summaryrefslogtreecommitdiffstats
path: root/apps/metadata/oma.c
blob: 1dd6150e33ec56078e68b02ccbf55a3fa3e6bd57 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
/*
 * Sony OpenMG (OMA) demuxer
 *
 * Copyright (c) 2008 Maxim Poliakovski
 *               2008 Benjamin Larsson
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * FFmpeg is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

/**
 * @file oma.c
 * This is a demuxer for Sony OpenMG Music files
 *
 * Known file extensions: ".oma", "aa3"
 * The format of such files consists of three parts:
 * - "ea3" header carrying overall info and metadata.
 * - "EA3" header is a Sony-specific header containing information about
 *   the OpenMG file: codec type (usually ATRAC, can also be MP3 or WMA),
 *   codec specific info (packet size, sample rate, channels and so on)
 *   and DRM related info (file encryption, content id).
 * - Sound data organized in packets follow the EA3 header
 *   (can be encrypted using the Sony DRM!).
 *
 * LIMITATIONS: This version supports only plain (unencrypted) OMA files.
 * If any DRM-protected (encrypted) file is encountered you will get the
 * corresponding error message. Try to remove the encryption using any
 * Sony software (for example SonicStage).
 * CODEC SUPPORT: Only ATRAC3 codec is currently supported!
 */

#include <stdlib.h>
#include <inttypes.h>
#include <string.h>
#include "metadata.h"
#include "metadata_parsers.h"

#define EA3_HEADER_SIZE 96

#if 0
#define DEBUGF printf
#else
#define DEBUGF(...)
#endif

/* Various helper macros taken from ffmpeg for reading *
 * and writing buffers with a specified endianess.     */
#   define AV_RB16(x)                           \
    ((((const uint8_t*)(x))[0] << 8) |          \
      ((const uint8_t*)(x))[1])
#   define AV_RB24(x)                           \
    ((((const uint8_t*)(x))[0] << 16) |         \
     (((const uint8_t*)(x))[1] <<  8) |         \
      ((const uint8_t*)(x))[2])
#   define AV_RB32(x)                           \
    ((((const uint8_t*)(x))[0] << 24) |         \
     (((const uint8_t*)(x))[1] << 16) |         \
     (((const uint8_t*)(x))[2] <<  8) |         \
      ((const uint8_t*)(x))[3])
#   define AV_WL32(p, d) do {                   \
        ((uint8_t*)(p))[0] = (d);               \
        ((uint8_t*)(p))[1] = (d)>>8;            \
        ((uint8_t*)(p))[2] = (d)>>16;           \
        ((uint8_t*)(p))[3] = (d)>>24;           \
    } while(0)
#   define AV_WL16(p, d) do {                   \
        ((uint8_t*)(p))[0] = (d);               \
        ((uint8_t*)(p))[1] = (d)>>8;            \
    } while(0)

/* Different codecs that could be present in a Sony OMA *
 * container file.                                      */
enum {
    OMA_CODECID_ATRAC3  = 0,
    OMA_CODECID_ATRAC3P = 1,
    OMA_CODECID_MP3     = 3,
    OMA_CODECID_LPCM    = 4,
    OMA_CODECID_WMA     = 5,
};

/* FIXME: This functions currently read different file *
 *        parameters required for decoding. It still   *
 *        does not read the metadata - which should be *
 *        present in the ea3 (first) header. The       *
 *        metadata in ea3 is stored as a variation of  *
 *        the ID3v2 metadata format.                   */
static int oma_read_header(int fd, struct mp3entry* id3)
{
    static const uint16_t srate_tab[6] = {320,441,480,882,960,0};
    int     ret, ea3_taglen, EA3_pos, jsflag;
    uint32_t codec_params;
    int16_t eid;
    uint8_t buf[EA3_HEADER_SIZE];

    ret = read(fd, buf, 10);
    if (ret != 10)
        return -1;

    ea3_taglen = ((buf[6] & 0x7f) << 21) | ((buf[7] & 0x7f) << 14) | ((buf[8] & 0x7f) << 7) | (buf[9] & 0x7f);

    EA3_pos = ea3_taglen + 10;
    if (buf[5] & 0x10)
        EA3_pos += 10;

    lseek(fd, EA3_pos, SEEK_SET);
    ret = read(fd, buf, EA3_HEADER_SIZE);
    if (ret != EA3_HEADER_SIZE)
        return -1;

    if (memcmp(buf, ((const uint8_t[]){'E', 'A', '3'}),3) || buf[4] != 0 || buf[5] != EA3_HEADER_SIZE) {
        DEBUGF("Couldn't find the EA3 header !\n");
        return -1;
    }

    eid = AV_RB16(&buf[6]);
    if (eid != -1 && eid != -128) {
        DEBUGF("Encrypted file! Eid: %d\n", eid);
        return -1;
    }

    codec_params = AV_RB24(&buf[33]);

    switch (buf[32]) {
        case OMA_CODECID_ATRAC3:
            id3->frequency = srate_tab[(codec_params >> 13) & 7]*100;
            if (id3->frequency != 44100) {
                DEBUGF("Unsupported sample rate, send sample file to developers: %d\n", id3->frequency);
                return -1;
            }

            id3->bytesperframe = (codec_params & 0x3FF) * 8;
            id3->codectype = AFMT_OMA_ATRAC3;
            jsflag = (codec_params >> 17) & 1; /* get stereo coding mode, 1 for joint-stereo */

            id3->bitrate = id3->frequency * id3->bytesperframe * 8 / (1024 * 1000);

            /* fake the atrac3 extradata (wav format, makes stream copy to wav work) */
            /* ATRAC3 expects and extra-data size of 14 bytes for wav format, and *
             * looks for that in the id3v2buf.                                    */
            id3->extradata_size = 14;
            AV_WL16(&id3->id3v2buf[0],  1);             // always 1
            AV_WL32(&id3->id3v2buf[2],  id3->frequency);    // samples rate
            AV_WL16(&id3->id3v2buf[6],  jsflag);        // coding mode
            AV_WL16(&id3->id3v2buf[8],  jsflag);        // coding mode
            AV_WL16(&id3->id3v2buf[10], 1);             // always 1
            AV_WL16(&id3->id3v2buf[12], 0);             // always 0

            id3->channels = 2;
            DEBUGF("sample_rate = %d\n", id3->frequency);
            DEBUGF("frame_size = %d\n", id3->bytesperframe);
            DEBUGF("stereo_coding_mode = %d\n", jsflag);
            break;
        default:
            DEBUGF("Unsupported codec %d!\n",buf[32]);
            return -1;
            break;
    }

    /* Store the the offset of the first audio frame, to be able to seek to it *
     * directly in atrac3_oma.codec.                                           */
    id3->first_frame_offset = EA3_pos + EA3_HEADER_SIZE; 
    return 0;
}

bool get_oma_metadata(int fd, struct mp3entry* id3)
{
    if(oma_read_header(fd, id3) < 0)
        return false;

    /* Currently, there's no means of knowing the duration *
     * directly from the the file so we calculate it.      */
    id3->filesize = filesize(fd);
    id3->length   = ((id3->filesize - id3->first_frame_offset) * 8) / id3->bitrate;
    return true;
}