1/*	$OpenBSD: mulaw.c,v 1.18 2015/06/25 06:43:46 ratchov Exp $ */
2/*	$NetBSD: mulaw.c,v 1.15 2001/01/18 20:28:20 jdolecek Exp $	*/
3
4/*
5 * Copyright (c) 1991-1993 Regents of the University of California.
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 * 3. All advertising materials mentioning features or use of this software
17 *    must display the following acknowledgement:
18 *	This product includes software developed by the Computer Systems
19 *	Engineering Group at Lawrence Berkeley Laboratory.
20 * 4. Neither the name of the University nor of the Laboratory may be used
21 *    to endorse or promote products derived from this software without
22 *    specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
35 *
36 */
37
38#include <sys/types.h>
39#include <dev/mulaw.h>
40
41/*
42 * This table converts a (8 bit) mu-law value two a 16 bit value.
43 * The 16 bits are represented as an array of two bytes for easier access
44 * to the individual bytes.
45 */
46static const u_char mulawtolin16[256][2] = {
47	{0x02,0x84}, {0x06,0x84}, {0x0a,0x84}, {0x0e,0x84},
48	{0x12,0x84}, {0x16,0x84}, {0x1a,0x84}, {0x1e,0x84},
49	{0x22,0x84}, {0x26,0x84}, {0x2a,0x84}, {0x2e,0x84},
50	{0x32,0x84}, {0x36,0x84}, {0x3a,0x84}, {0x3e,0x84},
51	{0x41,0x84}, {0x43,0x84}, {0x45,0x84}, {0x47,0x84},
52	{0x49,0x84}, {0x4b,0x84}, {0x4d,0x84}, {0x4f,0x84},
53	{0x51,0x84}, {0x53,0x84}, {0x55,0x84}, {0x57,0x84},
54	{0x59,0x84}, {0x5b,0x84}, {0x5d,0x84}, {0x5f,0x84},
55	{0x61,0x04}, {0x62,0x04}, {0x63,0x04}, {0x64,0x04},
56	{0x65,0x04}, {0x66,0x04}, {0x67,0x04}, {0x68,0x04},
57	{0x69,0x04}, {0x6a,0x04}, {0x6b,0x04}, {0x6c,0x04},
58	{0x6d,0x04}, {0x6e,0x04}, {0x6f,0x04}, {0x70,0x04},
59	{0x70,0xc4}, {0x71,0x44}, {0x71,0xc4}, {0x72,0x44},
60	{0x72,0xc4}, {0x73,0x44}, {0x73,0xc4}, {0x74,0x44},
61	{0x74,0xc4}, {0x75,0x44}, {0x75,0xc4}, {0x76,0x44},
62	{0x76,0xc4}, {0x77,0x44}, {0x77,0xc4}, {0x78,0x44},
63	{0x78,0xa4}, {0x78,0xe4}, {0x79,0x24}, {0x79,0x64},
64	{0x79,0xa4}, {0x79,0xe4}, {0x7a,0x24}, {0x7a,0x64},
65	{0x7a,0xa4}, {0x7a,0xe4}, {0x7b,0x24}, {0x7b,0x64},
66	{0x7b,0xa4}, {0x7b,0xe4}, {0x7c,0x24}, {0x7c,0x64},
67	{0x7c,0x94}, {0x7c,0xb4}, {0x7c,0xd4}, {0x7c,0xf4},
68	{0x7d,0x14}, {0x7d,0x34}, {0x7d,0x54}, {0x7d,0x74},
69	{0x7d,0x94}, {0x7d,0xb4}, {0x7d,0xd4}, {0x7d,0xf4},
70	{0x7e,0x14}, {0x7e,0x34}, {0x7e,0x54}, {0x7e,0x74},
71	{0x7e,0x8c}, {0x7e,0x9c}, {0x7e,0xac}, {0x7e,0xbc},
72	{0x7e,0xcc}, {0x7e,0xdc}, {0x7e,0xec}, {0x7e,0xfc},
73	{0x7f,0x0c}, {0x7f,0x1c}, {0x7f,0x2c}, {0x7f,0x3c},
74	{0x7f,0x4c}, {0x7f,0x5c}, {0x7f,0x6c}, {0x7f,0x7c},
75	{0x7f,0x88}, {0x7f,0x90}, {0x7f,0x98}, {0x7f,0xa0},
76	{0x7f,0xa8}, {0x7f,0xb0}, {0x7f,0xb8}, {0x7f,0xc0},
77	{0x7f,0xc8}, {0x7f,0xd0}, {0x7f,0xd8}, {0x7f,0xe0},
78	{0x7f,0xe8}, {0x7f,0xf0}, {0x7f,0xf8}, {0x80,0x00},
79	{0xfd,0x7c}, {0xf9,0x7c}, {0xf5,0x7c}, {0xf1,0x7c},
80	{0xed,0x7c}, {0xe9,0x7c}, {0xe5,0x7c}, {0xe1,0x7c},
81	{0xdd,0x7c}, {0xd9,0x7c}, {0xd5,0x7c}, {0xd1,0x7c},
82	{0xcd,0x7c}, {0xc9,0x7c}, {0xc5,0x7c}, {0xc1,0x7c},
83	{0xbe,0x7c}, {0xbc,0x7c}, {0xba,0x7c}, {0xb8,0x7c},
84	{0xb6,0x7c}, {0xb4,0x7c}, {0xb2,0x7c}, {0xb0,0x7c},
85	{0xae,0x7c}, {0xac,0x7c}, {0xaa,0x7c}, {0xa8,0x7c},
86	{0xa6,0x7c}, {0xa4,0x7c}, {0xa2,0x7c}, {0xa0,0x7c},
87	{0x9e,0xfc}, {0x9d,0xfc}, {0x9c,0xfc}, {0x9b,0xfc},
88	{0x9a,0xfc}, {0x99,0xfc}, {0x98,0xfc}, {0x97,0xfc},
89	{0x96,0xfc}, {0x95,0xfc}, {0x94,0xfc}, {0x93,0xfc},
90	{0x92,0xfc}, {0x91,0xfc}, {0x90,0xfc}, {0x8f,0xfc},
91	{0x8f,0x3c}, {0x8e,0xbc}, {0x8e,0x3c}, {0x8d,0xbc},
92	{0x8d,0x3c}, {0x8c,0xbc}, {0x8c,0x3c}, {0x8b,0xbc},
93	{0x8b,0x3c}, {0x8a,0xbc}, {0x8a,0x3c}, {0x89,0xbc},
94	{0x89,0x3c}, {0x88,0xbc}, {0x88,0x3c}, {0x87,0xbc},
95	{0x87,0x5c}, {0x87,0x1c}, {0x86,0xdc}, {0x86,0x9c},
96	{0x86,0x5c}, {0x86,0x1c}, {0x85,0xdc}, {0x85,0x9c},
97	{0x85,0x5c}, {0x85,0x1c}, {0x84,0xdc}, {0x84,0x9c},
98	{0x84,0x5c}, {0x84,0x1c}, {0x83,0xdc}, {0x83,0x9c},
99	{0x83,0x6c}, {0x83,0x4c}, {0x83,0x2c}, {0x83,0x0c},
100	{0x82,0xec}, {0x82,0xcc}, {0x82,0xac}, {0x82,0x8c},
101	{0x82,0x6c}, {0x82,0x4c}, {0x82,0x2c}, {0x82,0x0c},
102	{0x81,0xec}, {0x81,0xcc}, {0x81,0xac}, {0x81,0x8c},
103	{0x81,0x74}, {0x81,0x64}, {0x81,0x54}, {0x81,0x44},
104	{0x81,0x34}, {0x81,0x24}, {0x81,0x14}, {0x81,0x04},
105	{0x80,0xf4}, {0x80,0xe4}, {0x80,0xd4}, {0x80,0xc4},
106	{0x80,0xb4}, {0x80,0xa4}, {0x80,0x94}, {0x80,0x84},
107	{0x80,0x78}, {0x80,0x70}, {0x80,0x68}, {0x80,0x60},
108	{0x80,0x58}, {0x80,0x50}, {0x80,0x48}, {0x80,0x40},
109	{0x80,0x38}, {0x80,0x30}, {0x80,0x28}, {0x80,0x20},
110	{0x80,0x18}, {0x80,0x10}, {0x80,0x08}, {0x80,0x00},
111};
112
113static const u_char lintomulaw[256] = {
114	0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x01, 0x01,
115	0x01, 0x02, 0x02, 0x02, 0x02, 0x03, 0x03, 0x03,
116	0x03, 0x04, 0x04, 0x04, 0x04, 0x05, 0x05, 0x05,
117	0x05, 0x06, 0x06, 0x06, 0x06, 0x07, 0x07, 0x07,
118	0x07, 0x08, 0x08, 0x08, 0x08, 0x09, 0x09, 0x09,
119	0x09, 0x0a, 0x0a, 0x0a, 0x0a, 0x0b, 0x0b, 0x0b,
120	0x0b, 0x0c, 0x0c, 0x0c, 0x0c, 0x0d, 0x0d, 0x0d,
121	0x0d, 0x0e, 0x0e, 0x0e, 0x0e, 0x0f, 0x0f, 0x0f,
122	0x0f, 0x10, 0x10, 0x11, 0x11, 0x12, 0x12, 0x13,
123	0x13, 0x14, 0x14, 0x15, 0x15, 0x16, 0x16, 0x17,
124	0x17, 0x18, 0x18, 0x19, 0x19, 0x1a, 0x1a, 0x1b,
125	0x1b, 0x1c, 0x1c, 0x1d, 0x1d, 0x1e, 0x1e, 0x1f,
126	0x1f, 0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26,
127	0x27, 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e,
128	0x2f, 0x30, 0x32, 0x34, 0x36, 0x38, 0x3a, 0x3c,
129	0x3e, 0x41, 0x45, 0x49, 0x4d, 0x53, 0x5b, 0x67,
130	0xff, 0xe7, 0xdb, 0xd3, 0xcd, 0xc9, 0xc5, 0xc1,
131	0xbe, 0xbc, 0xba, 0xb8, 0xb6, 0xb4, 0xb2, 0xb0,
132	0xaf, 0xae, 0xad, 0xac, 0xab, 0xaa, 0xa9, 0xa8,
133	0xa7, 0xa6, 0xa5, 0xa4, 0xa3, 0xa2, 0xa1, 0xa0,
134	0x9f, 0x9f, 0x9e, 0x9e, 0x9d, 0x9d, 0x9c, 0x9c,
135	0x9b, 0x9b, 0x9a, 0x9a, 0x99, 0x99, 0x98, 0x98,
136	0x97, 0x97, 0x96, 0x96, 0x95, 0x95, 0x94, 0x94,
137	0x93, 0x93, 0x92, 0x92, 0x91, 0x91, 0x90, 0x90,
138	0x8f, 0x8f, 0x8f, 0x8f, 0x8e, 0x8e, 0x8e, 0x8e,
139	0x8d, 0x8d, 0x8d, 0x8d, 0x8c, 0x8c, 0x8c, 0x8c,
140	0x8b, 0x8b, 0x8b, 0x8b, 0x8a, 0x8a, 0x8a, 0x8a,
141	0x89, 0x89, 0x89, 0x89, 0x88, 0x88, 0x88, 0x88,
142	0x87, 0x87, 0x87, 0x87, 0x86, 0x86, 0x86, 0x86,
143	0x85, 0x85, 0x85, 0x85, 0x84, 0x84, 0x84, 0x84,
144	0x83, 0x83, 0x83, 0x83, 0x82, 0x82, 0x82, 0x82,
145	0x81, 0x81, 0x81, 0x81, 0x80, 0x80, 0x80, 0x80,
146};
147
148void
149mulaw_to_slinear8(u_char *p, int cc)
150{
151	/* Use the 16 bit table for 8 bits too. */
152	while (--cc >= 0) {
153		*p = mulawtolin16[*p][0] ^ 0x80;
154		++p;
155	}
156}
157
158void
159slinear8_to_mulaw(u_char *p, int cc)
160{
161	while (--cc >= 0) {
162		*p = lintomulaw[*p ^ 0x80];
163		++p;
164	}
165}
166
167void
168mulaw24_to_slinear24(u_char *p, int cc)
169{
170	int s, *q = (int *)p;
171
172	while ((cc -= 4) >= 0) {
173		s = (*q >> 16) & 0xff;
174		*q = (int)((signed char)mulawtolin16[s][0] ^ 0x80) << 16 |
175		    (u_int)mulawtolin16[s][1] << 8;
176		q++;
177	}
178}
179
180void
181slinear24_to_mulaw24(u_char *p, int cc)
182{
183	u_int *q = (u_int *)p;
184
185	while ((cc -= 4) >= 0) {
186		*q = lintomulaw[((*q >> 16) & 0xff) ^ 0x80] << 16;
187		q++;
188	}
189}
190