src/avr.c

   1 /* AVR file format handler for SoX
   2  * Copyright (C) 1999 Jan Paul Schmidt <jps@fundament.org>
   3  *
   4  * This library is free software; you can redistribute it and/or modify it
   5  * under the terms of the GNU Lesser General Public License as published by
   6  * the Free Software Foundation; either version 2.1 of the License, or (at
   7  * your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful, but
  10  * WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser
  12  * General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public License
  15  * along with this library; if not, write to the Free Software Foundation,
  16  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
  17  */
  18
  19 #include "sox_i.h"
  20
  21 #include <stdio.h>
  22 #include <string.h>
  23
  24 #define AVR_MAGIC "2BIT"
  25
  26 /* Taken from the Audio File Formats FAQ */
  27
  28 typedef struct {
  29   char magic [5];      /* 2BIT */
  30   char name [8];       /* null-padded sample name */
  31   unsigned short mono; /* 0 = mono, 0xffff = stereo */
  32   unsigned short rez;  /* 8 = 8 bit, 16 = 16 bit */
  33   unsigned short sign; /* 0 = unsigned, 0xffff = signed */
  34   unsigned short loop; /* 0 = no loop, 0xffff = looping sample */
  35   unsigned short midi; /* 0xffff = no MIDI note assigned,
  36                           0xffXX = single key note assignment
  37                           0xLLHH = key split, low/hi note */
  38   uint32_t rate;       /* sample frequency in hertz */
  39   uint32_t size;       /* sample length in bytes or words (see rez) */
  40   uint32_t lbeg;       /* offset to start of loop in bytes or words.
  41                           set to zero if unused. */
  42   uint32_t lend;       /* offset to end of loop in bytes or words.
  43                           set to sample length if unused. */
  44   unsigned short res1; /* Reserved, MIDI keyboard split */
  45   unsigned short res2; /* Reserved, sample compression */
  46   unsigned short res3; /* Reserved */
  47   char ext[20];        /* Additional filename space, used
  48                           if (name[7] != 0) */
  49   char user[64];       /* User defined. Typically ASCII message. */
  50 } priv_t;
  51
  52
  53
  54 /*
  55  * Do anything required before you start reading samples.
  56  * Read file header.
  57  *      Find out sampling rate,
  58  *      size and encoding of samples,
  59  *      mono/stereo/quad.
  60  */
  61
  62
  63 static int startread(sox_format_t * ft)
  64 {
  65   priv_t * avr = (priv_t *)ft->priv;
  66   int rc;
  67
  68   lsx_reads(ft, avr->magic, (size_t)4);
  69
  70   if (strncmp (avr->magic, AVR_MAGIC, (size_t)4)) {
  71     lsx_fail_errno(ft,SOX_EHDR,"AVR: unknown header");
  72     return(SOX_EOF);
  73   }
  74
  75   lsx_readbuf(ft, avr->name, sizeof(avr->name));
  76
  77   lsx_readw (ft, &(avr->mono));
  78   if (avr->mono) {
  79     ft->signal.channels = 2;
  80   }
  81   else {
  82     ft->signal.channels = 1;
  83   }
  84
  85   lsx_readw (ft, &(avr->rez));
  86   if (avr->rez == 8) {
  87     ft->encoding.bits_per_sample = 8;
  88   }
  89   else if (avr->rez == 16) {
  90     ft->encoding.bits_per_sample = 16;
  91   }
  92   else {
  93     lsx_fail_errno(ft,SOX_EFMT,"AVR: unsupported sample resolution");
  94     return(SOX_EOF);
  95   }
  96
  97   lsx_readw (ft, &(avr->sign));
  98   if (avr->sign) {
  99     ft->encoding.encoding = SOX_ENCODING_SIGN2;
 100   }
 101   else {
 102     ft->encoding.encoding = SOX_ENCODING_UNSIGNED;
 103   }
 104
 105   lsx_readw (ft, &(avr->loop));
 106
 107   lsx_readw (ft, &(avr->midi));
 108
 109   lsx_readdw (ft, &(avr->rate));
 110   /*
 111    * No support for AVRs created by ST-Replay,
 112    * Replay Proffesional and PRO-Series 12.
 113    *
 114    * Just masking the upper byte out.
 115    */
 116   ft->signal.rate = (avr->rate & 0x00ffffff);
 117
 118   lsx_readdw (ft, &(avr->size));
 119
 120   lsx_readdw (ft, &(avr->lbeg));
 121
 122   lsx_readdw (ft, &(avr->lend));
 123
 124   lsx_readw (ft, &(avr->res1));
 125
 126   lsx_readw (ft, &(avr->res2));
 127
 128   lsx_readw (ft, &(avr->res3));
 129
 130   lsx_readbuf(ft, avr->ext, sizeof(avr->ext));
 131
 132   lsx_readbuf(ft, avr->user, sizeof(avr->user));
 133
 134   rc = lsx_rawstartread (ft);
 135   if (rc)
 136       return rc;
 137
 138   return(SOX_SUCCESS);
 139 }
 140
 141 static int startwrite(sox_format_t * ft)
 142 {
 143   priv_t * avr = (priv_t *)ft->priv;
 144   int rc;
 145
 146   if (!ft->seekable) {
 147     lsx_fail_errno(ft,SOX_EOF,"AVR: file is not seekable");
 148     return(SOX_EOF);
 149   }
 150
 151   rc = lsx_rawstartwrite (ft);
 152   if (rc)
 153       return rc;
 154
 155   /* magic */
 156   lsx_writes(ft, AVR_MAGIC);
 157
 158   /* name */
 159   lsx_writeb(ft, 0);
 160   lsx_writeb(ft, 0);
 161   lsx_writeb(ft, 0);
 162   lsx_writeb(ft, 0);
 163   lsx_writeb(ft, 0);
 164   lsx_writeb(ft, 0);
 165   lsx_writeb(ft, 0);
 166   lsx_writeb(ft, 0);
 167
 168   /* mono */
 169   if (ft->signal.channels == 1) {
 170     lsx_writew (ft, 0);
 171   }
 172   else if (ft->signal.channels == 2) {
 173     lsx_writew (ft, 0xffff);
 174   }
 175   else {
 176     lsx_fail_errno(ft,SOX_EFMT,"AVR: number of channels not supported");
 177     return(0);
 178   }
 179
 180   /* rez */
 181   if (ft->encoding.bits_per_sample == 8) {
 182     lsx_writew (ft, 8);
 183   }
 184   else if (ft->encoding.bits_per_sample == 16) {
 185     lsx_writew (ft, 16);
 186   }
 187   else {
 188     lsx_fail_errno(ft,SOX_EFMT,"AVR: unsupported sample resolution");
 189     return(SOX_EOF);
 190   }
 191
 192   /* sign */
 193   if (ft->encoding.encoding == SOX_ENCODING_SIGN2) {
 194     lsx_writew (ft, 0xffff);
 195   }
 196   else if (ft->encoding.encoding == SOX_ENCODING_UNSIGNED) {
 197     lsx_writew (ft, 0);
 198   }
 199   else {
 200     lsx_fail_errno(ft,SOX_EFMT,"AVR: unsupported encoding");
 201     return(SOX_EOF);
 202   }
 203
 204   /* loop */
 205   lsx_writew (ft, 0xffff);
 206
 207   /* midi */
 208   lsx_writew (ft, 0xffff);
 209
 210   /* rate */
 211   lsx_writedw(ft, (unsigned)(ft->signal.rate + .5));
 212
 213   /* size */
 214   /* Don't know the size yet. */
 215   lsx_writedw (ft, 0);
 216
 217   /* lbeg */
 218   lsx_writedw (ft, 0);
 219
 220   /* lend */
 221   /* Don't know the size yet, so we can't set lend, either. */
 222   lsx_writedw (ft, 0);
 223
 224   /* res1 */
 225   lsx_writew (ft, 0);
 226
 227   /* res2 */
 228   lsx_writew (ft, 0);
 229
 230   /* res3 */
 231   lsx_writew (ft, 0);
 232
 233   /* ext */
 234   lsx_writebuf(ft, "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0", sizeof(avr->ext));
 235
 236   /* user */
 237   lsx_writebuf(ft,
 238            "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"
 239            "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"
 240            "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"
 241            "\0\0\0\0", sizeof (avr->user));
 242
 243   return(SOX_SUCCESS);
 244 }
 245
 246 static size_t write_samples(sox_format_t * ft, const sox_sample_t *buf, size_t nsamp)
 247 {
 248   priv_t * avr = (priv_t *)ft->priv;
 249
 250   avr->size += nsamp;
 251
 252   return (lsx_rawwrite (ft, buf, nsamp));
 253 }
 254
 255 static int stopwrite(sox_format_t * ft)
 256 {
 257   priv_t * avr = (priv_t *)ft->priv;
 258
 259   unsigned size = avr->size / ft->signal.channels;
 260
 261   /* Fix size */
 262   lsx_seeki(ft, (off_t)26, SEEK_SET);
 263   lsx_writedw (ft, size);
 264
 265   /* Fix lend */
 266   lsx_seeki(ft, (off_t)34, SEEK_SET);
 267   lsx_writedw (ft, size);
 268
 269   return(SOX_SUCCESS);
 270 }
 271
 272 LSX_FORMAT_HANDLER(avr)
 273 {
 274   static char const * const names[] = { "avr", NULL };
 275   static unsigned const write_encodings[] = {
 276     SOX_ENCODING_SIGN2, 16, 8, 0,
 277     SOX_ENCODING_UNSIGNED, 16, 8, 0,
 278     0};
 279   static sox_format_handler_t handler = {SOX_LIB_VERSION_CODE,
 280     "Audio Visual Research format; used on the Mac",
 281     names, SOX_FILE_BIG_END | SOX_FILE_MONO | SOX_FILE_STEREO,
 282     startread, lsx_rawread, NULL,
 283     startwrite, write_samples, stopwrite,
 284     NULL, write_encodings, NULL, sizeof(priv_t)
 285   };
 286   return &handler;
 287 }