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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 {
34     int object_type;
35     int sampling_index;
36     int sample_rate;
37     int chan_config;
38     int sbr; ///< -1 implicit, 1 presence
39     int ext_object_type;
40     int ext_sampling_index;
41     int ext_sample_rate;
42     int ext_chan_config;
43     int channels;
44     int ps;  ///< -1 implicit, 1 presence
45     int frame_length_short;
46 } MPEG4AudioConfig;
47 
48 extern av_export_avcodec const int avpriv_mpeg4audio_sample_rates[16];
49 extern const uint8_t ff_mpeg4audio_channels[14];
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  */
59 int ff_mpeg4audio_get_config_gb(MPEG4AudioConfig *c, GetBitContext *gb,
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  */
71 int avpriv_mpeg4audio_get_config(MPEG4AudioConfig *c, const uint8_t *buf,
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  */
84 int avpriv_mpeg4audio_get_config2(MPEG4AudioConfig *c, const uint8_t *buf,
85                                   int size, int sync_extension, void *logctx);
86 
87 enum AudioObjectType {
88     AOT_NULL,
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 
ff_pce_copy_bits(PutBitContext * pb,GetBitContext * gb,int bits)137 static av_always_inline unsigned int ff_pce_copy_bits(PutBitContext *pb,
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 
ff_copy_pce_data(PutBitContext * pb,GetBitContext * gb)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);
168     align_put_bits(pb);
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 */
178