Alexandre Lision | 7c6f4a6 | 2013-09-05 13:27:01 -0400 | [diff] [blame] | 1 | /* |
| 2 | ** Copyright (C) 1999-2011 Erik de Castro Lopo <erikd@mega-nerd.com> |
| 3 | ** |
| 4 | ** This program is free software; you can redistribute it and/or modify |
| 5 | ** it under the terms of the GNU General Public License as published by |
| 6 | ** the Free Software Foundation; either version 2 of the License, or |
| 7 | ** (at your option) any later version. |
| 8 | ** |
| 9 | ** This program is distributed in the hope that it will be useful, |
| 10 | ** but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | ** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 12 | ** GNU General Public License for more details. |
| 13 | ** |
| 14 | ** You should have received a copy of the GNU General Public License |
| 15 | ** along with this program; if not, write to the Free Software |
| 16 | ** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
| 17 | */ |
| 18 | |
| 19 | #include "sfconfig.h" |
| 20 | |
| 21 | #include <stdio.h> |
| 22 | #include <stdlib.h> |
| 23 | #include <string.h> |
| 24 | |
| 25 | #if HAVE_UNISTD_H |
| 26 | #include <unistd.h> |
| 27 | #endif |
| 28 | |
| 29 | #include <sndfile.h> |
| 30 | |
| 31 | #include "utils.h" |
| 32 | |
| 33 | #define BUFFER_SIZE (65536) |
| 34 | |
| 35 | static unsigned char alaw_encode (int sample) ; |
| 36 | static int alaw_decode (unsigned int alawbyte) ; |
| 37 | |
| 38 | static short short_buffer [BUFFER_SIZE] ; |
| 39 | static unsigned char alaw_buffer [BUFFER_SIZE] ; |
| 40 | |
| 41 | int |
| 42 | main (void) |
| 43 | { SNDFILE *file ; |
| 44 | SF_INFO sfinfo ; |
| 45 | const char *filename ; |
| 46 | int k ; |
| 47 | |
| 48 | print_test_name ("alaw_test", "encoder") ; |
| 49 | |
| 50 | filename = "test.raw" ; |
| 51 | |
| 52 | sf_info_setup (&sfinfo, SF_FORMAT_RAW | SF_FORMAT_ALAW, 44100, 1) ; |
| 53 | |
| 54 | if ((file = sf_open (filename, SFM_WRITE, &sfinfo)) == NULL) |
| 55 | { printf ("sf_open_write failed with error : ") ; |
| 56 | fflush (stdout) ; |
| 57 | puts (sf_strerror (NULL)) ; |
| 58 | exit (1) ; |
| 59 | } ; |
| 60 | |
| 61 | /* Generate a file containing all possible 16 bit sample values |
| 62 | ** and write it to disk as alaw encoded.frames. |
| 63 | */ |
| 64 | |
| 65 | for (k = 0 ; k < 0x10000 ; k++) |
| 66 | short_buffer [k] = k & 0xFFFF ; |
| 67 | |
| 68 | sf_write_short (file, short_buffer, BUFFER_SIZE) ; |
| 69 | sf_close (file) ; |
| 70 | |
| 71 | /* Now open that file and compare the alaw encoded sample values |
| 72 | ** with what they should be. |
| 73 | */ |
| 74 | |
| 75 | if ((file = sf_open (filename, SFM_READ, &sfinfo)) == NULL) |
| 76 | { printf ("sf_open_write failed with error : ") ; |
| 77 | puts (sf_strerror (NULL)) ; |
| 78 | exit (1) ; |
| 79 | } ; |
| 80 | |
| 81 | check_log_buffer_or_die (file, __LINE__) ; |
| 82 | |
| 83 | if (sf_read_raw (file, alaw_buffer, BUFFER_SIZE) != BUFFER_SIZE) |
| 84 | { printf ("sf_read_raw : ") ; |
| 85 | puts (sf_strerror (file)) ; |
| 86 | exit (1) ; |
| 87 | } ; |
| 88 | |
| 89 | for (k = 0 ; k < 0x10000 ; k++) |
| 90 | if (alaw_encode (short_buffer [k]) != alaw_buffer [k]) |
| 91 | { printf ("Encoder error : sample #%d (0x%02X should be 0x%02X)\n", k, alaw_buffer [k], alaw_encode (short_buffer [k])) ; |
| 92 | exit (1) ; |
| 93 | } ; |
| 94 | |
| 95 | sf_close (file) ; |
| 96 | |
| 97 | puts ("ok") ; |
| 98 | |
| 99 | print_test_name ("alaw_test", "decoder") ; |
| 100 | /* Now generate a file containing all possible 8 bit encoded |
| 101 | ** sample values and write it to disk as alaw encoded.frames. |
| 102 | */ |
| 103 | |
| 104 | if (! (file = sf_open (filename, SFM_WRITE, &sfinfo))) |
| 105 | { printf ("sf_open_write failed with error : ") ; |
| 106 | puts (sf_strerror (NULL)) ; |
| 107 | exit (1) ; |
| 108 | } ; |
| 109 | |
| 110 | for (k = 0 ; k < 256 ; k++) |
| 111 | alaw_buffer [k] = k & 0xFF ; |
| 112 | |
| 113 | sf_write_raw (file, alaw_buffer, 256) ; |
| 114 | sf_close (file) ; |
| 115 | |
| 116 | /* Now open that file and compare the alaw decoded sample values |
| 117 | ** with what they should be. |
| 118 | */ |
| 119 | |
| 120 | if (! (file = sf_open (filename, SFM_READ, &sfinfo))) |
| 121 | { printf ("sf_open_write failed with error : ") ; |
| 122 | puts (sf_strerror (NULL)) ; |
| 123 | exit (1) ; |
| 124 | } ; |
| 125 | |
| 126 | check_log_buffer_or_die (file, __LINE__) ; |
| 127 | |
| 128 | if (sf_read_short (file, short_buffer, 256) != 256) |
| 129 | { printf ("sf_read_short : ") ; |
| 130 | puts (sf_strerror (file)) ; |
| 131 | exit (1) ; |
| 132 | } ; |
| 133 | |
| 134 | |
| 135 | for (k = 0 ; k < 256 ; k++) |
| 136 | if (short_buffer [k] != alaw_decode (alaw_buffer [k])) |
| 137 | { printf ("Decoder error : sample #%d (0x%02X should be 0x%02X)\n", k, short_buffer [k], alaw_decode (alaw_buffer [k])) ; |
| 138 | exit (1) ; |
| 139 | } ; |
| 140 | |
| 141 | sf_close (file) ; |
| 142 | |
| 143 | puts ("ok") ; |
| 144 | |
| 145 | unlink (filename) ; |
| 146 | |
| 147 | return 0 ; |
| 148 | } /* main */ |
| 149 | |
| 150 | |
| 151 | /*================================================================================= |
| 152 | ** The following routines came from the sox-12.15 (Sound eXcahcnge) distribution. |
| 153 | ** |
| 154 | ** This code is not compiled into libsndfile. It is only used to test the |
| 155 | ** libsndfile lookup tables for correctness. |
| 156 | ** |
| 157 | ** I have included the original authors comments. |
| 158 | */ |
| 159 | |
| 160 | /* |
| 161 | ** A-law routines by Graeme W. Gill. |
| 162 | ** Date: 93/5/7 |
| 163 | ** |
| 164 | ** References: |
| 165 | ** 1) CCITT Recommendation G.711 |
| 166 | ** |
| 167 | */ |
| 168 | |
| 169 | #define ACLIP 31744 |
| 170 | |
| 171 | static |
| 172 | unsigned char alaw_encode (int sample) |
| 173 | { static int exp_lut [128] = |
| 174 | { 1, 1, 2, 2, 3, 3, 3, 3, |
| 175 | 4, 4, 4, 4, 4, 4, 4, 4, |
| 176 | 5, 5, 5, 5, 5, 5, 5, 5, |
| 177 | 5, 5, 5, 5, 5, 5, 5, 5, |
| 178 | 6, 6, 6, 6, 6, 6, 6, 6, |
| 179 | 6, 6, 6, 6, 6, 6, 6, 6, |
| 180 | 6, 6, 6, 6, 6, 6, 6, 6, |
| 181 | 6, 6, 6, 6, 6, 6, 6, 6, |
| 182 | 7, 7, 7, 7, 7, 7, 7, 7, |
| 183 | 7, 7, 7, 7, 7, 7, 7, 7, |
| 184 | 7, 7, 7, 7, 7, 7, 7, 7, |
| 185 | 7, 7, 7, 7, 7, 7, 7, 7, |
| 186 | 7, 7, 7, 7, 7, 7, 7, 7, |
| 187 | 7, 7, 7, 7, 7, 7, 7, 7, |
| 188 | 7, 7, 7, 7, 7, 7, 7, 7, |
| 189 | 7, 7, 7, 7, 7, 7, 7, 7 |
| 190 | } ; |
| 191 | |
| 192 | int sign, exponent, mantissa ; |
| 193 | unsigned char Alawbyte ; |
| 194 | |
| 195 | /* Get the sample into sign-magnitude. */ |
| 196 | sign = ((~sample) >> 8) & 0x80 ; /* set aside the sign */ |
| 197 | if (sign == 0) |
| 198 | sample = -sample ; /* get magnitude */ |
| 199 | if (sample > ACLIP) |
| 200 | sample = ACLIP ; /* clip the magnitude */ |
| 201 | |
| 202 | /* Convert from 16 bit linear to ulaw. */ |
| 203 | if (sample >= 256) |
| 204 | { exponent = exp_lut [(sample >> 8) & 0x7F] ; |
| 205 | mantissa = ( sample >> ( exponent + 3 ) ) & 0x0F ; |
| 206 | Alawbyte = ((exponent << 4) | mantissa) ; |
| 207 | } |
| 208 | else |
| 209 | Alawbyte = (sample >> 4) ; |
| 210 | |
| 211 | Alawbyte ^= (sign ^ 0x55) ; |
| 212 | |
| 213 | return Alawbyte ; |
| 214 | } /* alaw_encode */ |
| 215 | |
| 216 | static |
| 217 | int alaw_decode (unsigned int Alawbyte) |
| 218 | { static int exp_lut [8] = { 0, 264, 528, 1056, 2112, 4224, 8448, 16896 } ; |
| 219 | int sign, exponent, mantissa, sample ; |
| 220 | |
| 221 | Alawbyte ^= 0x55 ; |
| 222 | sign = (Alawbyte & 0x80) ; |
| 223 | Alawbyte &= 0x7f ; /* get magnitude */ |
| 224 | if (Alawbyte >= 16) |
| 225 | { exponent = (Alawbyte >> 4 ) & 0x07 ; |
| 226 | mantissa = Alawbyte & 0x0F ; |
| 227 | sample = exp_lut [exponent] + (mantissa << ( exponent + 3 )) ; |
| 228 | } |
| 229 | else |
| 230 | sample = (Alawbyte << 4) + 8 ; |
| 231 | if (sign == 0) |
| 232 | sample = -sample ; |
| 233 | |
| 234 | return sample ; |
| 235 | } /* alaw_decode */ |
| 236 | |