FFmpeg
aac.h
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1 /*
2  * AAC definitions and structures
3  * Copyright (c) 2005-2006 Oded Shimon ( ods15 ods15 dyndns org )
4  * Copyright (c) 2006-2007 Maxim Gavrilov ( maxim.gavrilov gmail com )
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 /**
24  * @file
25  * AAC definitions and structures
26  * @author Oded Shimon ( ods15 ods15 dyndns org )
27  * @author Maxim Gavrilov ( maxim.gavrilov gmail com )
28  */
29 
30 #ifndef AVCODEC_AAC_H
31 #define AVCODEC_AAC_H
32 
33 
34 #include "aac_defines.h"
35 
36 #define MAX_CHANNELS 64
37 #define MAX_ELEM_ID 16
38 
39 #define TNS_MAX_ORDER 20
40 #define MAX_LTP_LONG_SFB 40
41 
51 };
52 
58  EXT_SBR_DATA = 0xd,
60 };
61 
67 };
68 
69 enum BandType {
70  ZERO_BT = 0, ///< Scalefactors and spectral data are all zero.
71  FIRST_PAIR_BT = 5, ///< This and later band types encode two values (rather than four) with one code word.
72  ESC_BT = 11, ///< Spectral data are coded with an escape sequence.
73  RESERVED_BT = 12, ///< Band types following are encoded differently from others.
74  NOISE_BT = 13, ///< Spectral data are scaled white noise not coded in the bitstream.
75  INTENSITY_BT2 = 14, ///< Scalefactor data are intensity stereo positions (out of phase).
76  INTENSITY_BT = 15, ///< Scalefactor data are intensity stereo positions (in phase).
77 };
78 
86 };
87 
88 /**
89  * Predictor State
90  */
91 typedef struct PredictorState {
101 
102 #define MAX_PREDICTORS 672
103 
104 #define SCALE_DIV_512 36 ///< scalefactor difference that corresponds to scale difference in 512 times
105 #define SCALE_ONE_POS 140 ///< scalefactor index that corresponds to scale=1.0
106 #define SCALE_MAX_POS 255 ///< scalefactor index maximum value
107 #define SCALE_MAX_DIFF 60 ///< maximum scalefactor difference allowed by standard
108 #define SCALE_DIFF_ZERO 60 ///< codebook index corresponding to zero scalefactor indices difference
109 
110 #define POW_SF2_ZERO 200 ///< ff_aac_pow2sf_tab index corresponding to pow(2, 0);
111 
112 #define NOISE_PRE 256 ///< preamble for NOISE_BT, put in bitstream with the first noise band
113 #define NOISE_PRE_BITS 9 ///< length of preamble
114 #define NOISE_OFFSET 90 ///< subtracted from global gain, used as offset for the preamble
115 
116 typedef struct Pulse {
118  int start;
119  int pos[4];
120  int amp[4];
121 } Pulse;
122 
123 #endif /* AVCODEC_AAC_H */
AAC_CHANNEL_BACK
@ AAC_CHANNEL_BACK
Definition: aac.h:83
TYPE_FIL
@ TYPE_FIL
Definition: aac.h:49
EXT_FILL
@ EXT_FILL
Definition: aac.h:54
Pulse::num_pulse
int num_pulse
Definition: aac.h:117
PredictorState::var1
AAC_FLOAT var1
Definition: aac.h:95
PredictorState::var0
AAC_FLOAT var0
Definition: aac.h:94
TYPE_PCE
@ TYPE_PCE
Definition: aac.h:48
EXT_DYNAMIC_RANGE
@ EXT_DYNAMIC_RANGE
Definition: aac.h:57
TYPE_CPE
@ TYPE_CPE
Definition: aac.h:44
Pulse::amp
int amp[4]
Definition: aac.h:120
Pulse::pos
int pos[4]
Definition: aac.h:119
Pulse::start
int start
Definition: aac.h:118
PredictorState::r0
AAC_FLOAT r0
Definition: aac.h:96
ZERO_BT
@ ZERO_BT
Scalefactors and spectral data are all zero.
Definition: aac.h:70
NOISE_BT
@ NOISE_BT
Spectral data are scaled white noise not coded in the bitstream.
Definition: aac.h:74
EIGHT_SHORT_SEQUENCE
@ EIGHT_SHORT_SEQUENCE
Definition: aac.h:65
INTENSITY_BT2
@ INTENSITY_BT2
Scalefactor data are intensity stereo positions (out of phase).
Definition: aac.h:75
TYPE_DSE
@ TYPE_DSE
Definition: aac.h:47
PredictorState
Predictor State.
Definition: aac.h:91
ChannelPosition
ChannelPosition
Definition: aac.h:79
INTENSITY_BT
@ INTENSITY_BT
Scalefactor data are intensity stereo positions (in phase).
Definition: aac.h:76
AAC_CHANNEL_SIDE
@ AAC_CHANNEL_SIDE
Definition: aac.h:82
AAC_CHANNEL_FRONT
@ AAC_CHANNEL_FRONT
Definition: aac.h:81
PredictorState::k1
AAC_FLOAT k1
Definition: aac.h:98
AAC_CHANNEL_OFF
@ AAC_CHANNEL_OFF
Definition: aac.h:80
PredictorState::r1
AAC_FLOAT r1
Definition: aac.h:97
ONLY_LONG_SEQUENCE
@ ONLY_LONG_SEQUENCE
Definition: aac.h:63
TYPE_END
@ TYPE_END
Definition: aac.h:50
BandType
BandType
Definition: aac.h:69
ESC_BT
@ ESC_BT
Spectral data are coded with an escape sequence.
Definition: aac.h:72
EXT_FILL_DATA
@ EXT_FILL_DATA
Definition: aac.h:55
RawDataBlockType
RawDataBlockType
Definition: aac.h:42
LONG_STOP_SEQUENCE
@ LONG_STOP_SEQUENCE
Definition: aac.h:66
PredictorState::x_est
AAC_FLOAT x_est
Definition: aac.h:99
TYPE_LFE
@ TYPE_LFE
Definition: aac.h:46
TYPE_SCE
@ TYPE_SCE
Definition: aac.h:43
AAC_CHANNEL_LFE
@ AAC_CHANNEL_LFE
Definition: aac.h:84
RESERVED_BT
@ RESERVED_BT
Band types following are encoded differently from others.
Definition: aac.h:73
LONG_START_SEQUENCE
@ LONG_START_SEQUENCE
Definition: aac.h:64
EXT_SBR_DATA_CRC
@ EXT_SBR_DATA_CRC
Definition: aac.h:59
EXT_SBR_DATA
@ EXT_SBR_DATA
Definition: aac.h:58
FIRST_PAIR_BT
@ FIRST_PAIR_BT
This and later band types encode two values (rather than four) with one code word.
Definition: aac.h:71
TYPE_CCE
@ TYPE_CCE
Definition: aac.h:45
PredictorState::cor1
AAC_FLOAT cor1
Definition: aac.h:93
AAC_FLOAT
float AAC_FLOAT
Definition: aac_defines.h:84
ExtensionPayloadID
ExtensionPayloadID
Definition: aac.h:53
EXT_DATA_ELEMENT
@ EXT_DATA_ELEMENT
Definition: aac.h:56
aac_defines.h
Pulse
Definition: aac.h:116
AAC_CHANNEL_CC
@ AAC_CHANNEL_CC
Definition: aac.h:85
WindowSequence
WindowSequence
Definition: aac.h:62
PredictorState::cor0
AAC_FLOAT cor0
Definition: aac.h:92