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 )
6 * This file is part of FFmpeg.
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.
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.
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
25 * AAC definitions and structures
26 * @author Oded Shimon ( ods15 ods15 dyndns org )
27 * @author Maxim Gavrilov ( maxim.gavrilov gmail com )
35 #include "mpeg4audio.h"
39 #define AAC_INIT_VLC_STATIC(num, size) \
40 INIT_VLC_STATIC(&vlc_spectral[num], 6, ff_aac_spectral_sizes[num], \
41 ff_aac_spectral_bits[num], sizeof( ff_aac_spectral_bits[num][0]), sizeof( ff_aac_spectral_bits[num][0]), \
42 ff_aac_spectral_codes[num], sizeof(ff_aac_spectral_codes[num][0]), sizeof(ff_aac_spectral_codes[num][0]), \
45 #define MAX_CHANNELS 64
46 #define MAX_ELEM_ID 16
48 #define TNS_MAX_ORDER 20
49 #define PNS_MEAN_ENERGY 3719550720.0f // sqrt(3.0) * 1<<31
51 enum AudioObjectType
{
54 AOT_AAC_MAIN
, ///< Y Main
55 AOT_AAC_LC
, ///< Y Low Complexity
56 AOT_AAC_SSR
, ///< N (code in SoC repo) Scalable Sample Rate
57 AOT_AAC_LTP
, ///< N (code in SoC repo) Long Term Prediction
58 AOT_SBR
, ///< N (in progress) Spectral Band Replication
59 AOT_AAC_SCALABLE
, ///< N Scalable
60 AOT_TWINVQ
, ///< N Twin Vector Quantizer
61 AOT_CELP
, ///< N Code Excited Linear Prediction
62 AOT_HVXC
, ///< N Harmonic Vector eXcitation Coding
63 AOT_TTSI
= 12, ///< N Text-To-Speech Interface
64 AOT_MAINSYNTH
, ///< N Main Synthesis
65 AOT_WAVESYNTH
, ///< N Wavetable Synthesis
66 AOT_MIDI
, ///< N General MIDI
67 AOT_SAFX
, ///< N Algorithmic Synthesis and Audio Effects
68 AOT_ER_AAC_LC
, ///< N Error Resilient Low Complexity
69 AOT_ER_AAC_LTP
= 19, ///< N Error Resilient Long Term Prediction
70 AOT_ER_AAC_SCALABLE
, ///< N Error Resilient Scalable
71 AOT_ER_TWINVQ
, ///< N Error Resilient Twin Vector Quantizer
72 AOT_ER_BSAC
, ///< N Error Resilient Bit-Sliced Arithmetic Coding
73 AOT_ER_AAC_LD
, ///< N Error Resilient Low Delay
74 AOT_ER_CELP
, ///< N Error Resilient Code Excited Linear Prediction
75 AOT_ER_HVXC
, ///< N Error Resilient Harmonic Vector eXcitation Coding
76 AOT_ER_HILN
, ///< N Error Resilient Harmonic and Individual Lines plus Noise
77 AOT_ER_PARAM
, ///< N Error Resilient Parametric
78 AOT_SSC
, ///< N SinuSoidal Coding
81 enum RawDataBlockType
{
92 enum ExtensionPayloadID
{
96 EXT_DYNAMIC_RANGE
= 0xb,
98 EXT_SBR_DATA_CRC
= 0xe,
101 enum WindowSequence
{
104 EIGHT_SHORT_SEQUENCE
,
109 ZERO_BT
= 0, ///< Scalefactors and spectral data are all zero.
110 FIRST_PAIR_BT
= 5, ///< This and later band types encode two values (rather than four) with one code word.
111 ESC_BT
= 11, ///< Spectral data are coded with an escape sequence.
112 NOISE_BT
= 13, ///< Spectral data are scaled white noise not coded in the bitstream.
113 INTENSITY_BT2
= 14, ///< Scalefactor data are intensity stereo positions.
114 INTENSITY_BT
= 15, ///< Scalefactor data are intensity stereo positions.
117 #define IS_CODEBOOK_UNSIGNED(x) ((x - 1) & 10)
119 enum ChannelPosition
{
120 AAC_CHANNEL_FRONT
= 1,
121 AAC_CHANNEL_SIDE
= 2,
122 AAC_CHANNEL_BACK
= 3,
128 * The point during decoding at which channel coupling is applied.
132 BETWEEN_TNS_AND_IMDCT
,
137 * Individual Channel Stream
140 uint8_t max_sfb
; ///< number of scalefactor bands per group
141 enum WindowSequence window_sequence
[2];
142 uint8_t use_kb_window
[2]; ///< If set, use Kaiser-Bessel window, otherwise use a sinus window.
143 int num_window_groups
;
144 uint8_t group_len
[8];
145 const uint16_t *swb_offset
; ///< table of offsets to the lowest spectral coefficient of a scalefactor band, sfb, for a particular window
146 int num_swb
; ///< number of scalefactor window bands
149 } IndividualChannelStream
;
152 * Temporal Noise Shaping
160 float coef
[8][4][TNS_MAX_ORDER
];
161 } TemporalNoiseShaping
;
164 * Dynamic Range Control - decoded from the bitstream but not processed further.
167 int pce_instance_tag
; ///< Indicates with which program the DRC info is associated.
168 int dyn_rng_sgn
[17]; ///< DRC sign information; 0 - positive, 1 - negative
169 int dyn_rng_ctl
[17]; ///< DRC magnitude information
170 int exclude_mask
[MAX_CHANNELS
]; ///< Channels to be excluded from DRC processing.
171 int band_incr
; ///< Number of DRC bands greater than 1 having DRC info.
172 int interpolation_scheme
; ///< Indicates the interpolation scheme used in the SBR QMF domain.
173 int band_top
[17]; ///< Indicates the top of the i-th DRC band in units of 4 spectral lines.
174 int prog_ref_level
; /**< A reference level for the long-term program audio level for all
177 } DynamicRangeControl
;
186 * coupling parameters
189 enum CouplingPoint coupling_point
; ///< The point during decoding at which coupling is applied.
190 int num_coupled
; ///< number of target elements
191 enum RawDataBlockType type
[8]; ///< Type of channel element to be coupled - SCE or CPE.
192 int id_select
[8]; ///< element id
193 int ch_select
[8]; /**< [0] shared list of gains; [1] list of gains for right channel;
194 * [2] list of gains for left channel; [3] lists of gains for both channels
200 * Single Channel Element - used for both SCE and LFE elements.
203 IndividualChannelStream ics
;
204 TemporalNoiseShaping tns
;
205 enum BandType band_type
[120]; ///< band types
206 int band_type_run_end
[120]; ///< band type run end points
207 float sf
[120]; ///< scalefactors
208 DECLARE_ALIGNED_16(float, coeffs
[1024]); ///< coefficients for IMDCT
209 DECLARE_ALIGNED_16(float, saved
[512]); ///< overlap
210 DECLARE_ALIGNED_16(float, ret
[1024]); ///< PCM output
211 } SingleChannelElement
;
214 * channel element - generic struct for SCE/CPE/CCE/LFE
218 uint8_t ms_mask
[120]; ///< Set if mid/side stereo is used for each scalefactor window band
220 SingleChannelElement ch
[2];
222 ChannelCoupling coup
;
229 AVCodecContext
* avccontext
;
231 MPEG4AudioConfig m4ac
;
233 int is_saved
; ///< Set if elements have stored overlap from previous frame.
234 DynamicRangeControl che_drc
;
240 enum ChannelPosition che_pos
[4][MAX_ELEM_ID
]; /**< channel element channel mapping with the
241 * first index as the first 4 raw data block types
243 ChannelElement
* che
[4][MAX_ELEM_ID
];
247 * @defgroup temporary aligned temporary buffers (We do not want to have these on the stack.)
250 DECLARE_ALIGNED_16(float, buf_mdct
[1024]);
254 * @defgroup tables Computed / set up during initialization.
258 MDCTContext mdct_small
;
264 * @defgroup output Members used for output interleaving.
267 float *output_data
[MAX_CHANNELS
]; ///< Points to each element's 'ret' buffer (PCM output).
268 float add_bias
; ///< offset for dsp.float_to_int16
269 float sf_scale
; ///< Pre-scale for correct IMDCT and dsp.float_to_int16.
270 int sf_offset
; ///< offset into pow2sf_tab as appropriate for dsp.float_to_int16
275 #endif /* AVCODEC_AAC_H */