#define	STEP( m, i )		L_temp = SASR( x[m + 3 * i], 2 );	\
+				L_result += L_temp * L_temp;
+
+	/* common part of 0 and 3 */
+
+	L_result = 0;
+	STEP( 0, 1 ); STEP( 0, 2 ); STEP( 0, 3 ); STEP( 0, 4 );
+	STEP( 0, 5 ); STEP( 0, 6 ); STEP( 0, 7 ); STEP( 0, 8 );
+	STEP( 0, 9 ); STEP( 0, 10); STEP( 0, 11); STEP( 0, 12);
+	L_common_0_3 = L_result;
+
+	/* i = 0 */
+
+	STEP( 0, 0 );
+	L_result <<= 1;	/* implicit in L_MULT */
+	EM = L_result;
+
+	/* i = 1 */
+
+	L_result = 0;
+	STEP( 1, 0 );
+	STEP( 1, 1 ); STEP( 1, 2 ); STEP( 1, 3 ); STEP( 1, 4 );
+	STEP( 1, 5 ); STEP( 1, 6 ); STEP( 1, 7 ); STEP( 1, 8 );
+	STEP( 1, 9 ); STEP( 1, 10); STEP( 1, 11); STEP( 1, 12);
+	L_result <<= 1;
+	if (L_result > EM) {
+		Mc = 1;
+	 	EM = L_result;
+	}
+
+	/* i = 2 */
+
+	L_result = 0;
+	STEP( 2, 0 );
+	STEP( 2, 1 ); STEP( 2, 2 ); STEP( 2, 3 ); STEP( 2, 4 );
+	STEP( 2, 5 ); STEP( 2, 6 ); STEP( 2, 7 ); STEP( 2, 8 );
+	STEP( 2, 9 ); STEP( 2, 10); STEP( 2, 11); STEP( 2, 12);
+	L_result <<= 1;
+	if (L_result > EM) {
+		Mc = 2;
+	 	EM = L_result;
+	}
+
+	/* i = 3 */
+
+	L_result = L_common_0_3;
+	STEP( 3, 12 );
+	L_result <<= 1;
+	if (L_result > EM) {
+		Mc = 3;
+	 	EM = L_result;
+	}
+
+	/**/
+
+	/*  Down-sampling by a factor 3 to get the selected xM[0..12]
+	 *  RPE sequence.
+	 */
+	for (i = 0; i <= 12; i ++) xM[i] = x[Mc + 3*i];
+	*Mc_out = Mc;
+}
+
+/* 4.12.15 */
+
+static void APCM_quantization_xmaxc_to_exp_mant (
+	word		xmaxc,		/* IN 	*/
+	word		* exp_out,	/* OUT	*/
+	word		* mant_out )	/* OUT  */
+{
+	word	exp, mant;
+
+	/* Compute exponent and mantissa of the decoded version of xmaxc
+	 */
+
+	exp = 0;
+	if (xmaxc > 15) exp = SASR(xmaxc, 3) - 1;
+	mant = xmaxc - (exp << 3);
+
+	if (mant == 0) {
+		exp  = -4;
+		mant = 7;
+	}
+	else {
+		while (mant <= 7) {
+			mant = mant << 1 | 1;
+			exp--;
+		}
+		mant -= 8;
+	}
+
+	assert( exp  >= -4 && exp <= 6 );
+	assert( mant >= 0 && mant <= 7 );
+
+	*exp_out  = exp;
+	*mant_out = mant;
+}
+
+static void APCM_quantization (
+	word		* xM,		/* [0..12]		IN	*/
+
+	word		* xMc,		/* [0..12]		OUT	*/
+	word		* mant_out,	/* 			OUT	*/
+	word		* exp_out,	/*			OUT	*/
+	word		* xmaxc_out	/*			OUT	*/
+)
+{
+	int	i, itest;
+
+	word	xmax, xmaxc, temp, temp1, temp2;
+	word	exp, mant;
+
+
+	/*  Find the maximum absolute value xmax of xM[0..12].
+	 */
+
+	xmax = 0;
+	for (i = 0; i <= 12; i++) {
+		temp = xM[i];
+		temp = GSM_ABS(temp);
+		if (temp > xmax) xmax = temp;
+	}
+
+	/*  Qantizing and coding of xmax to get xmaxc.
+	 */
+
+	exp   = 0;
+	temp  = SASR( xmax, 9 );
+	itest = 0;
+
+	for (i = 0; i <= 5; i++) {
+
+		itest |= (temp <= 0);
+		temp = SASR( temp, 1 );
+
+		assert(exp <= 5);
+		if (itest == 0) exp++;		/* exp = add (exp, 1) */
+	}
+
+	assert(exp <= 6 && exp >= 0);
+	temp = exp + 5;
+
+	assert(temp <= 11 && temp >= 0);
+	xmaxc = gsm_add( SASR(xmax, temp), exp << 3 );
+
+	/*   Quantizing and coding of the xM[0..12] RPE sequence
+	 *   to get the xMc[0..12]
+	 */
+
+	APCM_quantization_xmaxc_to_exp_mant( xmaxc, &exp, &mant );
+
+	/*  This computation uses the fact that the decoded version of xmaxc
+	 *  can be calculated by using the exponent and the mantissa part of
+	 *  xmaxc (logarithmic table).
+	 *  So, this method avoids any division and uses only a scaling
+	 *  of the RPE samples by a function of the exponent.  A direct 
+	 *  multiplication by the inverse of the mantissa (NRFAC[0..7]
+	 *  found in table 4.5) gives the 3 bit coded version xMc[0..12]
+	 *  of the RPE samples.
+	 */
+
+
+	/* Direct computation of xMc[0..12] using table 4.5
+	 */
+
+	assert( exp <= 4096 && exp >= -4096);
+	assert( mant >= 0 && mant <= 7 ); 
+
+	temp1 = 6 - exp;		/* normalization by the exponent */
+	temp2 = gsm_NRFAC[ mant ];  	/* inverse mantissa 		 */
+
+	for (i = 0; i <= 12; i++) {
+
+		assert(temp1 >= 0 && temp1 < 16);
+
+		temp = xM[i] << temp1;
+		temp = GSM_MULT( temp, temp2 );
+		temp = SASR(temp, 12);
+		xMc[i] = temp + 4;		/* see note below */
+	}
+
+	/*  NOTE: This equation is used to make all the xMc[i] positive.
+	 */
+
+	*mant_out  = mant;
+	*exp_out   = exp;
+	*xmaxc_out = xmaxc;
+}
+
+/* 4.2.16 */
+
+static void APCM_inverse_quantization (
+	register word	* xMc,	/* [0..12]			IN 	*/
+	word		mant,
+	word		exp,
+	register word	* xMp)	/* [0..12]			OUT 	*/
+/* 
+ *  This part is for decoding the RPE sequence of coded xMc[0..12]
+ *  samples to obtain the xMp[0..12] array.  Table 4.6 is used to get
+ *  the mantissa of xmaxc (FAC[0..7]).
+ */
+{
+	int	i;
+	word	temp, temp1, temp2, temp3;
+	longword	ltmp;
+
+	assert( mant >= 0 && mant <= 7 ); 
+
+	temp1 = gsm_FAC[ mant ];	/* see 4.2-15 for mant */
+	temp2 = gsm_sub( 6, exp );	/* see 4.2-15 for exp  */
+	temp3 = gsm_asl( 1, gsm_sub( temp2, 1 ));
+
+	for (i = 13; i--;) {
+
+		assert( *xMc <= 7 && *xMc >= 0 ); 	/* 3 bit unsigned */
+
+		/* temp = gsm_sub( *xMc++ << 1, 7 ); */
+		temp = (*xMc++ << 1) - 7;	        /* restore sign   */
+		assert( temp <= 7 && temp >= -7 ); 	/* 4 bit signed   */
+
+		temp <<= 12;				/* 16 bit signed  */
+		temp = GSM_MULT_R( temp1, temp );
+		temp = GSM_ADD( temp, temp3 );
+		*xMp++ = gsm_asr( temp, temp2 );
+	}
+}
+
+/* 4.2.17 */
+
+static void RPE_grid_positioning (
+	word		Mc,		/* grid position	IN	*/
+	register word	* xMp,		/* [0..12]		IN	*/
+	register word	* ep		/* [0..39]		OUT	*/
+)
+/*
+ *  This procedure computes the reconstructed long term residual signal
+ *  ep[0..39] for the LTP analysis filter.  The inputs are the Mc
+ *  which is the grid position selection and the xMp[0..12] decoded
+ *  RPE samples which are upsampled by a factor of 3 by inserting zero
+ *  values.
+ */
+{
+	int	i = 13;
+
+	assert(0 <= Mc && Mc <= 3);
+
+        switch (Mc) {
+                case 3: *ep++ = 0;
+                case 2:  do {
+                                *ep++ = 0;
+                case 1:         *ep++ = 0;
+                case 0:         *ep++ = *xMp++;
+                         } while (--i);
+        }
+        while (++Mc < 4) *ep++ = 0;
+
+	/*
+
+	int i, k;
+	for (k = 0; k <= 39; k++) ep[k] = 0;
+	for (i = 0; i <= 12; i++) {
+		ep[ Mc + (3*i) ] = xMp[i];
+	}
+	*/
+}
+
+/* 4.2.18 */
+
+/*  This procedure adds the reconstructed long term residual signal
+ *  ep[0..39] to the estimated signal dpp[0..39] from the long term
+ *  analysis filter to compute the reconstructed short term residual
+ *  signal dp[-40..-1]; also the reconstructed short term residual
+ *  array dp[-120..-41] is updated.
+ */
+
+#if 0	/* Has been inlined in code.c */
+void Gsm_Update_of_reconstructed_short_time_residual_signal P3((dpp, ep, dp),
+	word	* dpp,		/* [0...39]	IN	*/
+	word	* ep,		/* [0...39]	IN	*/
+	word	* dp)		/* [-120...-1]  IN/OUT 	*/
+{
+	int 		k;
+
+	for (k = 0; k <= 79; k++) 
+		dp[ -120 + k ] = dp[ -80 + k ];
+
+	for (k = 0; k <= 39; k++)
+		dp[ -40 + k ] = gsm_add( ep[k], dpp[k] );
+}
+#endif	/* Has been inlined in code.c */
+
+void Gsm_RPE_Encoding (
+
+	struct gsm_state * S,
+
+	word	* e,		/* -5..-1][0..39][40..44	IN/OUT  */
+	word	* xmaxc,	/* 				OUT */
+	word	* Mc,		/* 			  	OUT */
+	word	* xMc)		/* [0..12]			OUT */
+{
+	word	x[40];
+	word	xM[13], xMp[13];
+	word	mant, exp;
+
+	Weighting_filter(e, x);
+	RPE_grid_selection(x, xM, Mc);
+
+	APCM_quantization(	xM, xMc, &mant, &exp, xmaxc);
+	APCM_inverse_quantization(  xMc,  mant,  exp, xMp);
+
+	RPE_grid_positioning( *Mc, xMp, e );
+
+}
+
+void Gsm_RPE_Decoding (
+	struct gsm_state	* S,
+
+	word 		xmaxcr,
+	word		Mcr,
+	word		* xMcr,  /* [0..12], 3 bits 		IN	*/
+	word		* erp	 /* [0..39]			OUT 	*/
+)
+{
+	word	exp, mant;
+	word	xMp[ 13 ];
+
+	APCM_quantization_xmaxc_to_exp_mant( xmaxcr, &exp, &mant );
+	APCM_inverse_quantization( xMcr, mant, exp, xMp );
+	RPE_grid_positioning( Mcr, xMp, erp );
+
+}
--- /dev/null
+++ b/libgsm/short_term.c
@@ -1,0 +1,428 @@
+/*
+ * Copyright 1992 by Jutta Degener and Carsten Bormann, Technische
+ * Universitaet Berlin.  See the accompanying file "COPYRIGHT" for
+ * details.  THERE IS ABSOLUTELY NO WARRANTY FOR THIS SOFTWARE.
+ */
+
+/* $Header: /cvsroot/sox/sox/libgsm/short_term.c,v 1.1 2007/09/06 16:50:56 cbagwell Exp $ */
+
+#include <stdio.h>
+#include <assert.h>
+
+#include "private.h"
+
+#include "gsm.h"
+
+/*
+ *  SHORT TERM ANALYSIS FILTERING SECTION
+ */
+
+/* 4.2.8 */
+
+static void Decoding_of_the_coded_Log_Area_Ratios (
+	word 	* LARc,		/* coded log area ratio	[0..7] 	IN	*/
+	word	* LARpp)	/* out: decoded ..			*/
+{
+	register word	temp1 /* , temp2 */;
+	register long	ltmp;	/* for GSM_ADD */
+
+	/*  This procedure requires for efficient implementation
+	 *  two tables.
+ 	 *
+	 *  INVA[1..8] = integer( (32768 * 8) / real_A[1..8])
+	 *  MIC[1..8]  = minimum value of the LARc[1..8]
+	 */
+
+	/*  Compute the LARpp[1..8]
+	 */
+
+	/* 	for (i = 1; i <= 8; i++, B++, MIC++, INVA++, LARc++, LARpp++) {
+	 *
+	 *		temp1  = GSM_ADD( *LARc, *MIC ) << 10;
+	 *		temp2  = *B << 1;
+	 *		temp1  = GSM_SUB( temp1, temp2 );
+	 *
+	 *		assert(*INVA != MIN_WORD);
+	 *
+	 *		temp1  = GSM_MULT_R( *INVA, temp1 );
+	 *		*LARpp = GSM_ADD( temp1, temp1 );
+	 *	}
+	 */
+
+#undef	STEP
+#define	STEP( B, MIC, INVA )	\
+		temp1    = GSM_ADD( *LARc++, MIC ) << 10;	\
+		temp1    = GSM_SUB( temp1, B << 1 );		\
+		temp1    = GSM_MULT_R( INVA, temp1 );		\
+		*LARpp++ = GSM_ADD( temp1, temp1 );
+
+	STEP(      0,  -32,  13107 );
+	STEP(      0,  -32,  13107 );
+	STEP(   2048,  -16,  13107 );
+	STEP(  -2560,  -16,  13107 );
+
+	STEP(     94,   -8,  19223 );
+	STEP(  -1792,   -8,  17476 );
+	STEP(   -341,   -4,  31454 );
+	STEP(  -1144,   -4,  29708 );
+
+	/* NOTE: the addition of *MIC is used to restore
+	 * 	 the sign of *LARc.
+	 */
+}
+
+/* 4.2.9 */
+/* Computation of the quantized reflection coefficients 
+ */
+
+/* 4.2.9.1  Interpolation of the LARpp[1..8] to get the LARp[1..8]
+ */
+
+/*
+ *  Within each frame of 160 analyzed speech samples the short term
+ *  analysis and synthesis filters operate with four different sets of
+ *  coefficients, derived from the previous set of decoded LARs(LARpp(j-1))
+ *  and the actual set of decoded LARs (LARpp(j))
+ *
+ * (Initial value: LARpp(j-1)[1..8] = 0.)
+ */
+
+static void Coefficients_0_12 (
+	register word * LARpp_j_1,
+	register word * LARpp_j,
+	register word * LARp)
+{
+	register int 	i;
+	register longword ltmp;
+
+	for (i = 1; i <= 8; i++, LARp++, LARpp_j_1++, LARpp_j++) {
+		*LARp = GSM_ADD( SASR( *LARpp_j_1, 2 ), SASR( *LARpp_j, 2 ));
+		*LARp = GSM_ADD( *LARp,  SASR( *LARpp_j_1, 1));
+	}
+}
+
+static void Coefficients_13_26 (
+	register word * LARpp_j_1,
+	register word * LARpp_j,
+	register word * LARp)
+{
+	register int i;
+	register longword ltmp;
+	for (i = 1; i <= 8; i++, LARpp_j_1++, LARpp_j++, LARp++) {
+		*LARp = GSM_ADD( SASR( *LARpp_j_1, 1), SASR( *LARpp_j, 1 ));
+	}
+}
+
+static void Coefficients_27_39 (
+	register word * LARpp_j_1,
+	register word * LARpp_j,
+	register word * LARp)
+{
+	register int i;
+	register longword ltmp;
+
+	for (i = 1; i <= 8; i++, LARpp_j_1++, LARpp_j++, LARp++) {
+		*LARp = GSM_ADD( SASR( *LARpp_j_1, 2 ), SASR( *LARpp_j, 2 ));
+		*LARp = GSM_ADD( *LARp, SASR( *LARpp_j, 1 ));
+	}
+}
+
+
+static void Coefficients_40_159 (
+	register word * LARpp_j,
+	register word * LARp)
+{
+	register int i;
+
+	for (i = 1; i <= 8; i++, LARp++, LARpp_j++)
+		*LARp = *LARpp_j;
+}
+
+/* 4.2.9.2 */
+
+static void LARp_to_rp (
+	register word * LARp)	/* [0..7] IN/OUT  */
+/*
+ *  The input of this procedure is the interpolated LARp[0..7] array.
+ *  The reflection coefficients, rp[i], are used in the analysis
+ *  filter and in the synthesis filter.
+ */
+{
+	register int 		i;
+	register word		temp;
+	register longword	ltmp;
+
+	for (i = 1; i <= 8; i++, LARp++) {
+
+		/* temp = GSM_ABS( *LARp );
+	         *
+		 * if (temp < 11059) temp <<= 1;
+		 * else if (temp < 20070) temp += 11059;
+		 * else temp = GSM_ADD( temp >> 2, 26112 );
+		 *
+		 * *LARp = *LARp < 0 ? -temp : temp;
+		 */
+
+		if (*LARp < 0) {
+			temp = *LARp == MIN_WORD ? MAX_WORD : -(*LARp);
+			*LARp = - ((temp < 11059) ? temp << 1
+				: ((temp < 20070) ? temp + 11059
+				:  GSM_ADD( temp >> 2, 26112 )));
+		} else {
+			temp  = *LARp;
+			*LARp =    (temp < 11059) ? temp << 1
+				: ((temp < 20070) ? temp + 11059
+				:  GSM_ADD( temp >> 2, 26112 ));
+		}
+	}
+}
+
+
+/* 4.2.10 */
+static void Short_term_analysis_filtering (
+	struct gsm_state * S,
+	register word	* rp,	/* [0..7]	IN	*/
+	register int 	k_n, 	/*   k_end - k_start	*/
+	register word	* s	/* [0..n-1]	IN/OUT	*/
+)
+/*
+ *  This procedure computes the short term residual signal d[..] to be fed
+ *  to the RPE-LTP loop from the s[..] signal and from the local rp[..]
+ *  array (quantized reflection coefficients).  As the call of this
+ *  procedure can be done in many ways (see the interpolation of the LAR
+ *  coefficient), it is assumed that the computation begins with index
+ *  k_start (for arrays d[..] and s[..]) and stops with index k_end
+ *  (k_start and k_end are defined in 4.2.9.1).  This procedure also
+ *  needs to keep the array u[0..7] in memory for each call.
+ */
+{
+	register word		* u = S->u;
+	register int		i;
+	register word		di, zzz, ui, sav, rpi;
+	register longword 	ltmp;
+
+	for (; k_n--; s++) {
+
+		di = sav = *s;
+
+		for (i = 0; i < 8; i++) {		/* YYY */
+
+			ui    = u[i];
+			rpi   = rp[i];
+			u[i]  = sav;
+
+			zzz   = GSM_MULT_R(rpi, di);
+			sav   = GSM_ADD(   ui,  zzz);
+
+			zzz   = GSM_MULT_R(rpi, ui);
+			di    = GSM_ADD(   di,  zzz );
+		}
+
+		*s = di;
+	}
+}
+
+#if defined(USE_FLOAT_MUL) && defined(FAST)
+
+static void Fast_Short_term_analysis_filtering (
+	struct gsm_state * S,
+	register word	* rp,	/* [0..7]	IN	*/
+	register int 	k_n, 	/*   k_end - k_start	*/
+	register word	* s	/* [0..n-1]	IN/OUT	*/
+)
+{
+	register word		* u = S->u;
+	register int		i;
+
+	float 	  uf[8],
+		 rpf[8];
+
+	register float scalef = 3.0517578125e-5;
+	register float		sav, di, temp;
+
+	for (i = 0; i < 8; ++i) {
+		uf[i]  = u[i];
+		rpf[i] = rp[i] * scalef;
+	}
+	for (; k_n--; s++) {
+		sav = di = *s;
+		for (i = 0; i < 8; ++i) {
+			register float rpfi = rpf[i];
+			register float ufi  = uf[i];
+
+			uf[i] = sav;
+			temp  = rpfi * di + ufi;
+			di   += rpfi * ufi;
+			sav   = temp;
+		}
+		*s = di;
+	}
+	for (i = 0; i < 8; ++i) u[i] = uf[i];
+}
+#endif /* ! (defined (USE_FLOAT_MUL) && defined (FAST)) */
+
+static void Short_term_synthesis_filtering (
+	struct gsm_state * S,
+	register word	* rrp,	/* [0..7]	IN	*/
+	register int	k,	/* k_end - k_start	*/
+	register word	* wt,	/* [0..k-1]	IN	*/
+	register word	* sr	/* [0..k-1]	OUT	*/
+)
+{
+	register word		* v = S->v;
+	register int		i;
+	register word		sri, tmp1, tmp2;
+	register longword	ltmp;	/* for GSM_ADD  & GSM_SUB */
+
+	while (k--) {
+		sri = *wt++;
+		for (i = 8; i--;) {
+
+			/* sri = GSM_SUB( sri, gsm_mult_r( rrp[i], v[i] ) );
+			 */
+			tmp1 = rrp[i];
+			tmp2 = v[i];
+			tmp2 =  ( tmp1 == MIN_WORD && tmp2 == MIN_WORD
+				? MAX_WORD
+				: 0x0FFFF & (( (longword)tmp1 * (longword)tmp2
+					     + 16384) >> 15)) ;
+
+			sri  = GSM_SUB( sri, tmp2 );
+
+			/* v[i+1] = GSM_ADD( v[i], gsm_mult_r( rrp[i], sri ) );
+			 */
+			tmp1  = ( tmp1 == MIN_WORD && sri == MIN_WORD
+				? MAX_WORD
+				: 0x0FFFF & (( (longword)tmp1 * (longword)sri
+					     + 16384) >> 15)) ;
+
+			v[i+1] = GSM_ADD( v[i], tmp1);
+		}
+		*sr++ = v[0] = sri;
+	}
+}
+
+
+#if defined(FAST) && defined(USE_FLOAT_MUL)
+
+static void Fast_Short_term_synthesis_filtering (
+	struct gsm_state * S,
+	register word	* rrp,	/* [0..7]	IN	*/
+	register int	k,	/* k_end - k_start	*/
+	register word	* wt,	/* [0..k-1]	IN	*/
+	register word	* sr	/* [0..k-1]	OUT	*/
+)
+{
+	register word		* v = S->v;
+	register int		i;
+
+	float va[9], rrpa[8];
+	register float scalef = 3.0517578125e-5, temp;
+
+	for (i = 0; i < 8; ++i) {
+		va[i]   = v[i];
+		rrpa[i] = (float)rrp[i] * scalef;
+	}
+	while (k--) {
+		register float sri = *wt++;
+		for (i = 8; i--;) {
+			sri -= rrpa[i] * va[i];
+			if     (sri < -32768.) sri = -32768.;
+			else if (sri > 32767.) sri =  32767.;
+
+			temp = va[i] + rrpa[i] * sri;
+			if     (temp < -32768.) temp = -32768.;
+			else if (temp > 32767.) temp =  32767.;
+			va[i+1] = temp;
+		}
+		*sr++ = va[0] = sri;
+	}
+	for (i = 0; i < 9; ++i) v[i] = va[i];
+}
+
+#endif /* defined(FAST) && defined(USE_FLOAT_MUL) */
+
+void Gsm_Short_Term_Analysis_Filter (
+
+	struct gsm_state * S,
+
+	word	* LARc,		/* coded log area ratio [0..7]  IN	*/
+	word	* s		/* signal [0..159]		IN/OUT	*/
+)
+{
+	word		* LARpp_j	= S->LARpp[ S->j      ];
+	word		* LARpp_j_1	= S->LARpp[ S->j ^= 1 ];
+
+	word		LARp[8];
+
+#undef	FILTER
+#if 	defined(FAST) && defined(USE_FLOAT_MUL)
+# 	define	FILTER 	(* (S->fast			\
+			   ? Fast_Short_term_analysis_filtering	\
+		    	   : Short_term_analysis_filtering	))
+
+#else
+# 	define	FILTER	Short_term_analysis_filtering
+#endif
+
+	Decoding_of_the_coded_Log_Area_Ratios( LARc, LARpp_j );
+
+	Coefficients_0_12(  LARpp_j_1, LARpp_j, LARp );
+	LARp_to_rp( LARp );
+	FILTER( S, LARp, 13, s);
+
+	Coefficients_13_26( LARpp_j_1, LARpp_j, LARp);
+	LARp_to_rp( LARp );
+	FILTER( S, LARp, 14, s + 13);
+
+	Coefficients_27_39( LARpp_j_1, LARpp_j, LARp);
+	LARp_to_rp( LARp );
+	FILTER( S, LARp, 13, s + 27);
+
+	Coefficients_40_159( LARpp_j, LARp);
+	LARp_to_rp( LARp );
+	FILTER( S, LARp, 120, s + 40);
+}
+
+void Gsm_Short_Term_Synthesis_Filter (
+	struct gsm_state * S,
+
+	word	* LARcr,	/* received log area ratios [0..7] IN  */
+	word	* wt,		/* received d [0..159]		   IN  */
+
+	word	* s		/* signal   s [0..159]		  OUT  */
+)
+{
+	word		* LARpp_j	= S->LARpp[ S->j     ];
+	word		* LARpp_j_1	= S->LARpp[ S->j ^=1 ];
+
+	word		LARp[8];
+
+#undef	FILTER
+#if 	defined(FAST) && defined(USE_FLOAT_MUL)
+
+# 	define	FILTER 	(* (S->fast			\
+			   ? Fast_Short_term_synthesis_filtering	\
+		    	   : Short_term_synthesis_filtering	))
+#else
+#	define	FILTER	Short_term_synthesis_filtering
+#endif
+
+	Decoding_of_the_coded_Log_Area_Ratios( LARcr, LARpp_j );
+
+	Coefficients_0_12( LARpp_j_1, LARpp_j, LARp );
+	LARp_to_rp( LARp );
+	FILTER( S, LARp, 13, wt, s );
+
+	Coefficients_13_26( LARpp_j_1, LARpp_j, LARp);
+	LARp_to_rp( LARp );
+	FILTER( S, LARp, 14, wt + 13, s + 13 );
+
+	Coefficients_27_39( LARpp_j_1, LARpp_j, LARp);
+	LARp_to_rp( LARp );
+	FILTER( S, LARp, 13, wt + 27, s + 27 );
+
+	Coefficients_40_159( LARpp_j, LARp );
+	LARp_to_rp( LARp );
+	FILTER(S, LARp, 120, wt + 40, s + 40);
+}
--- /dev/null
+++ b/libgsm/table.c
@@ -1,0 +1,63 @@
+/*
+ * Copyright 1992 by Jutta Degener and Carsten Bormann, Technische
+ * Universitaet Berlin.  See the accompanying file "COPYRIGHT" for
+ * details.  THERE IS ABSOLUTELY NO WARRANTY FOR THIS SOFTWARE.
+ */
+
+/* $Header: /cvsroot/sox/sox/libgsm/table.c,v 1.1 2007/09/06 16:50:56 cbagwell Exp $ */
+
+/*  Most of these tables are inlined at their point of use.
+ */
+
+/*  4.4 TABLES USED IN THE FIXED POINT IMPLEMENTATION OF THE RPE-LTP
+ *      CODER AND DECODER
+ *
+ *	(Most of them inlined, so watch out.)
+ */
+
+#define	GSM_TABLE_C
+#include "private.h"
+#include	"gsm.h"
+
+/*  Table 4.1  Quantization of the Log.-Area Ratios
+ */
+/* i 		     1      2      3        4      5      6        7       8 */
+word gsm_A[8]   = {20480, 20480, 20480,  20480,  13964,  15360,   8534,  9036};
+word gsm_B[8]   = {    0,     0,  2048,  -2560,     94,  -1792,   -341, -1144};
+word gsm_MIC[8] = { -32,   -32,   -16,    -16,     -8,     -8,     -4,    -4 };
+word gsm_MAC[8] = {  31,    31,    15,     15,      7,      7,      3,     3 };
+
+
+/*  Table 4.2  Tabulation  of 1/A[1..8]
+ */
+word gsm_INVA[8]={ 13107, 13107,  13107, 13107,  19223, 17476,  31454, 29708 };
+
+
+/*   Table 4.3a  Decision level of the LTP gain quantizer
+ */
+/*  bc		      0	        1	  2	     3			*/
+word gsm_DLB[4] = {  6554,    16384,	26214,	   32767	};
+
+
+/*   Table 4.3b   Quantization levels of the LTP gain quantizer
+ */
+/* bc		      0          1        2          3			*/
+word gsm_QLB[4] = {  3277,    11469,	21299,	   32767	};
+
+
+/*   Table 4.4	 Coefficients of the weighting filter
+ */
+/* i		    0      1   2    3   4      5      6     7   8   9    10  */
+word gsm_H[11] = {-134, -374, 0, 2054, 5741, 8192, 5741, 2054, 0, -374, -134 };
+
+
+/*   Table 4.5 	 Normalized inverse mantissa used to compute xM/xmax 
+ */
+/* i		 	0        1    2      3      4      5     6      7   */
+word gsm_NRFAC[8] = { 29128, 26215, 23832, 21846, 20165, 18725, 17476, 16384 };
+
+
+/*   Table 4.6	 Normalized direct mantissa used to compute xM/xmax
+ */
+/* i                  0      1       2      3      4      5      6      7   */
+word gsm_FAC[8]	= { 18431, 20479, 22527, 24575, 26623, 28671, 30719, 32767 };
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -1,8 +1,5 @@
 ## Process this file with automake to produce Makefile.in
 
-SUBDIRS = libgsm
-DIST_SUBDIRS = libgsm
-
 RM = rm -f 
 
 AM_CPPFLAGS = -DLADSPA_PATH="\"@LADSPA_PATH@\"" -DPKGLIBDIR="\"$(pkglibdir)\""
--- a/src/gsm.c
+++ b/src/gsm.c
@@ -31,7 +31,7 @@
 #ifdef EXTERNAL_GSM
 #include <gsm/gsm.h>
 #else
-#include "libgsm/gsm.h"
+#include "../libgsm/gsm.h"
 #endif
 
 #include <errno.h>
--- a/src/wav.c
+++ b/src/wav.c
@@ -26,7 +26,7 @@
 #ifdef EXTERNAL_GSM
 #include <gsm/gsm.h>
 #else
-#include "libgsm/gsm.h"
+#include "../libgsm/gsm.h"
 #endif
 
 /* To allow padding to samplesPerBlock. Works, but currently never true. */