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/*
* 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;
}
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