apps/metadata/oma.c

   1 /*
   2  * Sony OpenMG (OMA) demuxer
   3  *
   4  * Copyright (c) 2008 Maxim Poliakovski
   5  *               2008 Benjamin Larsson
   6  *
   7  * This file is part of FFmpeg.
   8  *
   9  * FFmpeg is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU Lesser General Public
  11  * License as published by the Free Software Foundation; either
  12  * version 2.1 of the License, or (at your option) any later version.
  13  *
  14  * FFmpeg is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  * Lesser General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU Lesser General Public
  20  * License along with FFmpeg; if not, write to the Free Software
  21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  22  */
  23
  24 /**
  25  * @file oma.c
  26  * This is a demuxer for Sony OpenMG Music files
  27  *
  28  * Known file extensions: ".oma", "aa3"
  29  * The format of such files consists of three parts:
  30  * - "ea3" header carrying overall info and metadata.
  31  * - "EA3" header is a Sony-specific header containing information about
  32  *   the OpenMG file: codec type (usually ATRAC, can also be MP3 or WMA),
  33  *   codec specific info (packet size, sample rate, channels and so on)
  34  *   and DRM related info (file encryption, content id).
  35  * - Sound data organized in packets follow the EA3 header
  36  *   (can be encrypted using the Sony DRM!).
  37  *
  38  * LIMITATIONS: This version supports only plain (unencrypted) OMA files.
  39  * If any DRM-protected (encrypted) file is encountered you will get the
  40  * corresponding error message. Try to remove the encryption using any
  41  * Sony software (for example SonicStage).
  42  * CODEC SUPPORT: Only ATRAC3 codec is currently supported!
  43  */
  44
  45 #include <stdlib.h>
  46 #include <inttypes.h>
  47 #include <string.h>
  48 #include "metadata.h"
  49 #include "metadata_parsers.h"
  50
  51 #define EA3_HEADER_SIZE 96
  52
  53 #if 0
  54 #define DEBUGF printf
  55 #else
  56 #define DEBUGF(...)
  57 #endif
  58
  59 /* Various helper macros taken from ffmpeg for reading *
  60  * and writing buffers with a specified endianess.     */
  61 #   define AV_RB16(x)                           \
  62     ((((const uint8_t*)(x))[0] << 8) |          \
  63       ((const uint8_t*)(x))[1])
  64 #   define AV_RB24(x)                           \
  65     ((((const uint8_t*)(x))[0] << 16) |         \
  66      (((const uint8_t*)(x))[1] <<  8) |         \
  67       ((const uint8_t*)(x))[2])
  68 #   define AV_RB32(x)                           \
  69     ((((const uint8_t*)(x))[0] << 24) |         \
  70      (((const uint8_t*)(x))[1] << 16) |         \
  71      (((const uint8_t*)(x))[2] <<  8) |         \
  72       ((const uint8_t*)(x))[3])
  73 #   define AV_WL32(p, d) do {                   \
  74         ((uint8_t*)(p))[0] = (d);               \
  75         ((uint8_t*)(p))[1] = (d)>>8;            \
  76         ((uint8_t*)(p))[2] = (d)>>16;           \
  77         ((uint8_t*)(p))[3] = (d)>>24;           \
  78     } while(0)
  79 #   define AV_WL16(p, d) do {                   \
  80         ((uint8_t*)(p))[0] = (d);               \
  81         ((uint8_t*)(p))[1] = (d)>>8;            \
  82     } while(0)
  83
  84 /* Different codecs that could be present in a Sony OMA *
  85  * container file.                                      */
  86 enum {
  87     OMA_CODECID_ATRAC3  = 0,
  88     OMA_CODECID_ATRAC3P = 1,
  89     OMA_CODECID_MP3     = 3,
  90     OMA_CODECID_LPCM    = 4,
  91     OMA_CODECID_WMA     = 5,
  92 };
  93
  94 /* FIXME: This functions currently read different file *
  95  *        parameters required for decoding. It still   *
  96  *        does not read the metadata - which should be *
  97  *        present in the ea3 (first) header. The       *
  98  *        metadata in ea3 is stored as a variation of  *
  99  *        the ID3v2 metadata format.                   */
 100 static int oma_read_header(int fd, struct mp3entry* id3)
 101 {
 102     static const uint16_t srate_tab[6] = {320,441,480,882,960,0};
 103     int     ret, ea3_taglen, EA3_pos, jsflag;
 104     uint32_t codec_params;
 105     int16_t eid;
 106     uint8_t buf[EA3_HEADER_SIZE];
 107
 108     ret = read(fd, buf, 10);
 109     if (ret != 10)
 110         return -1;
 111
 112     ea3_taglen = ((buf[6] & 0x7f) << 21) | ((buf[7] & 0x7f) << 14) | ((buf[8] & 0x7f) << 7) | (buf[9] & 0x7f);
 113
 114     EA3_pos = ea3_taglen + 10;
 115     if (buf[5] & 0x10)
 116         EA3_pos += 10;
 117
 118     lseek(fd, EA3_pos, SEEK_SET);
 119     ret = read(fd, buf, EA3_HEADER_SIZE);
 120     if (ret != EA3_HEADER_SIZE)
 121         return -1;
 122
 123     if (memcmp(buf, ((const uint8_t[]){'E', 'A', '3'}),3) || buf[4] != 0 || buf[5] != EA3_HEADER_SIZE) {
 124         DEBUGF("Couldn't find the EA3 header !\n");
 125         return -1;
 126     }
 127
 128     eid = AV_RB16(&buf[6]);
 129     if (eid != -1 && eid != -128) {
 130         DEBUGF("Encrypted file! Eid: %d\n", eid);
 131         return -1;
 132     }
 133
 134     codec_params = AV_RB24(&buf[33]);
 135
 136     switch (buf[32]) {
 137         case OMA_CODECID_ATRAC3:
 138             id3->frequency = srate_tab[(codec_params >> 13) & 7]*100;
 139             if (id3->frequency != 44100) {
 140                 DEBUGF("Unsupported sample rate, send sample file to developers: %d\n", id3->frequency);
 141                 return -1;
 142             }
 143
 144             id3->bytesperframe = (codec_params & 0x3FF) * 8;
 145             id3->codectype = AFMT_OMA_ATRAC3;
 146             jsflag = (codec_params >> 17) & 1; /* get stereo coding mode, 1 for joint-stereo */
 147
 148             id3->bitrate = id3->frequency * id3->bytesperframe * 8 / (1024 * 1000);
 149
 150             /* fake the atrac3 extradata (wav format, makes stream copy to wav work) */
 151             /* ATRAC3 expects and extra-data size of 14 bytes for wav format, and *
 152              * looks for that in the id3v2buf.                                    */
 153             id3->extradata_size = 14;
 154             AV_WL16(&id3->id3v2buf[0],  1);             // always 1
 155             AV_WL32(&id3->id3v2buf[2],  id3->frequency);    // samples rate
 156             AV_WL16(&id3->id3v2buf[6],  jsflag);        // coding mode
 157             AV_WL16(&id3->id3v2buf[8],  jsflag);        // coding mode
 158             AV_WL16(&id3->id3v2buf[10], 1);             // always 1
 159             AV_WL16(&id3->id3v2buf[12], 0);             // always 0
 160
 161             id3->channels = 2;
 162             DEBUGF("sample_rate = %d\n", id3->frequency);
 163             DEBUGF("frame_size = %d\n", id3->bytesperframe);
 164             DEBUGF("stereo_coding_mode = %d\n", jsflag);
 165             break;
 166         default:
 167             DEBUGF("Unsupported codec %d!\n",buf[32]);
 168             return -1;
 169             break;
 170     }
 171
 172     /* Store the the offset of the first audio frame, to be able to seek to it *
 173      * directly in atrac3_oma.codec.                                           */
 174     id3->first_frame_offset = EA3_pos + EA3_HEADER_SIZE;
 175     return 0;
 176 }
 177
 178 bool get_oma_metadata(int fd, struct mp3entry* id3)
 179 {
 180     if(oma_read_header(fd, id3) < 0)
 181         return false;
 182
 183     /* Currently, there's no means of knowing the duration *
 184      * directly from the the file so we calculate it.      */
 185     id3->filesize = filesize(fd);
 186     id3->length   = ((id3->filesize - id3->first_frame_offset) * 8) / id3->bitrate;
 187     return true;
 188 }