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videolan
vlc-gpu
Commits
933abd7b
Commit
933abd7b
authored
Apr 13, 2009
by
Laurent Aimar
Browse files
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Plain Diff
Split out a52 parsing functions into a52.h
parent
2479ed41
Changes
2
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Showing
2 changed files
with
250 additions
and
195 deletions
+250
-195
modules/codec/a52.c
modules/codec/a52.c
+23
-195
modules/codec/a52.h
modules/codec/a52.h
+227
-0
No files found.
modules/codec/a52.c
View file @
933abd7b
...
...
@@ -35,7 +35,8 @@
#include <vlc_codec.h>
#include <vlc_aout.h>
#include <vlc_block_helper.h>
#include <vlc_bits.h>
#include "a52.h"
/*****************************************************************************
* Module descriptor
...
...
@@ -61,8 +62,6 @@ vlc_module_end ()
* decoder_sys_t : decoder descriptor
*****************************************************************************/
#define A52_HEADER_SIZE 7
struct
decoder_sys_t
{
/* Module mode */
...
...
@@ -81,8 +80,8 @@ struct decoder_sys_t
audio_date_t
end_date
;
mtime_t
i_pts
;
int
i_frame_size
,
i_bit_rate
;
unsigned
int
i_rate
,
i_channels
,
i_channels_conf
;
vlc_a52_header_t
frame
;
};
enum
{
...
...
@@ -100,9 +99,6 @@ enum {
****************************************************************************/
static
void
*
DecodeBlock
(
decoder_t
*
,
block_t
**
);
static
int
SyncInfo
(
const
uint8_t
*
,
unsigned
int
*
,
unsigned
int
*
,
unsigned
int
*
,
int
*
);
static
uint8_t
*
GetOutBuffer
(
decoder_t
*
,
void
**
);
static
aout_buffer_t
*
GetAoutBuffer
(
decoder_t
*
);
static
block_t
*
GetSoutBuffer
(
decoder_t
*
);
...
...
@@ -179,7 +175,7 @@ static int OpenPacketizer( vlc_object_t *p_this )
static
void
*
DecodeBlock
(
decoder_t
*
p_dec
,
block_t
**
pp_block
)
{
decoder_sys_t
*
p_sys
=
p_dec
->
p_sys
;
uint8_t
p_header
[
A52_HEADER_SIZE
];
uint8_t
p_header
[
VLC_
A52_HEADER_SIZE
];
uint8_t
*
p_buf
;
void
*
p_out_buffer
;
...
...
@@ -240,27 +236,23 @@ static void *DecodeBlock( decoder_t *p_dec, block_t **pp_block )
p_sys
->
i_state
=
STATE_HEADER
;
case
STATE_HEADER
:
/* Get A/52 frame header (A52_HEADER_SIZE bytes) */
/* Get A/52 frame header (
VLC_
A52_HEADER_SIZE bytes) */
if
(
block_PeekBytes
(
&
p_sys
->
bytestream
,
p_header
,
A52_HEADER_SIZE
)
!=
VLC_SUCCESS
)
VLC_
A52_HEADER_SIZE
)
!=
VLC_SUCCESS
)
{
/* Need more data */
return
NULL
;
}
/* Check if frame is valid and get frame info */
p_sys
->
i_frame_size
=
SyncInfo
(
p_header
,
&
p_sys
->
i_channels
,
&
p_sys
->
i_channels_conf
,
&
p_sys
->
i_rate
,
&
p_sys
->
i_bit_rate
);
if
(
!
p_sys
->
i_frame_size
)
if
(
vlc_a52_header_Parse
(
&
p_sys
->
frame
,
p_header
,
VLC_A52_HEADER_SIZE
)
)
{
msg_Dbg
(
p_dec
,
"emulated sync word"
);
block_SkipByte
(
&
p_sys
->
bytestream
);
p_sys
->
i_state
=
STATE_NOSYNC
;
break
;
}
p_sys
->
i_state
=
STATE_NEXT_SYNC
;
case
STATE_NEXT_SYNC
:
...
...
@@ -269,7 +261,7 @@ static void *DecodeBlock( decoder_t *p_dec, block_t **pp_block )
/* Check if next expected frame contains the sync word */
if
(
block_PeekOffsetBytes
(
&
p_sys
->
bytestream
,
p_sys
->
i_frame
_size
,
p_header
,
2
)
p_sys
->
frame
.
i
_size
,
p_header
,
2
)
!=
VLC_SUCCESS
)
{
/* Need more data */
...
...
@@ -299,7 +291,7 @@ static void *DecodeBlock( decoder_t *p_dec, block_t **pp_block )
/* Make sure we have enough data.
* (Not useful if we went through NEXT_SYNC) */
if
(
block_WaitBytes
(
&
p_sys
->
bytestream
,
p_sys
->
i_frame
_size
)
!=
VLC_SUCCESS
)
p_sys
->
frame
.
i
_size
)
!=
VLC_SUCCESS
)
{
/* Need more data */
return
NULL
;
...
...
@@ -315,7 +307,7 @@ static void *DecodeBlock( decoder_t *p_dec, block_t **pp_block )
/* Copy the whole frame into the buffer. When we reach this point
* we already know we have enough data available. */
block_GetBytes
(
&
p_sys
->
bytestream
,
p_buf
,
p_sys
->
i_frame
_size
);
block_GetBytes
(
&
p_sys
->
bytestream
,
p_buf
,
p_sys
->
frame
.
i
_size
);
/* Make sure we don't reuse the same pts twice */
if
(
p_sys
->
i_pts
==
p_sys
->
bytestream
.
p_block
->
i_pts
)
...
...
@@ -354,26 +346,26 @@ static uint8_t *GetOutBuffer( decoder_t *p_dec, void **pp_out_buffer )
decoder_sys_t
*
p_sys
=
p_dec
->
p_sys
;
uint8_t
*
p_buf
;
if
(
p_dec
->
fmt_out
.
audio
.
i_rate
!=
p_sys
->
i_rate
)
if
(
p_dec
->
fmt_out
.
audio
.
i_rate
!=
p_sys
->
frame
.
i_rate
)
{
msg_Info
(
p_dec
,
"A/52 channels:%d samplerate:%d bitrate:%d"
,
p_sys
->
i_channels
,
p_sys
->
i_rate
,
p_sys
->
i_bit_
rate
);
p_sys
->
frame
.
i_channels
,
p_sys
->
frame
.
i_rate
,
p_sys
->
frame
.
i_bit
rate
);
aout_DateInit
(
&
p_sys
->
end_date
,
p_sys
->
i_rate
);
aout_DateInit
(
&
p_sys
->
end_date
,
p_sys
->
frame
.
i_rate
);
aout_DateSet
(
&
p_sys
->
end_date
,
p_sys
->
i_pts
);
}
p_dec
->
fmt_out
.
audio
.
i_rate
=
p_sys
->
i_rate
;
p_dec
->
fmt_out
.
audio
.
i_channels
=
p_sys
->
i_channels
;
if
(
p_dec
->
fmt_out
.
audio
.
i_bytes_per_frame
<
p_sys
->
i_frame
_size
)
p_dec
->
fmt_out
.
audio
.
i_bytes_per_frame
=
p_sys
->
i_frame
_size
;
p_dec
->
fmt_out
.
audio
.
i_rate
=
p_sys
->
frame
.
i_rate
;
p_dec
->
fmt_out
.
audio
.
i_channels
=
p_sys
->
frame
.
i_channels
;
if
(
p_dec
->
fmt_out
.
audio
.
i_bytes_per_frame
<
p_sys
->
frame
.
i
_size
)
p_dec
->
fmt_out
.
audio
.
i_bytes_per_frame
=
p_sys
->
frame
.
i
_size
;
p_dec
->
fmt_out
.
audio
.
i_frame_length
=
A52_FRAME_NB
;
p_dec
->
fmt_out
.
audio
.
i_original_channels
=
p_sys
->
i_channels_conf
;
p_dec
->
fmt_out
.
audio
.
i_original_channels
=
p_sys
->
frame
.
i_channels_conf
;
p_dec
->
fmt_out
.
audio
.
i_physical_channels
=
p_sys
->
i_channels_conf
&
AOUT_CHAN_PHYSMASK
;
p_sys
->
frame
.
i_channels_conf
&
AOUT_CHAN_PHYSMASK
;
p_dec
->
fmt_out
.
i_bitrate
=
p_sys
->
i_bit_
rate
;
p_dec
->
fmt_out
.
i_bitrate
=
p_sys
->
frame
.
i_bit
rate
;
if
(
p_sys
->
b_packetizer
)
{
...
...
@@ -416,7 +408,7 @@ static block_t *GetSoutBuffer( decoder_t *p_dec )
decoder_sys_t
*
p_sys
=
p_dec
->
p_sys
;
block_t
*
p_block
;
p_block
=
block_New
(
p_dec
,
p_sys
->
i_frame
_size
);
p_block
=
block_New
(
p_dec
,
p_sys
->
frame
.
i
_size
);
if
(
p_block
==
NULL
)
return
NULL
;
p_block
->
i_pts
=
p_block
->
i_dts
=
aout_DateGet
(
&
p_sys
->
end_date
);
...
...
@@ -427,167 +419,3 @@ static block_t *GetSoutBuffer( decoder_t *p_dec )
return
p_block
;
}
/* Tables */
static
const
struct
{
unsigned
int
i_count
;
unsigned
int
i_configuration
;
}
p_acmod
[
8
]
=
{
{
2
,
AOUT_CHAN_LEFT
|
AOUT_CHAN_RIGHT
|
AOUT_CHAN_DUALMONO
},
/* Dual-channel 1+1 */
{
1
,
AOUT_CHAN_CENTER
},
/* Mono 1/0 */
{
2
,
AOUT_CHAN_LEFT
|
AOUT_CHAN_RIGHT
},
/* Stereo 2/0 */
{
3
,
AOUT_CHAN_LEFT
|
AOUT_CHAN_RIGHT
|
AOUT_CHAN_CENTER
},
/* 3F 3/0 */
{
3
,
AOUT_CHAN_LEFT
|
AOUT_CHAN_RIGHT
|
AOUT_CHAN_REARCENTER
},
/* 2F1R 2/1 */
{
4
,
AOUT_CHAN_LEFT
|
AOUT_CHAN_RIGHT
|
AOUT_CHAN_CENTER
|
AOUT_CHAN_REARCENTER
},
/* 3F1R 3/1 */
{
5
,
AOUT_CHAN_LEFT
|
AOUT_CHAN_RIGHT
|
AOUT_CHAN_REARLEFT
|
AOUT_CHAN_REARRIGHT
},
/* 2F2R 2/2 */
{
6
,
AOUT_CHAN_LEFT
|
AOUT_CHAN_RIGHT
|
AOUT_CHAN_CENTER
|
AOUT_CHAN_REARLEFT
|
AOUT_CHAN_REARRIGHT
},
/* 3F2R 3/2 */
};
/**
* It parse AC3 sync info.
*
* This code is borrowed from liba52 by Aaron Holtzman & Michel Lespinasse,
* since we don't want to oblige S/PDIF people to use liba52 just to get
* their SyncInfo...
*/
static
int
SyncInfoAC3
(
const
uint8_t
*
p_buf
,
unsigned
int
*
pi_channels
,
unsigned
int
*
pi_channels_conf
,
unsigned
int
*
pi_sample_rate
,
int
*
pi_bit_rate
)
{
static
const
uint8_t
halfrate
[
12
]
=
{
0
,
0
,
0
,
0
,
0
,
0
,
0
,
0
,
0
,
1
,
2
,
3
};
static
const
int
rate
[]
=
{
32
,
40
,
48
,
56
,
64
,
80
,
96
,
112
,
128
,
160
,
192
,
224
,
256
,
320
,
384
,
448
,
512
,
576
,
640
};
static
const
uint8_t
lfeon
[
8
]
=
{
0x10
,
0x10
,
0x04
,
0x04
,
0x04
,
0x01
,
0x04
,
0x01
};
int
frmsizecod
;
int
bitrate
;
int
half
;
int
acmod
;
/* */
half
=
halfrate
[
p_buf
[
5
]
>>
3
];
/* acmod, dsurmod and lfeon */
acmod
=
p_buf
[
6
]
>>
5
;
if
(
(
p_buf
[
6
]
&
0xf8
)
==
0x50
)
{
/* Dolby surround = stereo + Dolby */
*
pi_channels
=
2
;
*
pi_channels_conf
=
AOUT_CHAN_LEFT
|
AOUT_CHAN_RIGHT
|
AOUT_CHAN_DOLBYSTEREO
;
}
else
{
*
pi_channels
=
p_acmod
[
acmod
].
i_count
;
*
pi_channels_conf
=
p_acmod
[
acmod
].
i_configuration
;
}
if
(
p_buf
[
6
]
&
lfeon
[
acmod
]
)
{
(
*
pi_channels
)
++
;
*
pi_channels_conf
|=
AOUT_CHAN_LFE
;
}
frmsizecod
=
p_buf
[
4
]
&
63
;
if
(
frmsizecod
>=
38
)
return
0
;
bitrate
=
rate
[
frmsizecod
>>
1
];
*
pi_bit_rate
=
(
bitrate
*
1000
)
>>
half
;
switch
(
p_buf
[
4
]
&
0xc0
)
{
case
0
:
*
pi_sample_rate
=
48000
>>
half
;
return
4
*
bitrate
;
case
0x40
:
*
pi_sample_rate
=
44100
>>
half
;
return
2
*
(
320
*
bitrate
/
147
+
(
frmsizecod
&
1
));
case
0x80
:
*
pi_sample_rate
=
32000
>>
half
;
return
6
*
bitrate
;
default:
return
0
;
}
}
/**
* It parse E-AC3 sync info
*/
static
int
SyncInfoEAC3
(
const
uint8_t
*
p_buf
,
unsigned
int
*
pi_channels
,
unsigned
int
*
pi_channels_conf
,
unsigned
int
*
pi_sample_rate
,
int
*
pi_bit_rate
)
{
static
const
int
pi_samplerate
[
3
]
=
{
48000
,
44100
,
32000
};
bs_t
s
;
int
i_frame_size
;
int
i_fscod
,
i_fscod2
;
int
i_numblkscod
;
int
i_acmod
,
i_lfeon
;
int
i_bytes
;
bs_init
(
&
s
,
(
void
*
)
p_buf
,
A52_HEADER_SIZE
);
bs_skip
(
&
s
,
16
+
/* start code */
2
+
/* stream type */
3
);
/* substream id */
i_frame_size
=
bs_read
(
&
s
,
11
);
if
(
i_frame_size
<
2
)
return
0
;
i_bytes
=
2
*
(
i_frame_size
+
1
);
i_fscod
=
bs_read
(
&
s
,
2
);
if
(
i_fscod
==
0x03
)
{
i_fscod2
=
bs_read
(
&
s
,
2
);
if
(
i_fscod2
==
0X03
)
return
0
;
*
pi_sample_rate
=
pi_samplerate
[
i_fscod2
]
/
2
;
i_numblkscod
=
6
;
}
else
{
static
const
int
pi_blocks
[
4
]
=
{
1
,
2
,
3
,
6
};
*
pi_sample_rate
=
pi_samplerate
[
i_fscod
];
i_numblkscod
=
pi_blocks
[
bs_read
(
&
s
,
2
)];
}
i_acmod
=
bs_read
(
&
s
,
3
);
i_lfeon
=
bs_read1
(
&
s
);
*
pi_channels
=
p_acmod
[
i_acmod
].
i_count
+
i_lfeon
;
*
pi_channels_conf
=
p_acmod
[
i_acmod
].
i_configuration
|
(
i_lfeon
?
AOUT_CHAN_LFE
:
0
);
*
pi_bit_rate
=
8
*
i_bytes
*
(
*
pi_sample_rate
)
/
(
i_numblkscod
*
256
);
return
i_bytes
;
}
static
int
SyncInfo
(
const
uint8_t
*
p_buf
,
unsigned
int
*
pi_channels
,
unsigned
int
*
pi_channels_conf
,
unsigned
int
*
pi_sample_rate
,
int
*
pi_bit_rate
)
{
int
bsid
;
/* Check synword */
if
(
p_buf
[
0
]
!=
0x0b
||
p_buf
[
1
]
!=
0x77
)
return
0
;
/* Check bsid */
bsid
=
p_buf
[
5
]
>>
3
;
if
(
bsid
>
16
)
return
0
;
if
(
bsid
<=
10
)
return
SyncInfoAC3
(
p_buf
,
pi_channels
,
pi_channels_conf
,
pi_sample_rate
,
pi_bit_rate
);
else
return
SyncInfoEAC3
(
p_buf
,
pi_channels
,
pi_channels_conf
,
pi_sample_rate
,
pi_bit_rate
);
}
modules/codec/a52.h
0 → 100644
View file @
933abd7b
/*****************************************************************************
* a52.h
*****************************************************************************
* Copyright (C) 2001-2009 Laurent Aimar
* $Id$
*
* Authors: Stéphane Borel <stef@via.ecp.fr>
* Christophe Massiot <massiot@via.ecp.fr>
* Gildas Bazin <gbazin@videolan.org>
* Laurent Aimar <fenrir@via.ecp.fr>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
*****************************************************************************/
#ifndef _VLC_A52_H
#define _VLC_A52_H 1
#include <vlc_aout.h>
#include <vlc_bits.h>
typedef
struct
{
unsigned
int
i_count
;
unsigned
int
i_configuration
;
}
vlc_a52_acmod_t
;
/**
* Minimum AC3 header size that vlc_a52_header_Parse needs.
*/
#define VLC_A52_HEADER_SIZE (8)
/**
* AC3 header information.
*/
typedef
struct
{
bool
b_eac3
;
unsigned
int
i_channels
;
unsigned
int
i_channels_conf
;
unsigned
int
i_rate
;
unsigned
int
i_bitrate
;
unsigned
int
i_size
;
}
vlc_a52_header_t
;
/**
* It parse AC3 sync info.
*
* This code is borrowed from liba52 by Aaron Holtzman & Michel Lespinasse,
* since we don't want to oblige S/PDIF people to use liba52 just to get
* their SyncInfo...
*/
static
inline
int
vlc_a52_header_ParseAc3
(
vlc_a52_header_t
*
p_header
,
const
uint8_t
*
p_buf
,
const
vlc_a52_acmod_t
*
p_acmod
)
{
static
const
uint8_t
pi_halfrate
[
12
]
=
{
0
,
0
,
0
,
0
,
0
,
0
,
0
,
0
,
0
,
1
,
2
,
3
};
static
const
unsigned
int
pi_bitrate
[]
=
{
32
,
40
,
48
,
56
,
64
,
80
,
96
,
112
,
128
,
160
,
192
,
224
,
256
,
320
,
384
,
448
,
512
,
576
,
640
};
static
const
uint8_t
pi_lfeon
[
8
]
=
{
0x10
,
0x10
,
0x04
,
0x04
,
0x04
,
0x01
,
0x04
,
0x01
};
/* */
const
unsigned
i_rate_shift
=
pi_halfrate
[
p_buf
[
5
]
>>
3
];
/* acmod, dsurmod and lfeon */
const
unsigned
i_acmod
=
p_buf
[
6
]
>>
5
;
if
(
(
p_buf
[
6
]
&
0xf8
)
==
0x50
)
{
/* Dolby surround = stereo + Dolby */
p_header
->
i_channels
=
2
;
p_header
->
i_channels_conf
=
AOUT_CHAN_LEFT
|
AOUT_CHAN_RIGHT
|
AOUT_CHAN_DOLBYSTEREO
;
}
else
{
p_header
->
i_channels
=
p_acmod
[
i_acmod
].
i_count
;
p_header
->
i_channels_conf
=
p_acmod
[
i_acmod
].
i_configuration
;
}
if
(
p_buf
[
6
]
&
pi_lfeon
[
i_acmod
]
)
{
p_header
->
i_channels
++
;
p_header
->
i_channels_conf
|=
AOUT_CHAN_LFE
;
}
const
unsigned
i_frmsizecod
=
p_buf
[
4
]
&
63
;
if
(
i_frmsizecod
>=
38
)
return
VLC_EGENERIC
;
const
unsigned
i_bitrate_base
=
pi_bitrate
[
i_frmsizecod
>>
1
];
p_header
->
i_bitrate
=
(
i_bitrate_base
*
1000
)
>>
i_rate_shift
;
switch
(
p_buf
[
4
]
&
0xc0
)
{
case
0
:
p_header
->
i_rate
=
48000
>>
i_rate_shift
;
p_header
->
i_size
=
4
*
i_bitrate_base
;
break
;
case
0x40
:
p_header
->
i_rate
=
44100
>>
i_rate_shift
;
p_header
->
i_size
=
2
*
(
320
*
i_bitrate_base
/
147
+
(
i_frmsizecod
&
1
));
break
;
case
0x80
:
p_header
->
i_rate
=
32000
>>
i_rate_shift
;
p_header
->
i_size
=
6
*
i_bitrate_base
;
break
;
default:
return
VLC_EGENERIC
;
}
p_header
->
b_eac3
=
false
;
return
VLC_SUCCESS
;
}
/**
* It parse E-AC3 sync info
*/
static
inline
int
vlc_a52_header_ParseEac3
(
vlc_a52_header_t
*
p_header
,
const
uint8_t
*
p_buf
,
const
vlc_a52_acmod_t
*
p_acmod
)
{
static
const
unsigned
pi_samplerate
[
3
]
=
{
48000
,
44100
,
32000
};
unsigned
i_numblkscod
;
bs_t
s
;
bs_init
(
&
s
,
(
void
*
)
p_buf
,
VLC_A52_HEADER_SIZE
);
bs_skip
(
&
s
,
16
+
/* start code */
2
+
/* stream type */
3
);
/* substream id */
const
unsigned
i_frame_size
=
bs_read
(
&
s
,
11
);
if
(
i_frame_size
<
2
)
return
VLC_EGENERIC
;
p_header
->
i_size
=
2
*
(
i_frame_size
+
1
);
const
unsigned
i_fscod
=
bs_read
(
&
s
,
2
);
if
(
i_fscod
==
0x03
)
{
const
unsigned
i_fscod2
=
bs_read
(
&
s
,
2
);
if
(
i_fscod2
==
0X03
)
return
VLC_EGENERIC
;
p_header
->
i_rate
=
pi_samplerate
[
i_fscod2
]
/
2
;
i_numblkscod
=
6
;
}
else
{
static
const
int
pi_blocks
[
4
]
=
{
1
,
2
,
3
,
6
};
p_header
->
i_rate
=
pi_samplerate
[
i_fscod
];
i_numblkscod
=
pi_blocks
[
bs_read
(
&
s
,
2
)];
}
const
unsigned
i_acmod
=
bs_read
(
&
s
,
3
);
const
unsigned
i_lfeon
=
bs_read1
(
&
s
);
p_header
->
i_channels
=
p_acmod
[
i_acmod
].
i_count
+
i_lfeon
;
p_header
->
i_channels_conf
=
p_acmod
[
i_acmod
].
i_configuration
|
(
i_lfeon
?
AOUT_CHAN_LFE
:
0
);
p_header
->
i_bitrate
=
8
*
p_header
->
i_size
*
(
p_header
->
i_rate
)
/
(
i_numblkscod
*
256
);
p_header
->
b_eac3
=
true
;
return
VLC_SUCCESS
;
}
/**
* It will parse the header AC3 frame and fill vlc_a52_header_t* if
* it is valid or return VLC_EGENERIC.
*
* XXX It will only recognize big endian bitstream ie starting with 0x0b, 0x77
*/
static
inline
int
vlc_a52_header_Parse
(
vlc_a52_header_t
*
p_header
,
const
uint8_t
*
p_buffer
,
int
i_buffer
)
{
static
const
vlc_a52_acmod_t
p_acmod
[
8
]
=
{
{
2
,
AOUT_CHAN_LEFT
|
AOUT_CHAN_RIGHT
|
AOUT_CHAN_DUALMONO
},
/* Dual-channel 1+1 */
{
1
,
AOUT_CHAN_CENTER
},
/* Mono 1/0 */
{
2
,
AOUT_CHAN_LEFT
|
AOUT_CHAN_RIGHT
},
/* Stereo 2/0 */
{
3
,
AOUT_CHAN_LEFT
|
AOUT_CHAN_RIGHT
|
AOUT_CHAN_CENTER
},
/* 3F 3/0 */
{
3
,
AOUT_CHAN_LEFT
|
AOUT_CHAN_RIGHT
|
AOUT_CHAN_REARCENTER
},
/* 2F1R 2/1 */
{
4
,
AOUT_CHAN_LEFT
|
AOUT_CHAN_RIGHT
|
AOUT_CHAN_CENTER
|
AOUT_CHAN_REARCENTER
},
/* 3F1R 3/1 */
{
5
,
AOUT_CHAN_LEFT
|
AOUT_CHAN_RIGHT
|
AOUT_CHAN_REARLEFT
|
AOUT_CHAN_REARRIGHT
},
/* 2F2R 2/2 */
{
6
,
AOUT_CHAN_LEFT
|
AOUT_CHAN_RIGHT
|
AOUT_CHAN_CENTER
|
AOUT_CHAN_REARLEFT
|
AOUT_CHAN_REARRIGHT
},
/* 3F2R 3/2 */
};
if
(
i_buffer
<
VLC_A52_HEADER_SIZE
)
return
VLC_EGENERIC
;
/* Check synword */
if
(
p_buffer
[
0
]
!=
0x0b
||
p_buffer
[
1
]
!=
0x77
)
return
VLC_EGENERIC
;
/* Check bsid */
const
int
bsid
=
p_buffer
[
5
]
>>
3
;
if
(
bsid
>
16
)
return
VLC_EGENERIC
;
if
(
bsid
<=
10
)
{
if
(
vlc_a52_header_ParseAc3
(
p_header
,
p_buffer
,
p_acmod
)
)
return
VLC_EGENERIC
;
}
else
{
if
(
vlc_a52_header_ParseEac3
(
p_header
,
p_buffer
,
p_acmod
)
)
return
VLC_EGENERIC
;
}
return
VLC_SUCCESS
;
}
#endif
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