FFmpeg
mpeg4audio.h
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1 /*
2  * MPEG-4 Audio common header
3  * Copyright (c) 2008 Baptiste Coudurier <baptiste.coudurier@free.fr>
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #ifndef AVCODEC_MPEG4AUDIO_H
23 #define AVCODEC_MPEG4AUDIO_H
24 
25 #include <stdint.h>
26 
27 #include "libavutil/attributes.h"
28 
29 #include "get_bits.h"
30 #include "put_bits.h"
31 
32 typedef struct MPEG4AudioConfig {
37  int sbr; ///< -1 implicit, 1 presence
42  int channels;
43  int ps; ///< -1 implicit, 1 presence
46 
47 extern const int ff_mpeg4audio_sample_rates[16];
48 extern const uint8_t ff_mpeg4audio_channels[14];
49 
50 /**
51  * Parse MPEG-4 systems extradata from a potentially unaligned GetBitContext to retrieve audio configuration.
52  * @param[in] c MPEG4AudioConfig structure to fill.
53  * @param[in] gb Extradata from container.
54  * @param[in] sync_extension look for a sync extension after config if true.
55  * @param[in] logctx opaque struct starting with an AVClass element, used for logging.
56  * @return negative AVERROR code on error, on success AudioSpecificConfig bit index in extradata.
57  */
59  int sync_extension, void *logctx);
60 
61 /**
62  * Parse MPEG-4 systems extradata from a raw buffer to retrieve audio configuration.
63  * @param[in] c MPEG4AudioConfig structure to fill.
64  * @param[in] buf Extradata from container.
65  * @param[in] size Extradata size in bytes.
66  * @param[in] sync_extension look for a sync extension after config if true.
67  * @param[in] logctx opaque struct starting with an AVClass element, used for logging.
68  * @return negative AVERROR code on error, AudioSpecificConfig bit index in extradata on success.
69  */
70 int avpriv_mpeg4audio_get_config2(MPEG4AudioConfig *c, const uint8_t *buf,
71  int size, int sync_extension, void *logctx);
72 
75  // Support? Name
76  AOT_AAC_MAIN, ///< Y Main
77  AOT_AAC_LC, ///< Y Low Complexity
78  AOT_AAC_SSR, ///< N (code in SoC repo) Scalable Sample Rate
79  AOT_AAC_LTP, ///< Y Long Term Prediction
80  AOT_SBR, ///< Y Spectral Band Replication
81  AOT_AAC_SCALABLE, ///< N Scalable
82  AOT_TWINVQ, ///< N Twin Vector Quantizer
83  AOT_CELP, ///< N Code Excited Linear Prediction
84  AOT_HVXC, ///< N Harmonic Vector eXcitation Coding
85  AOT_TTSI = 12, ///< N Text-To-Speech Interface
86  AOT_MAINSYNTH, ///< N Main Synthesis
87  AOT_WAVESYNTH, ///< N Wavetable Synthesis
88  AOT_MIDI, ///< N General MIDI
89  AOT_SAFX, ///< N Algorithmic Synthesis and Audio Effects
90  AOT_ER_AAC_LC, ///< N Error Resilient Low Complexity
91  AOT_ER_AAC_LTP = 19, ///< N Error Resilient Long Term Prediction
92  AOT_ER_AAC_SCALABLE, ///< N Error Resilient Scalable
93  AOT_ER_TWINVQ, ///< N Error Resilient Twin Vector Quantizer
94  AOT_ER_BSAC, ///< N Error Resilient Bit-Sliced Arithmetic Coding
95  AOT_ER_AAC_LD, ///< N Error Resilient Low Delay
96  AOT_ER_CELP, ///< N Error Resilient Code Excited Linear Prediction
97  AOT_ER_HVXC, ///< N Error Resilient Harmonic Vector eXcitation Coding
98  AOT_ER_HILN, ///< N Error Resilient Harmonic and Individual Lines plus Noise
99  AOT_ER_PARAM, ///< N Error Resilient Parametric
100  AOT_SSC, ///< N SinuSoidal Coding
101  AOT_PS, ///< N Parametric Stereo
102  AOT_SURROUND, ///< N MPEG Surround
103  AOT_ESCAPE, ///< Y Escape Value
104  AOT_L1, ///< Y Layer 1
105  AOT_L2, ///< Y Layer 2
106  AOT_L3, ///< Y Layer 3
107  AOT_DST, ///< N Direct Stream Transfer
108  AOT_ALS, ///< Y Audio LosslesS
109  AOT_SLS, ///< N Scalable LosslesS
110  AOT_SLS_NON_CORE, ///< N Scalable LosslesS (non core)
111  AOT_ER_AAC_ELD, ///< N Error Resilient Enhanced Low Delay
112  AOT_SMR_SIMPLE, ///< N Symbolic Music Representation Simple
113  AOT_SMR_MAIN, ///< N Symbolic Music Representation Main
114  AOT_USAC_NOSBR, ///< N Unified Speech and Audio Coding (no SBR)
115  AOT_SAOC, ///< N Spatial Audio Object Coding
116  AOT_LD_SURROUND, ///< N Low Delay MPEG Surround
117  AOT_USAC, ///< N Unified Speech and Audio Coding
118 };
119 
120 #define MAX_PCE_SIZE 320 ///<Maximum size of a PCE including the 3-bit ID_PCE
121  ///<marker and the comment
122 
124  GetBitContext *gb,
125  int bits)
126 {
127  unsigned int el = get_bits(gb, bits);
128  put_bits(pb, bits, el);
129  return el;
130 }
131 
132 static inline int ff_copy_pce_data(PutBitContext *pb, GetBitContext *gb)
133 {
134  int five_bit_ch, four_bit_ch, comment_size, bits;
135  int offset = put_bits_count(pb);
136 
137  ff_pce_copy_bits(pb, gb, 10); // Tag, Object Type, Frequency
138  five_bit_ch = ff_pce_copy_bits(pb, gb, 4); // Front
139  five_bit_ch += ff_pce_copy_bits(pb, gb, 4); // Side
140  five_bit_ch += ff_pce_copy_bits(pb, gb, 4); // Back
141  four_bit_ch = ff_pce_copy_bits(pb, gb, 2); // LFE
142  four_bit_ch += ff_pce_copy_bits(pb, gb, 3); // Data
143  five_bit_ch += ff_pce_copy_bits(pb, gb, 4); // Coupling
144  if (ff_pce_copy_bits(pb, gb, 1)) // Mono Mixdown
145  ff_pce_copy_bits(pb, gb, 4);
146  if (ff_pce_copy_bits(pb, gb, 1)) // Stereo Mixdown
147  ff_pce_copy_bits(pb, gb, 4);
148  if (ff_pce_copy_bits(pb, gb, 1)) // Matrix Mixdown
149  ff_pce_copy_bits(pb, gb, 3);
150  for (bits = five_bit_ch*5+four_bit_ch*4; bits > 16; bits -= 16)
151  ff_pce_copy_bits(pb, gb, 16);
152  if (bits)
153  ff_pce_copy_bits(pb, gb, bits);
154  align_put_bits(pb);
155  align_get_bits(gb);
156  comment_size = ff_pce_copy_bits(pb, gb, 8);
157  for (; comment_size > 0; comment_size--)
158  ff_pce_copy_bits(pb, gb, 8);
159 
160  return put_bits_count(pb) - offset;
161 }
162 
163 #endif /* AVCODEC_MPEG4AUDIO_H */
align_put_bits
static void align_put_bits(PutBitContext *s)
Pad the bitstream with zeros up to the next byte boundary.
Definition: put_bits.h:413
AOT_PS
@ AOT_PS
N Parametric Stereo.
Definition: mpeg4audio.h:101
AOT_L1
@ AOT_L1
Y Layer 1.
Definition: mpeg4audio.h:104
put_bits
static void put_bits(Jpeg2000EncoderContext *s, int val, int n)
put n times val bit
Definition: j2kenc.c:221
AOT_ER_AAC_LTP
@ AOT_ER_AAC_LTP
N Error Resilient Long Term Prediction.
Definition: mpeg4audio.h:91
AOT_SLS_NON_CORE
@ AOT_SLS_NON_CORE
N Scalable LosslesS (non core)
Definition: mpeg4audio.h:110
AOT_SAFX
@ AOT_SAFX
N Algorithmic Synthesis and Audio Effects.
Definition: mpeg4audio.h:89
AOT_SURROUND
@ AOT_SURROUND
N MPEG Surround.
Definition: mpeg4audio.h:102
MPEG4AudioConfig
Definition: mpeg4audio.h:32
get_bits
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:380
AOT_CELP
@ AOT_CELP
N Code Excited Linear Prediction.
Definition: mpeg4audio.h:83
AOT_ER_PARAM
@ AOT_ER_PARAM
N Error Resilient Parametric.
Definition: mpeg4audio.h:99
AOT_ESCAPE
@ AOT_ESCAPE
Y Escape Value.
Definition: mpeg4audio.h:103
GetBitContext
Definition: get_bits.h:62
AOT_USAC_NOSBR
@ AOT_USAC_NOSBR
N Unified Speech and Audio Coding (no SBR)
Definition: mpeg4audio.h:114
AOT_SMR_MAIN
@ AOT_SMR_MAIN
N Symbolic Music Representation Main.
Definition: mpeg4audio.h:113
avpriv_mpeg4audio_get_config2
int avpriv_mpeg4audio_get_config2(MPEG4AudioConfig *c, const uint8_t *buf, int size, int sync_extension, void *logctx)
Parse MPEG-4 systems extradata from a raw buffer to retrieve audio configuration.
Definition: mpeg4audio.c:165
AOT_ER_AAC_LC
@ AOT_ER_AAC_LC
N Error Resilient Low Complexity.
Definition: mpeg4audio.h:90
AudioObjectType
AudioObjectType
Definition: mpeg4audio.h:73
AOT_ER_AAC_LD
@ AOT_ER_AAC_LD
N Error Resilient Low Delay.
Definition: mpeg4audio.h:95
AOT_SLS
@ AOT_SLS
N Scalable LosslesS.
Definition: mpeg4audio.h:109
bits
uint8_t bits
Definition: vp3data.h:141
AOT_MIDI
@ AOT_MIDI
N General MIDI.
Definition: mpeg4audio.h:88
AOT_ER_HILN
@ AOT_ER_HILN
N Error Resilient Harmonic and Individual Lines plus Noise.
Definition: mpeg4audio.h:98
get_bits.h
MPEG4AudioConfig::ext_chan_config
int ext_chan_config
Definition: mpeg4audio.h:41
AOT_TTSI
@ AOT_TTSI
N Text-To-Speech Interface.
Definition: mpeg4audio.h:85
PutBitContext
Definition: put_bits.h:50
AOT_ER_TWINVQ
@ AOT_ER_TWINVQ
N Error Resilient Twin Vector Quantizer.
Definition: mpeg4audio.h:93
MPEG4AudioConfig::sampling_index
int sampling_index
Definition: mpeg4audio.h:34
AOT_USAC
@ AOT_USAC
N Unified Speech and Audio Coding.
Definition: mpeg4audio.h:117
AOT_MAINSYNTH
@ AOT_MAINSYNTH
N Main Synthesis.
Definition: mpeg4audio.h:86
ff_pce_copy_bits
static av_always_inline unsigned int ff_pce_copy_bits(PutBitContext *pb, GetBitContext *gb, int bits)
Definition: mpeg4audio.h:123
ff_copy_pce_data
static int ff_copy_pce_data(PutBitContext *pb, GetBitContext *gb)
Definition: mpeg4audio.h:132
AOT_AAC_MAIN
@ AOT_AAC_MAIN
Y Main.
Definition: mpeg4audio.h:76
AOT_LD_SURROUND
@ AOT_LD_SURROUND
N Low Delay MPEG Surround.
Definition: mpeg4audio.h:116
c
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
AOT_HVXC
@ AOT_HVXC
N Harmonic Vector eXcitation Coding.
Definition: mpeg4audio.h:84
AOT_ER_AAC_SCALABLE
@ AOT_ER_AAC_SCALABLE
N Error Resilient Scalable.
Definition: mpeg4audio.h:92
AOT_AAC_SCALABLE
@ AOT_AAC_SCALABLE
N Scalable.
Definition: mpeg4audio.h:81
AOT_DST
@ AOT_DST
N Direct Stream Transfer.
Definition: mpeg4audio.h:107
AOT_L2
@ AOT_L2
Y Layer 2.
Definition: mpeg4audio.h:105
AOT_WAVESYNTH
@ AOT_WAVESYNTH
N Wavetable Synthesis.
Definition: mpeg4audio.h:87
size
int size
Definition: twinvq_data.h:10344
AOT_ER_CELP
@ AOT_ER_CELP
N Error Resilient Code Excited Linear Prediction.
Definition: mpeg4audio.h:96
AOT_ER_HVXC
@ AOT_ER_HVXC
N Error Resilient Harmonic Vector eXcitation Coding.
Definition: mpeg4audio.h:97
offset
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf offset
Definition: writing_filters.txt:86
attributes.h
MPEG4AudioConfig::ext_object_type
int ext_object_type
Definition: mpeg4audio.h:38
MPEG4AudioConfig::channels
int channels
Definition: mpeg4audio.h:42
ff_mpeg4audio_get_config_gb
int ff_mpeg4audio_get_config_gb(MPEG4AudioConfig *c, GetBitContext *gb, int sync_extension, void *logctx)
Parse MPEG-4 systems extradata from a potentially unaligned GetBitContext to retrieve audio configura...
Definition: mpeg4audio.c:92
AOT_AAC_SSR
@ AOT_AAC_SSR
N (code in SoC repo) Scalable Sample Rate.
Definition: mpeg4audio.h:78
put_bits_count
static int put_bits_count(PutBitContext *s)
Definition: put_bits.h:80
AOT_ER_AAC_ELD
@ AOT_ER_AAC_ELD
N Error Resilient Enhanced Low Delay.
Definition: mpeg4audio.h:111
av_always_inline
#define av_always_inline
Definition: attributes.h:49
MPEG4AudioConfig::chan_config
int chan_config
Definition: mpeg4audio.h:36
AOT_NULL
@ AOT_NULL
Definition: mpeg4audio.h:74
MPEG4AudioConfig::ext_sample_rate
int ext_sample_rate
Definition: mpeg4audio.h:40
AOT_ER_BSAC
@ AOT_ER_BSAC
N Error Resilient Bit-Sliced Arithmetic Coding.
Definition: mpeg4audio.h:94
ff_mpeg4audio_channels
const uint8_t ff_mpeg4audio_channels[14]
Definition: mpeg4audio.c:60
align_get_bits
static const uint8_t * align_get_bits(GetBitContext *s)
Definition: get_bits.h:694
MPEG4AudioConfig::object_type
int object_type
Definition: mpeg4audio.h:33
MPEG4AudioConfig::ext_sampling_index
int ext_sampling_index
Definition: mpeg4audio.h:39
MPEG4AudioConfig::ps
int ps
-1 implicit, 1 presence
Definition: mpeg4audio.h:43
AOT_TWINVQ
@ AOT_TWINVQ
N Twin Vector Quantizer.
Definition: mpeg4audio.h:82
AOT_SBR
@ AOT_SBR
Y Spectral Band Replication.
Definition: mpeg4audio.h:80
AOT_SSC
@ AOT_SSC
N SinuSoidal Coding.
Definition: mpeg4audio.h:100
MPEG4AudioConfig::sbr
int sbr
-1 implicit, 1 presence
Definition: mpeg4audio.h:37
ff_mpeg4audio_sample_rates
const int ff_mpeg4audio_sample_rates[16]
Definition: mpeg4audio_sample_rates.h:26
MPEG4AudioConfig::frame_length_short
int frame_length_short
Definition: mpeg4audio.h:44
AOT_ALS
@ AOT_ALS
Y Audio LosslesS.
Definition: mpeg4audio.h:108
AOT_L3
@ AOT_L3
Y Layer 3.
Definition: mpeg4audio.h:106
put_bits.h
AOT_AAC_LC
@ AOT_AAC_LC
Y Low Complexity.
Definition: mpeg4audio.h:77
AOT_AAC_LTP
@ AOT_AAC_LTP
Y Long Term Prediction.
Definition: mpeg4audio.h:79
AOT_SAOC
@ AOT_SAOC
N Spatial Audio Object Coding.
Definition: mpeg4audio.h:115
AOT_SMR_SIMPLE
@ AOT_SMR_SIMPLE
N Symbolic Music Representation Simple.
Definition: mpeg4audio.h:112
MPEG4AudioConfig::sample_rate
int sample_rate
Definition: mpeg4audio.h:35