apps/metadata/adx.c

   1 /***************************************************************************
   2  *             __________               __   ___.
   3  *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
   4  *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
   5  *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
   6  *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
   7  *                     \/            \/     \/    \/            \/
   8  * $Id$
   9  *
  10  * Copyright (C) 2005 Dave Chapman
  11  *
  12  * All files in this archive are subject to the GNU General Public License.
  13  * See the file COPYING in the source tree root for full license agreement.
  14  *
  15  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
  16  * KIND, either express or implied.
  17  *
  18  ****************************************************************************/
  19 #include <stdio.h>
  20 #include <string.h>
  21 #include <stdlib.h>
  22 #include <ctype.h>
  23 #include <inttypes.h>
  24
  25 #include "system.h"
  26 #include "id3.h"
  27 #include "metadata_common.h"
  28 #include "debug.h"
  29
  30 bool get_adx_metadata(int fd, struct mp3entry* id3)
  31 {
  32     /* Use the trackname part of the id3 structure as a temporary buffer */
  33     unsigned char * buf = (unsigned char *)id3->path;
  34     int chanstart, channels, read_bytes;
  35     int looping = 0, start_adr = 0, end_adr = 0;
  36
  37     /* try to get the basic header */
  38     if ((lseek(fd, 0, SEEK_SET) < 0)
  39         || ((read_bytes = read(fd, buf, 0x38)) < 0x38))
  40     {
  41         DEBUGF("lseek or read failed\n");
  42         return false;
  43     }
  44
  45     /* ADX starts with 0x80 */
  46     if (buf[0] != 0x80) {
  47         DEBUGF("get_adx_metadata: wrong first byte %c\n",buf[0]);
  48         return false;
  49     }
  50
  51     /* check for a reasonable offset */
  52     chanstart = ((buf[2] << 8) | buf[3]) + 4;
  53     if (chanstart > 4096) {
  54         DEBUGF("get_adx_metadata: bad chanstart %i\n", chanstart);
  55         return false;
  56     }
  57
  58     /* check for a workable number of channels */
  59     channels = buf[7];
  60     if (channels != 1 && channels != 2) {
  61         DEBUGF("get_adx_metadata: bad channel count %i\n",channels);
  62         return false;
  63     }
  64
  65     id3->frequency = get_long_be(&buf[8]);
  66     /* 32 samples per 18 bytes */
  67     id3->bitrate = id3->frequency * channels * 18 * 8 / 32 / 1000;
  68     id3->length = get_long_be(&buf[12]) / id3->frequency * 1000;
  69     id3->vbr = false;
  70     id3->filesize = filesize(fd);
  71
  72     /* get loop info */
  73     if (!memcmp(buf+0x10,"\x01\xF4\x03\x00",4)) {
  74         /* Soul Calibur 2 style (type 03) */
  75         DEBUGF("get_adx_metadata: type 03 found\n");
  76         /* check if header is too small for loop data */
  77         if (chanstart-6 < 0x2c) looping=0;
  78         else {
  79             looping = get_long_be(&buf[0x18]);
  80             end_adr = get_long_be(&buf[0x28]);
  81             start_adr = get_long_be(&buf[0x1c])/32*channels*18+chanstart;
  82         }
  83     } else if (!memcmp(buf+0x10,"\x01\xF4\x04\x00",4)) {
  84         /* Standard (type 04) */
  85         DEBUGF("get_adx_metadata: type 04 found\n");
  86         /* check if header is too small for loop data */
  87         if (chanstart-6 < 0x38) looping=0;
  88         else {
  89             looping = get_long_be(&buf[0x24]);
  90             end_adr = get_long_be(&buf[0x34]);
  91             start_adr = get_long_be(&buf[0x28])/32*channels*18+chanstart;
  92         }
  93     } else {
  94         DEBUGF("get_adx_metadata: error, couldn't determine ADX type\n");
  95         return false;
  96     }
  97
  98     if (looping) {
  99         /* 2 loops, 10 second fade */
 100         id3->length = (start_adr-chanstart + 2*(end_adr-start_adr))
 101                       *8 / id3->bitrate + 10000;
 102     }
 103
 104     /* try to get the channel header */
 105     if ((lseek(fd, chanstart-6, SEEK_SET) < 0)
 106         || ((read_bytes = read(fd, buf, 6)) < 6))
 107     {
 108         return false;
 109     }
 110
 111     /* check channel header */
 112     if (memcmp(buf, "(c)CRI", 6) != 0) return false;
 113
 114     return true;
 115 }