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 "internal.h"
31 #include "put_bits.h"
32 
33 typedef struct MPEG4AudioConfig {
38  int sbr; ///< -1 implicit, 1 presence
43  int channels;
44  int ps; ///< -1 implicit, 1 presence
47 
49 extern const uint8_t ff_mpeg4audio_channels[8];
50 
51 /**
52  * Parse MPEG-4 systems extradata from a potentially unaligned GetBitContext to retrieve audio configuration.
53  * @param[in] c MPEG4AudioConfig structure to fill.
54  * @param[in] gb Extradata from container.
55  * @param[in] sync_extension look for a sync extension after config if true.
56  * @param[in] logctx opaque struct starting with an AVClass element, used for logging.
57  * @return negative AVERROR code on error, on success AudioSpecificConfig bit index in extradata.
58  */
60  int sync_extension, void *logctx);
61 
62 #if LIBAVCODEC_VERSION_MAJOR < 59
63 /**
64  * Parse MPEG-4 systems extradata from a raw buffer to retrieve audio configuration.
65  * @param[in] c MPEG4AudioConfig structure to fill.
66  * @param[in] buf Extradata from container.
67  * @param[in] bit_size Extradata size in bits.
68  * @param[in] sync_extension look for a sync extension after config if true.
69  * @return negative AVERROR code on error, on success AudioSpecificConfig bit index in extradata.
70  */
72  int bit_size, int sync_extension);
73 #endif
74 
75 /**
76  * Parse MPEG-4 systems extradata from a raw buffer to retrieve audio configuration.
77  * @param[in] c MPEG4AudioConfig structure to fill.
78  * @param[in] buf Extradata from container.
79  * @param[in] size Extradata size in bytes.
80  * @param[in] sync_extension look for a sync extension after config if true.
81  * @param[in] logctx opaque struct starting with an AVClass element, used for logging.
82  * @return negative AVERROR code on error, AudioSpecificConfig bit index in extradata on success.
83  */
85  int size, int sync_extension, void *logctx);
86 
89  // Support? Name
90  AOT_AAC_MAIN, ///< Y Main
91  AOT_AAC_LC, ///< Y Low Complexity
92  AOT_AAC_SSR, ///< N (code in SoC repo) Scalable Sample Rate
93  AOT_AAC_LTP, ///< Y Long Term Prediction
94  AOT_SBR, ///< Y Spectral Band Replication
95  AOT_AAC_SCALABLE, ///< N Scalable
96  AOT_TWINVQ, ///< N Twin Vector Quantizer
97  AOT_CELP, ///< N Code Excited Linear Prediction
98  AOT_HVXC, ///< N Harmonic Vector eXcitation Coding
99  AOT_TTSI = 12, ///< N Text-To-Speech Interface
100  AOT_MAINSYNTH, ///< N Main Synthesis
101  AOT_WAVESYNTH, ///< N Wavetable Synthesis
102  AOT_MIDI, ///< N General MIDI
103  AOT_SAFX, ///< N Algorithmic Synthesis and Audio Effects
104  AOT_ER_AAC_LC, ///< N Error Resilient Low Complexity
105  AOT_ER_AAC_LTP = 19, ///< N Error Resilient Long Term Prediction
106  AOT_ER_AAC_SCALABLE, ///< N Error Resilient Scalable
107  AOT_ER_TWINVQ, ///< N Error Resilient Twin Vector Quantizer
108  AOT_ER_BSAC, ///< N Error Resilient Bit-Sliced Arithmetic Coding
109  AOT_ER_AAC_LD, ///< N Error Resilient Low Delay
110  AOT_ER_CELP, ///< N Error Resilient Code Excited Linear Prediction
111  AOT_ER_HVXC, ///< N Error Resilient Harmonic Vector eXcitation Coding
112  AOT_ER_HILN, ///< N Error Resilient Harmonic and Individual Lines plus Noise
113  AOT_ER_PARAM, ///< N Error Resilient Parametric
114  AOT_SSC, ///< N SinuSoidal Coding
115  AOT_PS, ///< N Parametric Stereo
116  AOT_SURROUND, ///< N MPEG Surround
117  AOT_ESCAPE, ///< Y Escape Value
118  AOT_L1, ///< Y Layer 1
119  AOT_L2, ///< Y Layer 2
120  AOT_L3, ///< Y Layer 3
121  AOT_DST, ///< N Direct Stream Transfer
122  AOT_ALS, ///< Y Audio LosslesS
123  AOT_SLS, ///< N Scalable LosslesS
124  AOT_SLS_NON_CORE, ///< N Scalable LosslesS (non core)
125  AOT_ER_AAC_ELD, ///< N Error Resilient Enhanced Low Delay
126  AOT_SMR_SIMPLE, ///< N Symbolic Music Representation Simple
127  AOT_SMR_MAIN, ///< N Symbolic Music Representation Main
128  AOT_USAC_NOSBR, ///< N Unified Speech and Audio Coding (no SBR)
129  AOT_SAOC, ///< N Spatial Audio Object Coding
130  AOT_LD_SURROUND, ///< N Low Delay MPEG Surround
131  AOT_USAC, ///< N Unified Speech and Audio Coding
132 };
133 
134 #define MAX_PCE_SIZE 320 ///<Maximum size of a PCE including the 3-bit ID_PCE
135  ///<marker and the comment
136 
138  GetBitContext *gb,
139  int bits)
140 {
141  unsigned int el = get_bits(gb, bits);
142  put_bits(pb, bits, el);
143  return el;
144 }
145 
146 static inline int ff_copy_pce_data(PutBitContext *pb, GetBitContext *gb)
147 {
148  int five_bit_ch, four_bit_ch, comment_size, bits;
149  int offset = put_bits_count(pb);
150 
151  ff_pce_copy_bits(pb, gb, 10); // Tag, Object Type, Frequency
152  five_bit_ch = ff_pce_copy_bits(pb, gb, 4); // Front
153  five_bit_ch += ff_pce_copy_bits(pb, gb, 4); // Side
154  five_bit_ch += ff_pce_copy_bits(pb, gb, 4); // Back
155  four_bit_ch = ff_pce_copy_bits(pb, gb, 2); // LFE
156  four_bit_ch += ff_pce_copy_bits(pb, gb, 3); // Data
157  five_bit_ch += ff_pce_copy_bits(pb, gb, 4); // Coupling
158  if (ff_pce_copy_bits(pb, gb, 1)) // Mono Mixdown
159  ff_pce_copy_bits(pb, gb, 4);
160  if (ff_pce_copy_bits(pb, gb, 1)) // Stereo Mixdown
161  ff_pce_copy_bits(pb, gb, 4);
162  if (ff_pce_copy_bits(pb, gb, 1)) // Matrix Mixdown
163  ff_pce_copy_bits(pb, gb, 3);
164  for (bits = five_bit_ch*5+four_bit_ch*4; bits > 16; bits -= 16)
165  ff_pce_copy_bits(pb, gb, 16);
166  if (bits)
167  ff_pce_copy_bits(pb, gb, bits);
169  align_get_bits(gb);
170  comment_size = ff_pce_copy_bits(pb, gb, 8);
171  for (; comment_size > 0; comment_size--)
172  ff_pce_copy_bits(pb, gb, 8);
173 
174  return put_bits_count(pb) - offset;
175 }
176 
177 #endif /* AVCODEC_MPEG4AUDIO_H */
N Parametric Stereo.
Definition: mpeg4audio.h:115
Y Layer 1.
Definition: mpeg4audio.h:118
static void put_bits(Jpeg2000EncoderContext *s, int val, int n)
put n times val bit
Definition: j2kenc.c:208
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:379
void avpriv_align_put_bits(PutBitContext *s)
Pad the bitstream with zeros up to the next byte boundary.
Definition: bitstream.c:48
static av_always_inline unsigned int ff_pce_copy_bits(PutBitContext *pb, GetBitContext *gb, int bits)
Definition: mpeg4audio.h:137
int avpriv_mpeg4audio_get_config(MPEG4AudioConfig *c, const uint8_t *buf, int bit_size, int sync_extension)
Parse MPEG-4 systems extradata from a raw buffer to retrieve audio configuration. ...
Definition: mpeg4audio.c:160
Macro definitions for various function/variable attributes.
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:177
const uint8_t ff_mpeg4audio_channels[8]
Definition: mpeg4audio.c:67
N Scalable LosslesS (non core)
Definition: mpeg4audio.h:124
N Code Excited Linear Prediction.
Definition: mpeg4audio.h:97
N Error Resilient Parametric.
Definition: mpeg4audio.h:113
N Error Resilient Long Term Prediction.
Definition: mpeg4audio.h:105
N MPEG Surround.
Definition: mpeg4audio.h:116
uint8_t
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
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
N Error Resilient Low Delay.
Definition: mpeg4audio.h:109
N Algorithmic Synthesis and Audio Effects.
Definition: mpeg4audio.h:103
N Scalable LosslesS.
Definition: mpeg4audio.h:123
N General MIDI.
Definition: mpeg4audio.h:102
N Error Resilient Harmonic and Individual Lines plus Noise.
Definition: mpeg4audio.h:112
bitstream reader API header.
Y Escape Value.
Definition: mpeg4audio.h:117
ptrdiff_t size
Definition: opengl_enc.c:100
N Error Resilient Low Complexity.
Definition: mpeg4audio.h:104
N Unified Speech and Audio Coding (no SBR)
Definition: mpeg4audio.h:128
N Symbolic Music Representation Main.
Definition: mpeg4audio.h:127
#define av_export_avcodec
Definition: internal.h:431
N Error Resilient Twin Vector Quantizer.
Definition: mpeg4audio.h:107
uint8_t bits
Definition: vp3data.h:202
N Text-To-Speech Interface.
Definition: mpeg4audio.h:99
N Low Delay MPEG Surround.
Definition: mpeg4audio.h:130
av_export_avcodec const int avpriv_mpeg4audio_sample_rates[16]
Definition: mpeg4audio.c:62
static int put_bits_count(PutBitContext *s)
Definition: put_bits.h:85
N Error Resilient Scalable.
Definition: mpeg4audio.h:106
AudioObjectType
Definition: mpeg4audio.h:87
N Unified Speech and Audio Coding.
Definition: mpeg4audio.h:131
N Harmonic Vector eXcitation Coding.
Definition: mpeg4audio.h:98
N Error Resilient Harmonic Vector eXcitation Coding.
Definition: mpeg4audio.h:111
Y Main.
Definition: mpeg4audio.h:90
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:86
N Main Synthesis.
Definition: mpeg4audio.h:100
N (code in SoC repo) Scalable Sample Rate.
Definition: mpeg4audio.h:92
N Scalable.
Definition: mpeg4audio.h:95
N Direct Stream Transfer.
Definition: mpeg4audio.h:121
N Wavetable Synthesis.
Definition: mpeg4audio.h:101
N Error Resilient Code Excited Linear Prediction.
Definition: mpeg4audio.h:110
Y Layer 2.
Definition: mpeg4audio.h:119
void * buf
Definition: avisynth_c.h:766
static int ff_copy_pce_data(PutBitContext *pb, GetBitContext *gb)
Definition: mpeg4audio.h:146
N Error Resilient Bit-Sliced Arithmetic Coding.
Definition: mpeg4audio.h:108
int frame_length_short
Definition: mpeg4audio.h:45
N Error Resilient Enhanced Low Delay.
Definition: mpeg4audio.h:125
N Twin Vector Quantizer.
Definition: mpeg4audio.h:96
Y Spectral Band Replication.
Definition: mpeg4audio.h:94
common internal api header.
N SinuSoidal Coding.
Definition: mpeg4audio.h:114
Y Audio LosslesS.
Definition: mpeg4audio.h:122
Y Layer 3.
Definition: mpeg4audio.h:120
Y Long Term Prediction.
Definition: mpeg4audio.h:93
static const uint8_t * align_get_bits(GetBitContext *s)
Definition: get_bits.h:693
N Symbolic Music Representation Simple.
Definition: mpeg4audio.h:126
int sbr
-1 implicit, 1 presence
Definition: mpeg4audio.h:38
#define av_always_inline
Definition: attributes.h:39
int ext_sampling_index
Definition: mpeg4audio.h:40
int ps
-1 implicit, 1 presence
Definition: mpeg4audio.h:44
N Spatial Audio Object Coding.
Definition: mpeg4audio.h:129
Y Low Complexity.
Definition: mpeg4audio.h:91
bitstream writer API