alaw.c revision 1.2
1 /* $NetBSD: alaw.c,v 1.2 2019/05/08 13:40:17 isaki Exp $ */ 2 3 /* 4 * Copyright (C) 2018 Tetsuya Isaki. All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 20 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 21 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 22 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 23 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 */ 27 28 #include <sys/cdefs.h> 29 __KERNEL_RCSID(0, "$NetBSD: alaw.c,v 1.2 2019/05/08 13:40:17 isaki Exp $"); 30 31 #if defined(_KERNEL) 32 #include <sys/types.h> 33 #include <sys/systm.h> 34 #include <sys/device.h> 35 #include <dev/audio/audiovar.h> 36 #include <dev/audio/mulaw.h> 37 #endif 38 39 static const uint16_t alaw_to_slinear16[256] = { 40 0xea80, 0xeb80, 0xe880, 0xe980, 0xee80, 0xef80, 0xec80, 0xed80, 41 0xe280, 0xe380, 0xe080, 0xe180, 0xe680, 0xe780, 0xe480, 0xe580, 42 0xf540, 0xf5c0, 0xf440, 0xf4c0, 0xf740, 0xf7c0, 0xf640, 0xf6c0, 43 0xf140, 0xf1c0, 0xf040, 0xf0c0, 0xf340, 0xf3c0, 0xf240, 0xf2c0, 44 0xaa00, 0xae00, 0xa200, 0xa600, 0xba00, 0xbe00, 0xb200, 0xb600, 45 0x8a00, 0x8e00, 0x8200, 0x8600, 0x9a00, 0x9e00, 0x9200, 0x9600, 46 0xd500, 0xd700, 0xd100, 0xd300, 0xdd00, 0xdf00, 0xd900, 0xdb00, 47 0xc500, 0xc700, 0xc100, 0xc300, 0xcd00, 0xcf00, 0xc900, 0xcb00, 48 0xfea8, 0xfeb8, 0xfe88, 0xfe98, 0xfee8, 0xfef8, 0xfec8, 0xfed8, 49 0xfe28, 0xfe38, 0xfe08, 0xfe18, 0xfe68, 0xfe78, 0xfe48, 0xfe58, 50 0xffa8, 0xffb8, 0xff88, 0xff98, 0xffe8, 0xfff8, 0xffc8, 0xffd8, 51 0xff28, 0xff38, 0xff08, 0xff18, 0xff68, 0xff78, 0xff48, 0xff58, 52 0xfaa0, 0xfae0, 0xfa20, 0xfa60, 0xfba0, 0xfbe0, 0xfb20, 0xfb60, 53 0xf8a0, 0xf8e0, 0xf820, 0xf860, 0xf9a0, 0xf9e0, 0xf920, 0xf960, 54 0xfd50, 0xfd70, 0xfd10, 0xfd30, 0xfdd0, 0xfdf0, 0xfd90, 0xfdb0, 55 0xfc50, 0xfc70, 0xfc10, 0xfc30, 0xfcd0, 0xfcf0, 0xfc90, 0xfcb0, 56 0x1580, 0x1480, 0x1780, 0x1680, 0x1180, 0x1080, 0x1380, 0x1280, 57 0x1d80, 0x1c80, 0x1f80, 0x1e80, 0x1980, 0x1880, 0x1b80, 0x1a80, 58 0x0ac0, 0x0a40, 0x0bc0, 0x0b40, 0x08c0, 0x0840, 0x09c0, 0x0940, 59 0x0ec0, 0x0e40, 0x0fc0, 0x0f40, 0x0cc0, 0x0c40, 0x0dc0, 0x0d40, 60 0x5600, 0x5200, 0x5e00, 0x5a00, 0x4600, 0x4200, 0x4e00, 0x4a00, 61 0x7600, 0x7200, 0x7e00, 0x7a00, 0x6600, 0x6200, 0x6e00, 0x6a00, 62 0x2b00, 0x2900, 0x2f00, 0x2d00, 0x2300, 0x2100, 0x2700, 0x2500, 63 0x3b00, 0x3900, 0x3f00, 0x3d00, 0x3300, 0x3100, 0x3700, 0x3500, 64 0x0158, 0x0148, 0x0178, 0x0168, 0x0118, 0x0108, 0x0138, 0x0128, 65 0x01d8, 0x01c8, 0x01f8, 0x01e8, 0x0198, 0x0188, 0x01b8, 0x01a8, 66 0x0058, 0x0048, 0x0078, 0x0068, 0x0018, 0x0008, 0x0038, 0x0028, 67 0x00d8, 0x00c8, 0x00f8, 0x00e8, 0x0098, 0x0088, 0x00b8, 0x00a8, 68 0x0560, 0x0520, 0x05e0, 0x05a0, 0x0460, 0x0420, 0x04e0, 0x04a0, 69 0x0760, 0x0720, 0x07e0, 0x07a0, 0x0660, 0x0620, 0x06e0, 0x06a0, 70 0x02b0, 0x0290, 0x02f0, 0x02d0, 0x0230, 0x0210, 0x0270, 0x0250, 71 0x03b0, 0x0390, 0x03f0, 0x03d0, 0x0330, 0x0310, 0x0370, 0x0350, 72 }; 73 74 static const uint8_t slinear8_to_alaw[256] = { 75 0xd5, 0xc5, 0xf5, 0xfd, 0xe5, 0xe1, 0xed, 0xe9, 76 0x95, 0x97, 0x91, 0x93, 0x9d, 0x9f, 0x99, 0x9b, 77 0x85, 0x84, 0x87, 0x86, 0x81, 0x80, 0x83, 0x82, 78 0x8d, 0x8c, 0x8f, 0x8e, 0x89, 0x88, 0x8b, 0x8a, 79 0xb5, 0xb5, 0xb4, 0xb4, 0xb7, 0xb7, 0xb6, 0xb6, 80 0xb1, 0xb1, 0xb0, 0xb0, 0xb3, 0xb3, 0xb2, 0xb2, 81 0xbd, 0xbd, 0xbc, 0xbc, 0xbf, 0xbf, 0xbe, 0xbe, 82 0xb9, 0xb9, 0xb8, 0xb8, 0xbb, 0xbb, 0xba, 0xba, 83 0xa5, 0xa5, 0xa5, 0xa5, 0xa4, 0xa4, 0xa4, 0xa4, 84 0xa7, 0xa7, 0xa7, 0xa7, 0xa6, 0xa6, 0xa6, 0xa6, 85 0xa1, 0xa1, 0xa1, 0xa1, 0xa0, 0xa0, 0xa0, 0xa0, 86 0xa3, 0xa3, 0xa3, 0xa3, 0xa2, 0xa2, 0xa2, 0xa2, 87 0xad, 0xad, 0xad, 0xad, 0xac, 0xac, 0xac, 0xac, 88 0xaf, 0xaf, 0xaf, 0xaf, 0xae, 0xae, 0xae, 0xae, 89 0xa9, 0xa9, 0xa9, 0xa9, 0xa8, 0xa8, 0xa8, 0xa8, 90 0xab, 0xab, 0xab, 0xab, 0xaa, 0xaa, 0xaa, 0xaa, 91 0x2a, 0x2a, 0x2a, 0x2a, 0x2b, 0x2b, 0x2b, 0x2b, 92 0x28, 0x28, 0x28, 0x28, 0x29, 0x29, 0x29, 0x29, 93 0x2e, 0x2e, 0x2e, 0x2e, 0x2f, 0x2f, 0x2f, 0x2f, 94 0x2c, 0x2c, 0x2c, 0x2c, 0x2d, 0x2d, 0x2d, 0x2d, 95 0x22, 0x22, 0x22, 0x22, 0x23, 0x23, 0x23, 0x23, 96 0x20, 0x20, 0x20, 0x20, 0x21, 0x21, 0x21, 0x21, 97 0x26, 0x26, 0x26, 0x26, 0x27, 0x27, 0x27, 0x27, 98 0x24, 0x24, 0x24, 0x24, 0x25, 0x25, 0x25, 0x25, 99 0x3a, 0x3a, 0x3b, 0x3b, 0x38, 0x38, 0x39, 0x39, 100 0x3e, 0x3e, 0x3f, 0x3f, 0x3c, 0x3c, 0x3d, 0x3d, 101 0x32, 0x32, 0x33, 0x33, 0x30, 0x30, 0x31, 0x31, 102 0x36, 0x36, 0x37, 0x37, 0x34, 0x34, 0x35, 0x35, 103 0x0a, 0x0b, 0x08, 0x09, 0x0e, 0x0f, 0x0c, 0x0d, 104 0x02, 0x03, 0x00, 0x01, 0x06, 0x07, 0x04, 0x05, 105 0x1a, 0x18, 0x1e, 0x1c, 0x12, 0x10, 0x16, 0x14, 106 0x6a, 0x6e, 0x62, 0x66, 0x7a, 0x72, 0x4a, 0x5a, 107 }; 108 109 /* 110 * audio_alaw_to_internal: 111 * This filter performs conversion from A-law to internal format. 112 */ 113 void 114 audio_alaw_to_internal(audio_filter_arg_t *arg) 115 { 116 const uint8_t *s; 117 aint_t *d; 118 u_int sample_count; 119 u_int i; 120 121 DIAGNOSTIC_filter_arg(arg); 122 KASSERT(arg->srcfmt->encoding == AUDIO_ENCODING_ALAW); 123 KASSERT(arg->srcfmt->stride == 8); 124 KASSERT(arg->srcfmt->precision == 8); 125 KASSERT(audio_format2_is_internal(arg->dstfmt)); 126 KASSERT(arg->srcfmt->channels == arg->dstfmt->channels); 127 128 s = arg->src; 129 d = arg->dst; 130 sample_count = arg->count * arg->srcfmt->channels; 131 132 for (i = 0; i < sample_count; i++) { 133 aint_t val; 134 val = alaw_to_slinear16[*s++]; 135 val <<= AUDIO_INTERNAL_BITS - 16; 136 *d++ = val; 137 } 138 } 139 140 /* 141 * audio_internal_to_alaw: 142 * This filter performs conversion from internal format to A-law. 143 */ 144 void 145 audio_internal_to_alaw(audio_filter_arg_t *arg) 146 { 147 const aint_t *s; 148 uint8_t *d; 149 u_int sample_count; 150 u_int i; 151 152 DIAGNOSTIC_filter_arg(arg); 153 KASSERT(arg->dstfmt->encoding == AUDIO_ENCODING_ALAW); 154 KASSERT(arg->dstfmt->stride == 8); 155 KASSERT(arg->dstfmt->precision == 8); 156 KASSERT(audio_format2_is_internal(arg->srcfmt)); 157 KASSERT(arg->srcfmt->channels == arg->dstfmt->channels); 158 159 s = arg->src; 160 d = arg->dst; 161 sample_count = arg->count * arg->srcfmt->channels; 162 163 for (i = 0; i < sample_count; i++) { 164 uint8_t val; 165 val = (*s++) >> (AUDIO_INTERNAL_BITS - 8); 166 *d++ = slinear8_to_alaw[val]; 167 } 168 } 169
Indexes created Mon Sep 22 10:09:38 GMT 2025