Import libdect

Signed-off-by: Patrick McHardy <kaber@trash.net>

9 files changed, 1833 insertions, 0 deletions

diff --git a/src/ccitt-adpcm/README b/src/ccitt-adpcm/README
new file mode 100644
index 0000000..23b0e7d
--- /dev/null
+++ b/src/ccitt-adpcm/README
@@ -0,0 +1,94 @@
+The files in this directory comprise ANSI-C language reference implementations
+of the CCITT (International Telegraph and Telephone Consultative Committee)
+G.711, G.721 and G.723 voice compressions.  They have been tested on Sun
+SPARCstations and passed 82 out of 84 test vectors published by CCITT
+(Dec. 20, 1988) for G.721 and G.723.  [The two remaining test vectors,
+which the G.721 decoder implementation for u-law samples did not pass,
+may be in error because they are identical to two other vectors for G.723_40.]
+
+This source code is released by Sun Microsystems, Inc. to the public domain.
+Please give your acknowledgement in product literature if this code is used
+in your product implementation.
+
+Sun Microsystems supports some CCITT audio formats in Solaris 2.0 system
+software.  However, Sun's implementations have been optimized for higher
+performance on SPARCstations.
+
+
+The source files for CCITT conversion routines in this directory are:
+
+	g72x.h		header file for g721.c, g723_24.c and g723_40.c
+	g711.c		CCITT G.711 u-law and A-law compression
+	g72x.c		common denominator of G.721 and G.723 ADPCM codes
+	g721.c		CCITT G.721 32Kbps ADPCM coder (with g72x.c)
+	g723_24.c	CCITT G.723 24Kbps ADPCM coder (with g72x.c)
+	g723_40.c	CCITT G.723 40Kbps ADPCM coder (with g72x.c)
+
+
+Simple conversions between u-law, A-law, and 16-bit linear PCM are invoked
+as follows:
+
+	unsigned char		ucode, acode;
+	short			pcm_val;
+
+	ucode = linear2ulaw(pcm_val);
+	ucode = alaw2ulaw(acode);
+
+	acode = linear2alaw(pcm_val);
+	acode = ulaw2alaw(ucode);
+
+	pcm_val = ulaw2linear(ucode);
+	pcm_val = alaw2linear(acode);
+
+
+The other CCITT compression routines are invoked as follows:
+
+	#include "g72x.h"
+
+	struct g72x_state	state;
+	int			sample, code;
+
+	g72x_init_state(&state);
+	code = {g721,g723_24,g723_40}_encoder(sample, coding, &state);
+	sample = {g721,g723_24,g723_40}_decoder(code, coding, &state);
+
+where
+	coding = AUDIO_ENCODING_ULAW	for 8-bit u-law samples
+		 AUDIO_ENCODING_ALAW	for 8-bit A-law samples
+		 AUDIO_ENCODING_LINEAR	for 16-bit linear PCM samples
+
+
+
+This directory also includes the following sample programs:
+
+	encode.c	CCITT ADPCM encoder
+	decode.c	CCITT ADPCM decoder
+	Makefile	makefile for the sample programs
+
+
+The sample programs contain examples of how to call the various compression
+routines and pack/unpack the bits.  The sample programs read byte streams from
+stdin and write to stdout.  The input/output data is raw data (no file header
+or other identifying information is embedded).  The sample programs are
+invoked as follows:
+
+	encode [-3|4|5] [-a|u|l] <infile >outfile
+	decode [-3|4|5] [-a|u|l] <infile >outfile
+where:
+	-3	encode to (decode from) G.723 24kbps (3-bit) data
+	-4	encode to (decode from) G.721 32kbps (4-bit) data [the default]
+	-5	encode to (decode from) G.723 40kbps (5-bit) data
+	-a	encode from (decode to) A-law data
+	-u	encode from (decode to) u-law data [the default]
+	-l	encode from (decode to) 16-bit linear data
+
+Examples:
+	# Read 16-bit linear and output G.721
+	encode -4 -l <pcmfile >g721file
+
+	# Read 40Kbps G.723 and output A-law
+	decode -5 -a <g723file >alawfile
+
+	# Compress and then decompress u-law data using 24Kbps G.723
+	encode -3 <ulawin | deoced -3 >ulawout
+
diff --git a/src/ccitt-adpcm/decode.c b/src/ccitt-adpcm/decode.c
new file mode 100644
index 0000000..cf8c739
--- /dev/null
+++ b/src/ccitt-adpcm/decode.c
@@ -0,0 +1,113 @@
+/*
+ * decode.c
+ *
+ * CCITT ADPCM decoder
+ *
+ * Usage : decode [-3|4|5] [-a|u|l] < infile > outfile
+ */
+#include <stdio.h>
+#include "g72x.h"
+
+
+/*
+ * Unpack input codes and pass them back as bytes.
+ * Returns 1 if there is residual input, returns -1 if eof, else returns 0.
+ */
+int
+unpack_input(
+	unsigned char		*code,
+	int			bits)
+{
+	static unsigned int	in_buffer = 0;
+	static int		in_bits = 0;
+	unsigned char		in_byte;
+
+	if (in_bits < bits) {
+		if (fread(&in_byte, sizeof (char), 1, stdin) != 1) {
+			*code = 0;
+			return (-1);
+		}
+		in_buffer |= (in_byte << in_bits);
+		in_bits += 8;
+	}
+	*code = in_buffer & ((1 << bits) - 1);
+	in_buffer >>= bits;
+	in_bits -= bits;
+	return (in_bits > 0);
+}
+
+
+main(
+	int			argc,
+	char			**argv)
+{
+	short			sample;
+	unsigned char		code;
+	int			n;
+	struct g72x_state	state;
+	int			out_coding;
+	int			out_size;
+	int			(*dec_routine)();
+	int			dec_bits;
+
+	g72x_init_state(&state);
+	out_coding = AUDIO_ENCODING_ULAW;
+	out_size = sizeof (char);
+	dec_routine = g721_decoder;
+	dec_bits = 4;
+
+	/* Process encoding argument, if any */
+	while ((argc > 1) && (argv[1][0] == '-')) {
+		switch (argv[1][1]) {
+		case '3':
+			dec_routine = g723_24_decoder;
+			dec_bits = 3;
+			break;
+		case '4':
+			dec_routine = g721_decoder;
+			dec_bits = 4;
+			break;
+		case '5':
+			dec_routine = g723_40_decoder;
+			dec_bits = 5;
+			break;
+		case 'u':
+			out_coding = AUDIO_ENCODING_ULAW;
+			out_size = sizeof (char);
+			break;
+		case 'a':
+			out_coding = AUDIO_ENCODING_ALAW;
+			out_size = sizeof (char);
+			break;
+		case 'l':
+			out_coding = AUDIO_ENCODING_LINEAR;
+			out_size = sizeof (short);
+			break;
+		default:
+fprintf(stderr, "CCITT ADPCM Decoder -- usage:\n");
+fprintf(stderr, "\tdecode [-3|4|5] [-a|u|l] < infile > outfile\n");
+fprintf(stderr, "where:\n");
+fprintf(stderr, "\t-3\tProcess G.723 24kbps (3-bit) input data\n");
+fprintf(stderr, "\t-4\tProcess G.721 32kbps (4-bit) input data [default]\n");
+fprintf(stderr, "\t-5\tProcess G.723 40kbps (5-bit) input data\n");
+fprintf(stderr, "\t-a\tGenerate 8-bit A-law data\n");
+fprintf(stderr, "\t-u\tGenerate 8-bit u-law data [default]\n");
+fprintf(stderr, "\t-l\tGenerate 16-bit linear PCM data\n");
+			exit(1);
+		}
+		argc--;
+		argv++;
+	}
+
+	/* Read and unpack input codes and process them */
+	while (unpack_input(&code, dec_bits) >= 0) {
+		sample = (*dec_routine)(code, out_coding, &state);
+		if (out_size == 2) {
+			fwrite(&sample, out_size, 1, stdout);
+		} else {
+			code = (unsigned char)sample;
+			fwrite(&code, out_size, 1, stdout);
+		}
+	}
+	fclose(stdout);
+}
diff --git a/src/ccitt-adpcm/encode.c b/src/ccitt-adpcm/encode.c
new file mode 100644
index 0000000..571fbe8
--- /dev/null
+++ b/src/ccitt-adpcm/encode.c
@@ -0,0 +1,119 @@
+/*
+ * encode.c
+ *
+ * CCITT ADPCM encoder
+ *
+ * Usage : encode [-3|4|5] [-a|u|l] < infile > outfile
+ */
+#include <stdio.h>
+#include "g72x.h"
+
+
+/*
+ * Pack output codes into bytes and write them to stdout.
+ * Returns 1 if there is residual output, else returns 0.
+ */
+int
+pack_output(
+	unsigned		code,
+	int			bits)
+{
+	static unsigned int	out_buffer = 0;
+	static int		out_bits = 0;
+	unsigned char		out_byte;
+
+	out_buffer |= (code << out_bits);
+	out_bits += bits;
+	if (out_bits >= 8) {
+		out_byte = out_buffer & 0xff;
+		out_bits -= 8;
+		out_buffer >>= 8;
+		fwrite(&out_byte, sizeof (char), 1, stdout);
+	}
+	return (out_bits > 0);
+}
+
+
+main(
+	int			argc,
+	char			**argv)
+{
+	struct g72x_state	state;
+	unsigned char		sample_char;
+	short			sample_short;
+	unsigned char		code;
+	int			resid;
+	int			in_coding;
+	int			in_size;
+	unsigned		*in_buf;
+	int			(*enc_routine)();
+	int			enc_bits;
+
+	g72x_init_state(&state);
+
+	/* Set defaults to u-law input, G.721 output */
+	in_coding = AUDIO_ENCODING_ULAW;
+	in_size = sizeof (char);
+	in_buf = (unsigned *)&sample_char;
+	enc_routine = g721_encoder;
+	enc_bits = 4;
+
+	/* Process encoding argument, if any */
+	while ((argc > 1) && (argv[1][0] == '-')) {
+		switch (argv[1][1]) {
+		case '3':
+			enc_routine = g723_24_encoder;
+			enc_bits = 3;
+			break;
+		case '4':
+			enc_routine = g721_encoder;
+			enc_bits = 4;
+			break;
+		case '5':
+			enc_routine = g723_40_encoder;
+			enc_bits = 5;
+			break;
+		case 'u':
+			in_coding = AUDIO_ENCODING_ULAW;
+			in_size = sizeof (char);
+			in_buf = (unsigned *)&sample_char;
+			break;
+		case 'a':
+			in_coding = AUDIO_ENCODING_ALAW;
+			in_size = sizeof (char);
+			in_buf = (unsigned *)&sample_char;
+			break;
+		case 'l':
+			in_coding = AUDIO_ENCODING_LINEAR;
+			in_size = sizeof (short);
+			in_buf = (unsigned *)&sample_short;
+			break;
+		default:
+fprintf(stderr, "CCITT ADPCM Encoder -- usage:\n");
+fprintf(stderr, "\tencode [-3|4|5] [-a|u|l] < infile > outfile\n");
+fprintf(stderr, "where:\n");
+fprintf(stderr, "\t-3\tGenerate G.723 24kbps (3-bit) data\n");
+fprintf(stderr, "\t-4\tGenerate G.721 32kbps (4-bit) data [default]\n");
+fprintf(stderr, "\t-5\tGenerate G.723 40kbps (5-bit) data\n");
+fprintf(stderr, "\t-a\tProcess 8-bit A-law input data\n");
+fprintf(stderr, "\t-u\tProcess 8-bit u-law input data [default]\n");
+fprintf(stderr, "\t-l\tProcess 16-bit linear PCM input data\n");
+			exit(1);
+		}
+		argc--;
+		argv++;
+	}
+
+	/* Read input file and process */
+	while (fread(in_buf, in_size, 1, stdin) == 1) {
+		code = (*enc_routine)(in_size == 2 ? sample_short : sample_char,
+		    in_coding, &state);
+		resid = pack_output(code, enc_bits);
+	}
+
+	/* Write zero codes until all residual codes are written out */
+	while (resid) {
+		resid = pack_output(0, enc_bits);
+	}
+	fclose(stdout);
+}
diff --git a/src/ccitt-adpcm/g711.c b/src/ccitt-adpcm/g711.c
new file mode 100644
index 0000000..f9eab50
--- /dev/null
+++ b/src/ccitt-adpcm/g711.c
@@ -0,0 +1,285 @@
+/*
+ * This source code is a product of Sun Microsystems, Inc. and is provided
+ * for unrestricted use.  Users may copy or modify this source code without
+ * charge.
+ *
+ * SUN SOURCE CODE IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING
+ * THE WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
+ *
+ * Sun source code is provided with no support and without any obligation on
+ * the part of Sun Microsystems, Inc. to assist in its use, correction,
+ * modification or enhancement.
+ *
+ * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
+ * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY THIS SOFTWARE
+ * OR ANY PART THEREOF.
+ *
+ * In no event will Sun Microsystems, Inc. be liable for any lost revenue
+ * or profits or other special, indirect and consequential damages, even if
+ * Sun has been advised of the possibility of such damages.
+ *
+ * Sun Microsystems, Inc.
+ * 2550 Garcia Avenue
+ * Mountain View, California  94043
+ */
+
+#include "g72x.h"
+
+/*
+ * g711.c
+ *
+ * u-law, A-law and linear PCM conversions.
+ */
+#define	SIGN_BIT	(0x80)		/* Sign bit for a A-law byte. */
+#define	QUANT_MASK	(0xf)		/* Quantization field mask. */
+#define	NSEGS		(8)		/* Number of A-law segments. */
+#define	SEG_SHIFT	(4)		/* Left shift for segment number. */
+#define	SEG_MASK	(0x70)		/* Segment field mask. */
+
+static short seg_end[8] = {0xFF, 0x1FF, 0x3FF, 0x7FF,
+			    0xFFF, 0x1FFF, 0x3FFF, 0x7FFF};
+
+/* copy from CCITT G.711 specifications */
+unsigned char _u2a[128] = {			/* u- to A-law conversions */
+	1,	1,	2,	2,	3,	3,	4,	4,
+	5,	5,	6,	6,	7,	7,	8,	8,
+	9,	10,	11,	12,	13,	14,	15,	16,
+	17,	18,	19,	20,	21,	22,	23,	24,
+	25,	27,	29,	31,	33,	34,	35,	36,
+	37,	38,	39,	40,	41,	42,	43,	44,
+	46,	48,	49,	50,	51,	52,	53,	54,
+	55,	56,	57,	58,	59,	60,	61,	62,
+	64,	65,	66,	67,	68,	69,	70,	71,
+	72,	73,	74,	75,	76,	77,	78,	79,
+	81,	82,	83,	84,	85,	86,	87,	88,
+	89,	90,	91,	92,	93,	94,	95,	96,
+	97,	98,	99,	100,	101,	102,	103,	104,
+	105,	106,	107,	108,	109,	110,	111,	112,
+	113,	114,	115,	116,	117,	118,	119,	120,
+	121,	122,	123,	124,	125,	126,	127,	128};
+
+unsigned char _a2u[128] = {			/* A- to u-law conversions */
+	1,	3,	5,	7,	9,	11,	13,	15,
+	16,	17,	18,	19,	20,	21,	22,	23,
+	24,	25,	26,	27,	28,	29,	30,	31,
+	32,	32,	33,	33,	34,	34,	35,	35,
+	36,	37,	38,	39,	40,	41,	42,	43,
+	44,	45,	46,	47,	48,	48,	49,	49,
+	50,	51,	52,	53,	54,	55,	56,	57,
+	58,	59,	60,	61,	62,	63,	64,	64,
+	65,	66,	67,	68,	69,	70,	71,	72,
+	73,	74,	75,	76,	77,	78,	79,	79,
+	80,	81,	82,	83,	84,	85,	86,	87,
+	88,	89,	90,	91,	92,	93,	94,	95,
+	96,	97,	98,	99,	100,	101,	102,	103,
+	104,	105,	106,	107,	108,	109,	110,	111,
+	112,	113,	114,	115,	116,	117,	118,	119,
+	120,	121,	122,	123,	124,	125,	126,	127};
+
+static int
+search(
+	int		val,
+	short		*table,
+	int		size)
+{
+	int		i;
+
+	for (i = 0; i < size; i++) {
+		if (val <= *table++)
+			return (i);
+	}
+	return (size);
+}
+
+/*
+ * linear2alaw() - Convert a 16-bit linear PCM value to 8-bit A-law
+ *
+ * linear2alaw() accepts an 16-bit integer and encodes it as A-law data.
+ *
+ *		Linear Input Code	Compressed Code
+ *	------------------------	---------------
+ *	0000000wxyza			000wxyz
+ *	0000001wxyza			001wxyz
+ *	000001wxyzab			010wxyz
+ *	00001wxyzabc			011wxyz
+ *	0001wxyzabcd			100wxyz
+ *	001wxyzabcde			101wxyz
+ *	01wxyzabcdef			110wxyz
+ *	1wxyzabcdefg			111wxyz
+ *
+ * For further information see John C. Bellamy's Digital Telephony, 1982,
+ * John Wiley & Sons, pps 98-111 and 472-476.
+ */
+unsigned char
+linear2alaw(
+	int		pcm_val)	/* 2's complement (16-bit range) */
+{
+	int		mask;
+	int		seg;
+	unsigned char	aval;
+
+	if (pcm_val >= 0) {
+		mask = 0xD5;		/* sign (7th) bit = 1 */
+	} else {
+		mask = 0x55;		/* sign bit = 0 */
+		pcm_val = -pcm_val - 8;
+	}
+
+	/* Convert the scaled magnitude to segment number. */
+	seg = search(pcm_val, seg_end, 8);
+
+	/* Combine the sign, segment, and quantization bits. */
+
+	if (seg >= 8)		/* out of range, return maximum value. */
+		return (0x7F ^ mask);
+	else {
+		aval = seg << SEG_SHIFT;
+		if (seg < 2)
+			aval |= (pcm_val >> 4) & QUANT_MASK;
+		else
+			aval |= (pcm_val >> (seg + 3)) & QUANT_MASK;
+		return (aval ^ mask);
+	}
+}
+
+/*
+ * alaw2linear() - Convert an A-law value to 16-bit linear PCM
+ *
+ */
+int
+alaw2linear(
+	unsigned char	a_val)
+{
+	int		t;
+	int		seg;
+
+	a_val ^= 0x55;
+
+	t = (a_val & QUANT_MASK) << 4;
+	seg = ((unsigned)a_val & SEG_MASK) >> SEG_SHIFT;
+	switch (seg) {
+	case 0:
+		t += 8;
+		break;
+	case 1:
+		t += 0x108;
+		break;
+	default:
+		t += 0x108;
+		t <<= seg - 1;
+	}
+	return ((a_val & SIGN_BIT) ? t : -t);
+}
+
+#define	BIAS		(0x84)		/* Bias for linear code. */
+
+/*
+ * linear2ulaw() - Convert a linear PCM value to u-law
+ *
+ * In order to simplify the encoding process, the original linear magnitude
+ * is biased by adding 33 which shifts the encoding range from (0 - 8158) to
+ * (33 - 8191). The result can be seen in the following encoding table:
+ *
+ *	Biased Linear Input Code	Compressed Code
+ *	------------------------	---------------
+ *	00000001wxyza			000wxyz
+ *	0000001wxyzab			001wxyz
+ *	000001wxyzabc			010wxyz
+ *	00001wxyzabcd			011wxyz
+ *	0001wxyzabcde			100wxyz
+ *	001wxyzabcdef			101wxyz
+ *	01wxyzabcdefg			110wxyz
+ *	1wxyzabcdefgh			111wxyz
+ *
+ * Each biased linear code has a leading 1 which identifies the segment
+ * number. The value of the segment number is equal to 7 minus the number
+ * of leading 0's. The quantization interval is directly available as the
+ * four bits wxyz.  * The trailing bits (a - h) are ignored.
+ *
+ * Ordinarily the complement of the resulting code word is used for
+ * transmission, and so the code word is complemented before it is returned.
+ *
+ * For further information see John C. Bellamy's Digital Telephony, 1982,
+ * John Wiley & Sons, pps 98-111 and 472-476.
+ */
+unsigned char
+linear2ulaw(
+	int		pcm_val)	/* 2's complement (16-bit range) */
+{
+	int		mask;
+	int		seg;
+	unsigned char	uval;
+
+	/* Get the sign and the magnitude of the value. */
+	if (pcm_val < 0) {
+		pcm_val = BIAS - pcm_val;
+		mask = 0x7F;
+	} else {
+		pcm_val += BIAS;
+		mask = 0xFF;
+	}
+
+	/* Convert the scaled magnitude to segment number. */
+	seg = search(pcm_val, seg_end, 8);
+
+	/*
+	 * Combine the sign, segment, quantization bits;
+	 * and complement the code word.
+	 */
+	if (seg >= 8)		/* out of range, return maximum value. */
+		return (0x7F ^ mask);
+	else {
+		uval = (seg << 4) | ((pcm_val >> (seg + 3)) & 0xF);
+		return (uval ^ mask);
+	}
+
+}
+
+/*
+ * ulaw2linear() - Convert a u-law value to 16-bit linear PCM
+ *
+ * First, a biased linear code is derived from the code word. An unbiased
+ * output can then be obtained by subtracting 33 from the biased code.
+ *
+ * Note that this function expects to be passed the complement of the
+ * original code word. This is in keeping with ISDN conventions.
+ */
+int
+ulaw2linear(
+	unsigned char	u_val)
+{
+	int		t;
+
+	/* Complement to obtain normal u-law value. */
+	u_val = ~u_val;
+
+	/*
+	 * Extract and bias the quantization bits. Then
+	 * shift up by the segment number and subtract out the bias.
+	 */
+	t = ((u_val & QUANT_MASK) << 3) + BIAS;
+	t <<= ((unsigned)u_val & SEG_MASK) >> SEG_SHIFT;
+
+	return ((u_val & SIGN_BIT) ? (BIAS - t) : (t - BIAS));
+}
+
+/* A-law to u-law conversion */
+unsigned char
+alaw2ulaw(
+	unsigned char	aval)
+{
+	aval &= 0xff;
+	return ((aval & 0x80) ? (0xFF ^ _a2u[aval ^ 0xD5]) :
+	    (0x7F ^ _a2u[aval ^ 0x55]));
+}
+
+/* u-law to A-law conversion */
+unsigned char
+ulaw2alaw(
+	unsigned char	uval)
+{
+	uval &= 0xff;
+	return ((uval & 0x80) ? (0xD5 ^ (_u2a[0xFF ^ uval] - 1)) :
+	    (0x55 ^ (_u2a[0x7F ^ uval] - 1)));
+}
diff --git a/src/ccitt-adpcm/g721.c b/src/ccitt-adpcm/g721.c
new file mode 100644
index 0000000..445f177
--- /dev/null
+++ b/src/ccitt-adpcm/g721.c
@@ -0,0 +1,173 @@
+/*
+ * This source code is a product of Sun Microsystems, Inc. and is provided
+ * for unrestricted use.  Users may copy or modify this source code without
+ * charge.
+ *
+ * SUN SOURCE CODE IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING
+ * THE WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
+ *
+ * Sun source code is provided with no support and without any obligation on
+ * the part of Sun Microsystems, Inc. to assist in its use, correction,
+ * modification or enhancement.
+ *
+ * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
+ * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY THIS SOFTWARE
+ * OR ANY PART THEREOF.
+ *
+ * In no event will Sun Microsystems, Inc. be liable for any lost revenue
+ * or profits or other special, indirect and consequential damages, even if
+ * Sun has been advised of the possibility of such damages.
+ *
+ * Sun Microsystems, Inc.
+ * 2550 Garcia Avenue
+ * Mountain View, California  94043
+ */
+
+/*
+ * g721.c
+ *
+ * Description:
+ *
+ * g721_encoder(), g721_decoder()
+ *
+ * These routines comprise an implementation of the CCITT G.721 ADPCM
+ * coding algorithm.  Essentially, this implementation is identical to
+ * the bit level description except for a few deviations which
+ * take advantage of work station attributes, such as hardware 2's
+ * complement arithmetic and large memory.  Specifically, certain time
+ * consuming operations such as multiplications are replaced
+ * with lookup tables and software 2's complement operations are
+ * replaced with hardware 2's complement.
+ *
+ * The deviation from the bit level specification (lookup tables)
+ * preserves the bit level performance specifications.
+ *
+ * As outlined in the G.721 Recommendation, the algorithm is broken
+ * down into modules.  Each section of code below is preceded by
+ * the name of the module which it is implementing.
+ *
+ */
+#include "g72x.h"
+
+static short qtab_721[7] = {-124, 80, 178, 246, 300, 349, 400};
+/*
+ * Maps G.721 code word to reconstructed scale factor normalized log
+ * magnitude values.
+ */
+static short	_dqlntab[16] = {-2048, 4, 135, 213, 273, 323, 373, 425,
+				425, 373, 323, 273, 213, 135, 4, -2048};
+
+/* Maps G.721 code word to log of scale factor multiplier. */
+static short	_witab[16] = {-12, 18, 41, 64, 112, 198, 355, 1122,
+				1122, 355, 198, 112, 64, 41, 18, -12};
+/*
+ * Maps G.721 code words to a set of values whose long and short
+ * term averages are computed and then compared to give an indication
+ * how stationary (steady state) the signal is.
+ */
+static short	_fitab[16] = {0, 0, 0, 0x200, 0x200, 0x200, 0x600, 0xE00,
+				0xE00, 0x600, 0x200, 0x200, 0x200, 0, 0, 0};
+
+/*
+ * g721_encoder()
+ *
+ * Encodes the input vale of linear PCM, A-law or u-law data sl and returns
+ * the resulting code. -1 is returned for unknown input coding value.
+ */
+int
+g721_encoder(
+	int		sl,
+	int		in_coding,
+	struct g72x_state *state_ptr)
+{
+	short		sezi, se, sez;		/* ACCUM */
+	short		d;			/* SUBTA */
+	short		sr;			/* ADDB */
+	short		y;			/* MIX */
+	short		dqsez;			/* ADDC */
+	short		dq, i;
+
+	switch (in_coding) {	/* linearize input sample to 14-bit PCM */
+	case AUDIO_ENCODING_ALAW:
+		sl = alaw2linear(sl) >> 2;
+		break;
+	case AUDIO_ENCODING_ULAW:
+		sl = ulaw2linear(sl) >> 2;
+		break;
+	case AUDIO_ENCODING_LINEAR:
+		sl >>= 2;			/* 14-bit dynamic range */
+		break;
+	default:
+		return (-1);
+	}
+
+	sezi = predictor_zero(state_ptr);
+	sez = sezi >> 1;
+	se = (sezi + predictor_pole(state_ptr)) >> 1;	/* estimated signal */
+
+	d = sl - se;				/* estimation difference */
+
+	/* quantize the prediction difference */
+	y = step_size(state_ptr);		/* quantizer step size */
+	i = quantize(d, y, qtab_721, 7);	/* i = ADPCM code */
+
+	dq = reconstruct(i & 8, _dqlntab[i], y);	/* quantized est diff */
+
+	sr = (dq < 0) ? se - (dq & 0x3FFF) : se + dq;	/* reconst. signal */
+
+	dqsez = sr + sez - se;			/* pole prediction diff. */
+
+	update(4, y, _witab[i] << 5, _fitab[i], dq, sr, dqsez, state_ptr);
+
+	return (i);
+}
+
+/*
+ * g721_decoder()
+ *
+ * Description:
+ *
+ * Decodes a 4-bit code of G.721 encoded data of i and
+ * returns the resulting linear PCM, A-law or u-law value.
+ * return -1 for unknown out_coding value.
+ */
+int
+g721_decoder(
+	int		i,
+	int		out_coding,
+	struct g72x_state *state_ptr)
+{
+	short		sezi, sei, sez, se;	/* ACCUM */
+	short		y;			/* MIX */
+	short		sr;			/* ADDB */
+	short		dq;
+	short		dqsez;
+
+	i &= 0x0f;			/* mask to get proper bits */
+	sezi = predictor_zero(state_ptr);
+	sez = sezi >> 1;
+	sei = sezi + predictor_pole(state_ptr);
+	se = sei >> 1;			/* se = estimated signal */
+
+	y = step_size(state_ptr);	/* dynamic quantizer step size */
+
+	dq = reconstruct(i & 0x08, _dqlntab[i], y); /* quantized diff. */
+
+	sr = (dq < 0) ? (se - (dq & 0x3FFF)) : se + dq;	/* reconst. signal */
+
+	dqsez = sr - se + sez;			/* pole prediction diff. */
+
+	update(4, y, _witab[i] << 5, _fitab[i], dq, sr, dqsez, state_ptr);
+
+	switch (out_coding) {
+	case AUDIO_ENCODING_ALAW:
+		return (tandem_adjust_alaw(sr, se, y, i, 8, qtab_721));
+	case AUDIO_ENCODING_ULAW:
+		return (tandem_adjust_ulaw(sr, se, y, i, 8, qtab_721));
+	case AUDIO_ENCODING_LINEAR:
+		return (sr << 2);	/* sr was 14-bit dynamic range */
+	default:
+		return (-1);
+	}
+}
diff --git a/src/ccitt-adpcm/g723_24.c b/src/ccitt-adpcm/g723_24.c
new file mode 100644
index 0000000..452f4da
--- /dev/null
+++ b/src/ccitt-adpcm/g723_24.c
@@ -0,0 +1,158 @@
+/*
+ * This source code is a product of Sun Microsystems, Inc. and is provided
+ * for unrestricted use.  Users may copy or modify this source code without
+ * charge.
+ *
+ * SUN SOURCE CODE IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING
+ * THE WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
+ *
+ * Sun source code is provided with no support and without any obligation on
+ * the part of Sun Microsystems, Inc. to assist in its use, correction,
+ * modification or enhancement.
+ *
+ * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
+ * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY THIS SOFTWARE
+ * OR ANY PART THEREOF.
+ *
+ * In no event will Sun Microsystems, Inc. be liable for any lost revenue
+ * or profits or other special, indirect and consequential damages, even if
+ * Sun has been advised of the possibility of such damages.
+ *
+ * Sun Microsystems, Inc.
+ * 2550 Garcia Avenue
+ * Mountain View, California  94043
+ */
+
+/*
+ * g723_24.c
+ *
+ * Description:
+ *
+ * g723_24_encoder(), g723_24_decoder()
+ *
+ * These routines comprise an implementation of the CCITT G.723 24 Kbps
+ * ADPCM coding algorithm.  Essentially, this implementation is identical to
+ * the bit level description except for a few deviations which take advantage
+ * of workstation attributes, such as hardware 2's complement arithmetic.
+ *
+ */
+#include "g72x.h"
+
+/*
+ * Maps G.723_24 code word to reconstructed scale factor normalized log
+ * magnitude values.
+ */
+static short	_dqlntab[8] = {-2048, 135, 273, 373, 373, 273, 135, -2048};
+
+/* Maps G.723_24 code word to log of scale factor multiplier. */
+static short	_witab[8] = {-128, 960, 4384, 18624, 18624, 4384, 960, -128};
+
+/*
+ * Maps G.723_24 code words to a set of values whose long and short
+ * term averages are computed and then compared to give an indication
+ * how stationary (steady state) the signal is.
+ */
+static short	_fitab[8] = {0, 0x200, 0x400, 0xE00, 0xE00, 0x400, 0x200, 0};
+
+static short qtab_723_24[3] = {8, 218, 331};
+
+/*
+ * g723_24_encoder()
+ *
+ * Encodes a linear PCM, A-law or u-law input sample and returns its 3-bit code.
+ * Returns -1 if invalid input coding value.
+ */
+int
+g723_24_encoder(
+	int		sl,
+	int		in_coding,
+	struct g72x_state *state_ptr)
+{
+	short		sei, sezi, se, sez;	/* ACCUM */
+	short		d;			/* SUBTA */
+	short		y;			/* MIX */
+	short		sr;			/* ADDB */
+	short		dqsez;			/* ADDC */
+	short		dq, i;
+
+	switch (in_coding) {	/* linearize input sample to 14-bit PCM */
+	case AUDIO_ENCODING_ALAW:
+		sl = alaw2linear(sl) >> 2;
+		break;
+	case AUDIO_ENCODING_ULAW:
+		sl = ulaw2linear(sl) >> 2;
+		break;
+	case AUDIO_ENCODING_LINEAR:
+		sl >>= 2;		/* sl of 14-bit dynamic range */
+		break;
+	default:
+		return (-1);
+	}
+
+	sezi = predictor_zero(state_ptr);
+	sez = sezi >> 1;
+	sei = sezi + predictor_pole(state_ptr);
+	se = sei >> 1;			/* se = estimated signal */
+
+	d = sl - se;			/* d = estimation diff. */
+
+	/* quantize prediction difference d */
+	y = step_size(state_ptr);	/* quantizer step size */
+	i = quantize(d, y, qtab_723_24, 3);	/* i = ADPCM code */
+	dq = reconstruct(i & 4, _dqlntab[i], y); /* quantized diff. */
+
+	sr = (dq < 0) ? se - (dq & 0x3FFF) : se + dq; /* reconstructed signal */
+
+	dqsez = sr + sez - se;		/* pole prediction diff. */
+
+	update(3, y, _witab[i], _fitab[i], dq, sr, dqsez, state_ptr);
+
+	return (i);
+}
+
+/*
+ * g723_24_decoder()
+ *
+ * Decodes a 3-bit CCITT G.723_24 ADPCM code and returns
+ * the resulting 16-bit linear PCM, A-law or u-law sample value.
+ * -1 is returned if the output coding is unknown.
+ */
+int
+g723_24_decoder(
+	int		i,
+	int		out_coding,
+	struct g72x_state *state_ptr)
+{
+	short		sezi, sei, sez, se;	/* ACCUM */
+	short		y;			/* MIX */
+	short		sr;			/* ADDB */
+	short		dq;
+	short		dqsez;
+
+	i &= 0x07;			/* mask to get proper bits */
+	sezi = predictor_zero(state_ptr);
+	sez = sezi >> 1;
+	sei = sezi + predictor_pole(state_ptr);
+	se = sei >> 1;			/* se = estimated signal */
+
+	y = step_size(state_ptr);	/* adaptive quantizer step size */
+	dq = reconstruct(i & 0x04, _dqlntab[i], y); /* unquantize pred diff */
+
+	sr = (dq < 0) ? (se - (dq & 0x3FFF)) : (se + dq); /* reconst. signal */
+
+	dqsez = sr - se + sez;			/* pole prediction diff. */
+
+	update(3, y, _witab[i], _fitab[i], dq, sr, dqsez, state_ptr);
+
+	switch (out_coding) {
+	case AUDIO_ENCODING_ALAW:
+		return (tandem_adjust_alaw(sr, se, y, i, 4, qtab_723_24));
+	case AUDIO_ENCODING_ULAW:
+		return (tandem_adjust_ulaw(sr, se, y, i, 4, qtab_723_24));
+	case AUDIO_ENCODING_LINEAR:
+		return (sr << 2);	/* sr was of 14-bit dynamic range */
+	default:
+		return (-1);
+	}
+}
diff --git a/src/ccitt-adpcm/g723_40.c b/src/ccitt-adpcm/g723_40.c
new file mode 100644
index 0000000..4858baf
--- /dev/null
+++ b/src/ccitt-adpcm/g723_40.c
@@ -0,0 +1,178 @@
+/*
+ * This source code is a product of Sun Microsystems, Inc. and is provided
+ * for unrestricted use.  Users may copy or modify this source code without
+ * charge.
+ *
+ * SUN SOURCE CODE IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING
+ * THE WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
+ *
+ * Sun source code is provided with no support and without any obligation on
+ * the part of Sun Microsystems, Inc. to assist in its use, correction,
+ * modification or enhancement.
+ *
+ * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
+ * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY THIS SOFTWARE
+ * OR ANY PART THEREOF.
+ *
+ * In no event will Sun Microsystems, Inc. be liable for any lost revenue
+ * or profits or other special, indirect and consequential damages, even if
+ * Sun has been advised of the possibility of such damages.
+ *
+ * Sun Microsystems, Inc.
+ * 2550 Garcia Avenue
+ * Mountain View, California  94043
+ */
+
+/*
+ * g723_40.c
+ *
+ * Description:
+ *
+ * g723_40_encoder(), g723_40_decoder()
+ *
+ * These routines comprise an implementation of the CCITT G.723 40Kbps
+ * ADPCM coding algorithm.  Essentially, this implementation is identical to
+ * the bit level description except for a few deviations which
+ * take advantage of workstation attributes, such as hardware 2's
+ * complement arithmetic.
+ *
+ * The deviation from the bit level specification (lookup tables),
+ * preserves the bit level performance specifications.
+ *
+ * As outlined in the G.723 Recommendation, the algorithm is broken
+ * down into modules.  Each section of code below is preceded by
+ * the name of the module which it is implementing.
+ *
+ */
+#include "g72x.h"
+
+/*
+ * Maps G.723_40 code word to ructeconstructed scale factor normalized log
+ * magnitude values.
+ */
+static short	_dqlntab[32] = {-2048, -66, 28, 104, 169, 224, 274, 318,
+				358, 395, 429, 459, 488, 514, 539, 566,
+				566, 539, 514, 488, 459, 429, 395, 358,
+				318, 274, 224, 169, 104, 28, -66, -2048};
+
+/* Maps G.723_40 code word to log of scale factor multiplier. */
+static short	_witab[32] = {448, 448, 768, 1248, 1280, 1312, 1856, 3200,
+			4512, 5728, 7008, 8960, 11456, 14080, 16928, 22272,
+			22272, 16928, 14080, 11456, 8960, 7008, 5728, 4512,
+			3200, 1856, 1312, 1280, 1248, 768, 448, 448};
+
+/*
+ * Maps G.723_40 code words to a set of values whose long and short
+ * term averages are computed and then compared to give an indication
+ * how stationary (steady state) the signal is.
+ */
+static short	_fitab[32] = {0, 0, 0, 0, 0, 0x200, 0x200, 0x200,
+			0x200, 0x200, 0x400, 0x600, 0x800, 0xA00, 0xC00, 0xC00,
+			0xC00, 0xC00, 0xA00, 0x800, 0x600, 0x400, 0x200, 0x200,
+			0x200, 0x200, 0x200, 0, 0, 0, 0, 0};
+
+static short qtab_723_40[15] = {-122, -16, 68, 139, 198, 250, 298, 339,
+				378, 413, 445, 475, 502, 528, 553};
+
+/*
+ * g723_40_encoder()
+ *
+ * Encodes a 16-bit linear PCM, A-law or u-law input sample and retuens
+ * the resulting 5-bit CCITT G.723 40Kbps code.
+ * Returns -1 if the input coding value is invalid.
+ */
+int
+g723_40_encoder(
+	int		sl,
+	int		in_coding,
+	struct g72x_state *state_ptr)
+{
+	short		sei, sezi, se, sez;	/* ACCUM */
+	short		d;			/* SUBTA */
+	short		y;			/* MIX */
+	short		sr;			/* ADDB */
+	short		dqsez;			/* ADDC */
+	short		dq, i;
+
+	switch (in_coding) {	/* linearize input sample to 14-bit PCM */
+	case AUDIO_ENCODING_ALAW:
+		sl = alaw2linear(sl) >> 2;
+		break;
+	case AUDIO_ENCODING_ULAW:
+		sl = ulaw2linear(sl) >> 2;
+		break;
+	case AUDIO_ENCODING_LINEAR:
+		sl >>= 2;		/* sl of 14-bit dynamic range */
+		break;
+	default:
+		return (-1);
+	}
+
+	sezi = predictor_zero(state_ptr);
+	sez = sezi >> 1;
+	sei = sezi + predictor_pole(state_ptr);
+	se = sei >> 1;			/* se = estimated signal */
+
+	d = sl - se;			/* d = estimation difference */
+
+	/* quantize prediction difference */
+	y = step_size(state_ptr);	/* adaptive quantizer step size */
+	i = quantize(d, y, qtab_723_40, 15);	/* i = ADPCM code */
+
+	dq = reconstruct(i & 0x10, _dqlntab[i], y);	/* quantized diff */
+
+	sr = (dq < 0) ? se - (dq & 0x7FFF) : se + dq; /* reconstructed signal */
+
+	dqsez = sr + sez - se;		/* dqsez = pole prediction diff. */
+
+	update(5, y, _witab[i], _fitab[i], dq, sr, dqsez, state_ptr);
+
+	return (i);
+}
+
+/*
+ * g723_40_decoder()
+ *
+ * Decodes a 5-bit CCITT G.723 40Kbps code and returns
+ * the resulting 16-bit linear PCM, A-law or u-law sample value.
+ * -1 is returned if the output coding is unknown.
+ */
+int
+g723_40_decoder(
+	int		i,
+	int		out_coding,
+	struct g72x_state *state_ptr)
+{
+	short		sezi, sei, sez, se;	/* ACCUM */
+	short		y;			/* MIX */
+	short		sr;			/* ADDB */
+	short		dq;
+	short		dqsez;
+
+	i &= 0x1f;			/* mask to get proper bits */
+	sezi = predictor_zero(state_ptr);
+	sez = sezi >> 1;
+	sei = sezi + predictor_pole(state_ptr);
+	se = sei >> 1;			/* se = estimated signal */
+
+	y = step_size(state_ptr);	/* adaptive quantizer step size */
+	dq = reconstruct(i & 0x10, _dqlntab[i], y);	/* estimation diff. */
+
+	sr = (dq < 0) ? (se - (dq & 0x7FFF)) : (se + dq); /* reconst. signal */
+
+	dqsez = sr - se + sez;		/* pole prediction diff. */
+
+	update(5, y, _witab[i], _fitab[i], dq, sr, dqsez, state_ptr);
+
+	switch (out_coding) {
+	case AUDIO_ENCODING_ALAW:
+		return (tandem_adjust_alaw(sr, se, y, i, 0x10, qtab_723_40));
+	case AUDIO_ENCODING_ULAW:
+		return (tandem_adjust_ulaw(sr, se, y, i, 0x10, qtab_723_40));
+	case AUDIO_ENCODING_LINEAR:
+		return (sr << 2);	/* sr was of 14-bit dynamic range */
+	default:
+		return (-1);
+	}
+}
diff --git a/src/ccitt-adpcm/g72x.c b/src/ccitt-adpcm/g72x.c
new file mode 100644
index 0000000..ca17c35
--- /dev/null
+++ b/src/ccitt-adpcm/g72x.c
@@ -0,0 +1,565 @@
+/*
+ * This source code is a product of Sun Microsystems, Inc. and is provided
+ * for unrestricted use.  Users may copy or modify this source code without
+ * charge.
+ *
+ * SUN SOURCE CODE IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING
+ * THE WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
+ *
+ * Sun source code is provided with no support and without any obligation on
+ * the part of Sun Microsystems, Inc. to assist in its use, correction,
+ * modification or enhancement.
+ *
+ * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
+ * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY THIS SOFTWARE
+ * OR ANY PART THEREOF.
+ *
+ * In no event will Sun Microsystems, Inc. be liable for any lost revenue
+ * or profits or other special, indirect and consequential damages, even if
+ * Sun has been advised of the possibility of such damages.
+ *
+ * Sun Microsystems, Inc.
+ * 2550 Garcia Avenue
+ * Mountain View, California  94043
+ */
+
+/*
+ * g72x.c
+ *
+ * Common routines for G.721 and G.723 conversions.
+ */
+
+#include <stdlib.h>
+#include "g72x.h"
+
+static short power2[15] = {1, 2, 4, 8, 0x10, 0x20, 0x40, 0x80,
+			0x100, 0x200, 0x400, 0x800, 0x1000, 0x2000, 0x4000};
+
+/*
+ * quan()
+ *
+ * quantizes the input val against the table of size short integers.
+ * It returns i if table[i - 1] <= val < table[i].
+ *
+ * Using linear search for simple coding.
+ */
+static int
+quan(
+	int		val,
+	short		*table,
+	int		size)
+{
+	int		i;
+
+	for (i = 0; i < size; i++)
+		if (val < *table++)
+			break;
+	return (i);
+}
+
+/*
+ * fmult()
+ *
+ * returns the integer product of the 14-bit integer "an" and
+ * "floating point" representation (4-bit exponent, 6-bit mantessa) "srn".
+ */
+static int
+fmult(
+	int		an,
+	int		srn)
+{
+	short		anmag, anexp, anmant;
+	short		wanexp, wanmant;
+	short		retval;
+
+	anmag = (an > 0) ? an : ((-an) & 0x1FFF);
+	anexp = quan(anmag, power2, 15) - 6;
+	anmant = (anmag == 0) ? 32 :
+	    (anexp >= 0) ? anmag >> anexp : anmag << -anexp;
+	wanexp = anexp + ((srn >> 6) & 0xF) - 13;
+
+	wanmant = (anmant * (srn & 077) + 0x30) >> 4;
+	retval = (wanexp >= 0) ? ((wanmant << wanexp) & 0x7FFF) :
+	    (wanmant >> -wanexp);
+
+	return (((an ^ srn) < 0) ? -retval : retval);
+}
+
+/*
+ * g72x_init_state()
+ *
+ * This routine initializes and/or resets the g72x_state structure
+ * pointed to by 'state_ptr'.
+ * All the initial state values are specified in the CCITT G.721 document.
+ */
+void
+g72x_init_state(
+	struct g72x_state *state_ptr)
+{
+	int		cnta;
+
+	state_ptr->yl = 34816;
+	state_ptr->yu = 544;
+	state_ptr->dms = 0;
+	state_ptr->dml = 0;
+	state_ptr->ap = 0;
+	for (cnta = 0; cnta < 2; cnta++) {
+		state_ptr->a[cnta] = 0;
+		state_ptr->pk[cnta] = 0;
+		state_ptr->sr[cnta] = 32;
+	}
+	for (cnta = 0; cnta < 6; cnta++) {
+		state_ptr->b[cnta] = 0;
+		state_ptr->dq[cnta] = 32;
+	}
+	state_ptr->td = 0;
+}
+
+/*
+ * predictor_zero()
+ *
+ * computes the estimated signal from 6-zero predictor.
+ *
+ */
+int
+predictor_zero(
+	struct g72x_state *state_ptr)
+{
+	int		i;
+	int		sezi;
+
+	sezi = fmult(state_ptr->b[0] >> 2, state_ptr->dq[0]);
+	for (i = 1; i < 6; i++)			/* ACCUM */
+		sezi += fmult(state_ptr->b[i] >> 2, state_ptr->dq[i]);
+	return (sezi);
+}
+/*
+ * predictor_pole()
+ *
+ * computes the estimated signal from 2-pole predictor.
+ *
+ */
+int
+predictor_pole(
+	struct g72x_state *state_ptr)
+{
+	return (fmult(state_ptr->a[1] >> 2, state_ptr->sr[1]) +
+	    fmult(state_ptr->a[0] >> 2, state_ptr->sr[0]));
+}
+/*
+ * step_size()
+ *
+ * computes the quantization step size of the adaptive quantizer.
+ *
+ */
+int
+step_size(
+	struct g72x_state *state_ptr)
+{
+	int		y;
+	int		dif;
+	int		al;
+
+	if (state_ptr->ap >= 256)
+		return (state_ptr->yu);
+	else {
+		y = state_ptr->yl >> 6;
+		dif = state_ptr->yu - y;
+		al = state_ptr->ap >> 2;
+		if (dif > 0)
+			y += (dif * al) >> 6;
+		else if (dif < 0)
+			y += (dif * al + 0x3F) >> 6;
+		return (y);
+	}
+}
+
+/*
+ * quantize()
+ *
+ * Given a raw sample, 'd', of the difference signal and a
+ * quantization step size scale factor, 'y', this routine returns the
+ * ADPCM codeword to which that sample gets quantized.  The step
+ * size scale factor division operation is done in the log base 2 domain
+ * as a subtraction.
+ */
+int
+quantize(
+	int		d,	/* Raw difference signal sample */
+	int		y,	/* Step size multiplier */
+	short		*table,	/* quantization table */
+	int		size)	/* table size of short integers */
+{
+	short		dqm;	/* Magnitude of 'd' */
+	short		exp;	/* Integer part of base 2 log of 'd' */
+	short		mant;	/* Fractional part of base 2 log */
+	short		dl;	/* Log of magnitude of 'd' */
+	short		dln;	/* Step size scale factor normalized log */
+	int		i;
+
+	/*
+	 * LOG
+	 *
+	 * Compute base 2 log of 'd', and store in 'dl'.
+	 */
+	dqm = abs(d);
+	exp = quan(dqm >> 1, power2, 15);
+	mant = ((dqm << 7) >> exp) & 0x7F;	/* Fractional portion. */
+	dl = (exp << 7) + mant;
+
+	/*
+	 * SUBTB
+	 *
+	 * "Divide" by step size multiplier.
+	 */
+	dln = dl - (y >> 2);
+
+	/*
+	 * QUAN
+	 *
+	 * Obtain codword i for 'd'.
+	 */
+	i = quan(dln, table, size);
+	if (d < 0)			/* take 1's complement of i */
+		return ((size << 1) + 1 - i);
+	else if (i == 0)		/* take 1's complement of 0 */
+		return ((size << 1) + 1); /* new in 1988 */
+	else
+		return (i);
+}
+/*
+ * reconstruct()
+ *
+ * Returns reconstructed difference signal 'dq' obtained from
+ * codeword 'i' and quantization step size scale factor 'y'.
+ * Multiplication is performed in log base 2 domain as addition.
+ */
+int
+reconstruct(
+	int		sign,	/* 0 for non-negative value */
+	int		dqln,	/* G.72x codeword */
+	int		y)	/* Step size multiplier */
+{
+	short		dql;	/* Log of 'dq' magnitude */
+	short		dex;	/* Integer part of log */
+	short		dqt;
+	short		dq;	/* Reconstructed difference signal sample */
+
+	dql = dqln + (y >> 2);	/* ADDA */
+
+	if (dql < 0) {
+		return ((sign) ? -0x8000 : 0);
+	} else {		/* ANTILOG */
+		dex = (dql >> 7) & 15;
+		dqt = 128 + (dql & 127);
+		dq = (dqt << 7) >> (14 - dex);
+		return ((sign) ? (dq - 0x8000) : dq);
+	}
+}
+
+
+/*
+ * update()
+ *
+ * updates the state variables for each output code
+ */
+void
+update(
+	int		code_size,	/* distinguish 723_40 with others */
+	int		y,		/* quantizer step size */
+	int		wi,		/* scale factor multiplier */
+	int		fi,		/* for long/short term energies */
+	int		dq,		/* quantized prediction difference */
+	int		sr,		/* reconstructed signal */
+	int		dqsez,		/* difference from 2-pole predictor */
+	struct g72x_state *state_ptr)	/* coder state pointer */
+{
+	int		cnt;
+	short		mag, exp;	/* Adaptive predictor, FLOAT A */
+	short		a2p = 0;	/* LIMC */
+	short		a1ul;		/* UPA1 */
+	short		pks1;		/* UPA2 */
+	short		fa1;
+	char		tr;		/* tone/transition detector */
+	short		ylint, thr2, dqthr;
+	short  		ylfrac, thr1;
+	short		pk0;
+
+	pk0 = (dqsez < 0) ? 1 : 0;	/* needed in updating predictor poles */
+
+	mag = dq & 0x7FFF;		/* prediction difference magnitude */
+	/* TRANS */
+	ylint = state_ptr->yl >> 15;	/* exponent part of yl */
+	ylfrac = (state_ptr->yl >> 10) & 0x1F;	/* fractional part of yl */
+	thr1 = (32 + ylfrac) << ylint;		/* threshold */
+	thr2 = (ylint > 9) ? 31 << 10 : thr1;	/* limit thr2 to 31 << 10 */
+	dqthr = (thr2 + (thr2 >> 1)) >> 1;	/* dqthr = 0.75 * thr2 */
+	if (state_ptr->td == 0)		/* signal supposed voice */
+		tr = 0;
+	else if (mag <= dqthr)		/* supposed data, but small mag */
+		tr = 0;			/* treated as voice */
+	else				/* signal is data (modem) */
+		tr = 1;
+
+	/*
+	 * Quantizer scale factor adaptation.
+	 */
+
+	/* FUNCTW & FILTD & DELAY */
+	/* update non-steady state step size multiplier */
+	state_ptr->yu = y + ((wi - y) >> 5);
+
+	/* LIMB */
+	if (state_ptr->yu < 544)	/* 544 <= yu <= 5120 */
+		state_ptr->yu = 544;
+	else if (state_ptr->yu > 5120)
+		state_ptr->yu = 5120;
+
+	/* FILTE & DELAY */
+	/* update steady state step size multiplier */
+	state_ptr->yl += state_ptr->yu + ((-state_ptr->yl) >> 6);
+
+	/*
+	 * Adaptive predictor coefficients.
+	 */
+	if (tr == 1) {			/* reset a's and b's for modem signal */
+		state_ptr->a[0] = 0;
+		state_ptr->a[1] = 0;
+		state_ptr->b[0] = 0;
+		state_ptr->b[1] = 0;
+		state_ptr->b[2] = 0;
+		state_ptr->b[3] = 0;
+		state_ptr->b[4] = 0;
+		state_ptr->b[5] = 0;
+	} else {			/* update a's and b's */
+		pks1 = pk0 ^ state_ptr->pk[0];		/* UPA2 */
+
+		/* update predictor pole a[1] */
+		a2p = state_ptr->a[1] - (state_ptr->a[1] >> 7);
+		if (dqsez != 0) {
+			fa1 = (pks1) ? state_ptr->a[0] : -state_ptr->a[0];
+			if (fa1 < -8191)	/* a2p = function of fa1 */
+				a2p -= 0x100;
+			else if (fa1 > 8191)
+				a2p += 0xFF;
+			else
+				a2p += fa1 >> 5;
+
+			if (pk0 ^ state_ptr->pk[1])
+				/* LIMC */
+				if (a2p <= -12160)
+					a2p = -12288;
+				else if (a2p >= 12416)
+					a2p = 12288;
+				else
+					a2p -= 0x80;
+			else if (a2p <= -12416)
+				a2p = -12288;
+			else if (a2p >= 12160)
+				a2p = 12288;
+			else
+				a2p += 0x80;
+		}
+
+		/* TRIGB & DELAY */
+		state_ptr->a[1] = a2p;
+
+		/* UPA1 */
+		/* update predictor pole a[0] */
+		state_ptr->a[0] -= state_ptr->a[0] >> 8;
+		if (dqsez != 0) {
+			if (pks1 == 0)
+				state_ptr->a[0] += 192;
+			else
+				state_ptr->a[0] -= 192;
+		}
+
+		/* LIMD */
+		a1ul = 15360 - a2p;
+		if (state_ptr->a[0] < -a1ul)
+			state_ptr->a[0] = -a1ul;
+		else if (state_ptr->a[0] > a1ul)
+			state_ptr->a[0] = a1ul;
+
+		/* UPB : update predictor zeros b[6] */
+		for (cnt = 0; cnt < 6; cnt++) {
+			if (code_size == 5)		/* for 40Kbps G.723 */
+				state_ptr->b[cnt] -= state_ptr->b[cnt] >> 9;
+			else			/* for G.721 and 24Kbps G.723 */
+				state_ptr->b[cnt] -= state_ptr->b[cnt] >> 8;
+			if (dq & 0x7FFF) {			/* XOR */
+				if ((dq ^ state_ptr->dq[cnt]) >= 0)
+					state_ptr->b[cnt] += 128;
+				else
+					state_ptr->b[cnt] -= 128;
+			}
+		}
+	}
+
+	for (cnt = 5; cnt > 0; cnt--)
+		state_ptr->dq[cnt] = state_ptr->dq[cnt-1];
+	/* FLOAT A : convert dq[0] to 4-bit exp, 6-bit mantissa f.p. */
+	if (mag == 0) {
+		state_ptr->dq[0] = (dq >= 0) ? 0x20 : 0xFC20;
+	} else {
+		exp = quan(mag, power2, 15);
+		state_ptr->dq[0] = (dq >= 0) ?
+		    (exp << 6) + ((mag << 6) >> exp) :
+		    (exp << 6) + ((mag << 6) >> exp) - 0x400;
+	}
+
+	state_ptr->sr[1] = state_ptr->sr[0];
+	/* FLOAT B : convert sr to 4-bit exp., 6-bit mantissa f.p. */
+	if (sr == 0) {
+		state_ptr->sr[0] = 0x20;
+	} else if (sr > 0) {
+		exp = quan(sr, power2, 15);
+		state_ptr->sr[0] = (exp << 6) + ((sr << 6) >> exp);
+	} else if (sr > -32768) {
+		mag = -sr;
+		exp = quan(mag, power2, 15);
+		state_ptr->sr[0] =  (exp << 6) + ((mag << 6) >> exp) - 0x400;
+	} else
+		state_ptr->sr[0] = 0xFC20;
+
+	/* DELAY A */
+	state_ptr->pk[1] = state_ptr->pk[0];
+	state_ptr->pk[0] = pk0;
+
+	/* TONE */
+	if (tr == 1)		/* this sample has been treated as data */
+		state_ptr->td = 0;	/* next one will be treated as voice */
+	else if (a2p < -11776)	/* small sample-to-sample correlation */
+		state_ptr->td = 1;	/* signal may be data */
+	else				/* signal is voice */
+		state_ptr->td = 0;
+
+	/*
+	 * Adaptation speed control.
+	 */
+	state_ptr->dms += (fi - state_ptr->dms) >> 5;		/* FILTA */
+	state_ptr->dml += (((fi << 2) - state_ptr->dml) >> 7);	/* FILTB */
+
+	if (tr == 1)
+		state_ptr->ap = 256;
+	else if (y < 1536)					/* SUBTC */
+		state_ptr->ap += (0x200 - state_ptr->ap) >> 4;
+	else if (state_ptr->td == 1)
+		state_ptr->ap += (0x200 - state_ptr->ap) >> 4;
+	else if (abs((state_ptr->dms << 2) - state_ptr->dml) >=
+	    (state_ptr->dml >> 3))
+		state_ptr->ap += (0x200 - state_ptr->ap) >> 4;
+	else
+		state_ptr->ap += (-state_ptr->ap) >> 4;
+}
+
+/*
+ * tandem_adjust(sr, se, y, i, sign)
+ *
+ * At the end of ADPCM decoding, it simulates an encoder which may be receiving
+ * the output of this decoder as a tandem process. If the output of the
+ * simulated encoder differs from the input to this decoder, the decoder output
+ * is adjusted by one level of A-law or u-law codes.
+ *
+ * Input:
+ *	sr	decoder output linear PCM sample,
+ *	se	predictor estimate sample,
+ *	y	quantizer step size,
+ *	i	decoder input code,
+ *	sign	sign bit of code i
+ *
+ * Return:
+ *	adjusted A-law or u-law compressed sample.
+ */
+int
+tandem_adjust_alaw(
+	int		sr,	/* decoder output linear PCM sample */
+	int		se,	/* predictor estimate sample */
+	int		y,	/* quantizer step size */
+	int		i,	/* decoder input code */
+	int		sign,
+	short		*qtab)
+{
+	unsigned char	sp;	/* A-law compressed 8-bit code */
+	short		dx;	/* prediction error */
+	char		id;	/* quantized prediction error */
+	int		sd;	/* adjusted A-law decoded sample value */
+	int		im;	/* biased magnitude of i */
+	int		imx;	/* biased magnitude of id */
+
+	if (sr <= -32768)
+		sr = -1;
+	sp = linear2alaw((sr >> 1) << 3);	/* short to A-law compression */
+	dx = (alaw2linear(sp) >> 2) - se;	/* 16-bit prediction error */
+	id = quantize(dx, y, qtab, sign - 1);
+
+	if (id == i) {			/* no adjustment on sp */
+		return (sp);
+	} else {			/* sp adjustment needed */
+		/* ADPCM codes : 8, 9, ... F, 0, 1, ... , 6, 7 */
+		im = i ^ sign;		/* 2's complement to biased unsigned */
+		imx = id ^ sign;
+
+		if (imx > im) {		/* sp adjusted to next lower value */
+			if (sp & 0x80) {
+				sd = (sp == 0xD5) ? 0x55 :
+				    ((sp ^ 0x55) - 1) ^ 0x55;
+			} else {
+				sd = (sp == 0x2A) ? 0x2A :
+				    ((sp ^ 0x55) + 1) ^ 0x55;
+			}
+		} else {		/* sp adjusted to next higher value */
+			if (sp & 0x80)
+				sd = (sp == 0xAA) ? 0xAA :
+				    ((sp ^ 0x55) + 1) ^ 0x55;
+			else
+				sd = (sp == 0x55) ? 0xD5 :
+				    ((sp ^ 0x55) - 1) ^ 0x55;
+		}
+		return (sd);
+	}
+}
+
+int
+tandem_adjust_ulaw(
+	int		sr,	/* decoder output linear PCM sample */
+	int		se,	/* predictor estimate sample */
+	int		y,	/* quantizer step size */
+	int		i,	/* decoder input code */
+	int		sign,
+	short		*qtab)
+{
+	unsigned char	sp;	/* u-law compressed 8-bit code */
+	short		dx;	/* prediction error */
+	char		id;	/* quantized prediction error */
+	int		sd;	/* adjusted u-law decoded sample value */
+	int		im;	/* biased magnitude of i */
+	int		imx;	/* biased magnitude of id */
+
+	if (sr <= -32768)
+		sr = 0;
+	sp = linear2ulaw(sr << 2);	/* short to u-law compression */
+	dx = (ulaw2linear(sp) >> 2) - se;	/* 16-bit prediction error */
+	id = quantize(dx, y, qtab, sign - 1);
+	if (id == i) {
+		return (sp);
+	} else {
+		/* ADPCM codes : 8, 9, ... F, 0, 1, ... , 6, 7 */
+		im = i ^ sign;		/* 2's complement to biased unsigned */
+		imx = id ^ sign;
+		if (imx > im) {		/* sp adjusted to next lower value */
+			if (sp & 0x80)
+				sd = (sp == 0xFF) ? 0x7E : sp + 1;
+			else
+				sd = (sp == 0) ? 0 : sp - 1;
+
+		} else {		/* sp adjusted to next higher value */
+			if (sp & 0x80)
+				sd = (sp == 0x80) ? 0x80 : sp - 1;
+			else
+				sd = (sp == 0x7F) ? 0xFE : sp + 1;
+		}
+		return (sd);
+	}
+}
diff --git a/src/ccitt-adpcm/g72x.h b/src/ccitt-adpcm/g72x.h
new file mode 100644
index 0000000..3426176
--- /dev/null
+++ b/src/ccitt-adpcm/g72x.h
@@ -0,0 +1,148 @@
+/*
+ * This source code is a product of Sun Microsystems, Inc. and is provided
+ * for unrestricted use.  Users may copy or modify this source code without
+ * charge.
+ *
+ * SUN SOURCE CODE IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING
+ * THE WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
+ *
+ * Sun source code is provided with no support and without any obligation on
+ * the part of Sun Microsystems, Inc. to assist in its use, correction,
+ * modification or enhancement.
+ *
+ * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
+ * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY THIS SOFTWARE
+ * OR ANY PART THEREOF.
+ *
+ * In no event will Sun Microsystems, Inc. be liable for any lost revenue
+ * or profits or other special, indirect and consequential damages, even if
+ * Sun has been advised of the possibility of such damages.
+ *
+ * Sun Microsystems, Inc.
+ * 2550 Garcia Avenue
+ * Mountain View, California  94043
+ */
+
+/*
+ * g72x.h
+ *
+ * Header file for CCITT conversion routines.
+ *
+ */
+#ifndef _G72X_H
+#define	_G72X_H
+
+#define	AUDIO_ENCODING_ULAW	(1)	/* ISDN u-law */
+#define	AUDIO_ENCODING_ALAW	(2)	/* ISDN A-law */
+#define	AUDIO_ENCODING_LINEAR	(3)	/* PCM 2's-complement (0-center) */
+
+/*
+ * The following is the definition of the state structure
+ * used by the G.721/G.723 encoder and decoder to preserve their internal
+ * state between successive calls.  The meanings of the majority
+ * of the state structure fields are explained in detail in the
+ * CCITT Recommendation G.721.  The field names are essentially indentical
+ * to variable names in the bit level description of the coding algorithm
+ * included in this Recommendation.
+ */
+struct g72x_state {
+	long yl;	/* Locked or steady state step size multiplier. */
+	short yu;	/* Unlocked or non-steady state step size multiplier. */
+	short dms;	/* Short term energy estimate. */
+	short dml;	/* Long term energy estimate. */
+	short ap;	/* Linear weighting coefficient of 'yl' and 'yu'. */
+
+	short a[2];	/* Coefficients of pole portion of prediction filter. */
+	short b[6];	/* Coefficients of zero portion of prediction filter. */
+	short pk[2];	/*
+			 * Signs of previous two samples of a partially
+			 * reconstructed signal.
+			 */
+	short dq[6];	/*
+			 * Previous 6 samples of the quantized difference
+			 * signal represented in an internal floating point
+			 * format.
+			 */
+	short sr[2];	/*
+			 * Previous 2 samples of the quantized difference
+			 * signal represented in an internal floating point
+			 * format.
+			 */
+	char td;	/* delayed tone detect, new in 1988 version */
+};
+
+/* External function definitions. */
+
+extern void g72x_init_state(struct g72x_state *);
+extern int predictor_zero(struct g72x_state *state_ptr);
+extern int predictor_pole(struct g72x_state *state_ptr);
+extern int step_size(struct g72x_state *state_ptr);
+
+extern int quantize(
+		int d,
+		int y,
+		short *table,
+		int size);
+extern int reconstruct(
+		int sign,
+		int dqln,
+		int y);
+extern void update(
+		int code_size,
+		int y,
+		int wi,
+		int fi,
+		int dq,
+		int sr,
+		int dqsez,
+		struct g72x_state *state_ptr);
+
+extern int tandem_adjust_alaw(
+		int sr,
+		int se,
+		int y,
+		int i,
+		int sign,
+		short *qtab);
+extern int tandem_adjust_ulaw(
+		int sr,
+		int se,
+		int y,
+		int i,
+		int sign,
+		short *qtab);
+
+extern int g721_encoder(
+		int sample,
+		int in_coding,
+		struct g72x_state *state_ptr);
+extern int g721_decoder(
+		int code,
+		int out_coding,
+		struct g72x_state *state_ptr);
+extern int g723_24_encoder(
+		int sample,
+		int in_coding,
+		struct g72x_state *state_ptr);
+extern int g723_24_decoder(
+		int code,
+		int out_coding,
+		struct g72x_state *state_ptr);
+extern int g723_40_encoder(
+		int sample,
+		int in_coding,
+		struct g72x_state *state_ptr);
+extern int g723_40_decoder(
+		int code,
+		int out_coding,
+		struct g72x_state *state_ptr);
+
+extern unsigned char linear2alaw(int pcm_val);
+extern int alaw2linear(unsigned char a_val);
+extern unsigned char linear2ulaw(int pcm_val);
+extern int ulaw2linear(unsigned char u_val);
+extern unsigned char alaw2ulaw(unsigned char aval);
+extern unsigned char ulaw2alaw(unsigned char uval);
+
+#endif /* !_G72X_H */