FFmpeg
Main Page
Related Pages
Modules
Namespaces
Data Structures
Files
Examples
File List
Globals
All
Data Structures
Namespaces
Files
Functions
Variables
Typedefs
Enumerations
Enumerator
Macros
Groups
Pages
libavcodec
atrac3plus.h
Go to the documentation of this file.
1
/*
2
* ATRAC3+ compatible decoder
3
*
4
* Copyright (c) 2010-2013 Maxim Poliakovski
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
* Global structures, constants and data for ATRAC3+ decoder.
26
*/
27
28
#ifndef AVCODEC_ATRAC3PLUS_H
29
#define AVCODEC_ATRAC3PLUS_H
30
31
#include <stdint.h>
32
33
#include "
libavutil/float_dsp.h
"
34
#include "
atrac.h
"
35
#include "
avcodec.h
"
36
#include "
fft.h
"
37
#include "
get_bits.h
"
38
39
/** Global unit sizes */
40
#define ATRAC3P_SUBBANDS 16
///< number of PQF subbands
41
#define ATRAC3P_SUBBAND_SAMPLES 128
///< number of samples per subband
42
#define ATRAC3P_FRAME_SAMPLES (ATRAC3P_SUBBAND_SAMPLES * ATRAC3P_SUBBANDS)
43
44
#define ATRAC3P_PQF_FIR_LEN 12
///< length of the prototype FIR of the PQF
45
46
/** Global constants */
47
#define ATRAC3P_POWER_COMP_OFF 15
///< disable power compensation
48
49
/** ATRAC3+ channel unit types */
50
enum
Atrac3pChannelUnitTypes
{
51
CH_UNIT_MONO
= 0,
///< unit containing one coded channel
52
CH_UNIT_STEREO
= 1,
///< unit containing two jointly-coded channels
53
CH_UNIT_EXTENSION
= 2,
///< unit containing extension information
54
CH_UNIT_TERMINATOR
= 3
///< unit sequence terminator
55
};
56
57
/** Per-channel IPQF history */
58
typedef
struct
Atrac3pIPQFChannelCtx
{
59
DECLARE_ALIGNED
(32,
float
,
buf1
)[
ATRAC3P_PQF_FIR_LEN
* 2][8];
60
DECLARE_ALIGNED
(32,
float
,
buf2
)[
ATRAC3P_PQF_FIR_LEN
* 2][8];
61
int
pos
;
62
}
Atrac3pIPQFChannelCtx
;
63
64
/** Amplitude envelope of a group of sine waves */
65
typedef
struct
Atrac3pWaveEnvelope
{
66
int
has_start_point
;
///< indicates start point within the GHA window
67
int
has_stop_point
;
///< indicates stop point within the GHA window
68
int
start_pos
;
///< start position expressed in n*4 samples
69
int
stop_pos
;
///< stop position expressed in n*4 samples
70
}
Atrac3pWaveEnvelope
;
71
72
/** Parameters of a group of sine waves */
73
typedef
struct
Atrac3pWavesData
{
74
Atrac3pWaveEnvelope
pend_env
;
///< pending envelope from the previous frame
75
Atrac3pWaveEnvelope
curr_env
;
///< group envelope from the current frame
76
int
num_wavs
;
///< number of sine waves in the group
77
int
start_index
;
///< start index into global tones table for that subband
78
}
Atrac3pWavesData
;
79
80
/** Parameters of a single sine wave */
81
typedef
struct
Atrac3pWaveParam
{
82
int
freq_index
;
///< wave frequency index
83
int
amp_sf
;
///< quantized amplitude scale factor
84
int
amp_index
;
///< quantized amplitude index
85
int
phase_index
;
///< quantized phase index
86
}
Atrac3pWaveParam
;
87
88
/** Sound channel parameters */
89
typedef
struct
Atrac3pChanParams
{
90
int
ch_num
;
91
int
num_coded_vals
;
///< number of transmitted quant unit values
92
int
fill_mode
;
93
int
split_point
;
94
int
table_type
;
///< table type: 0 - tone?, 1- noise?
95
int
qu_wordlen
[32];
///< array of word lengths for each quant unit
96
int
qu_sf_idx
[32];
///< array of scale factor indexes for each quant unit
97
int
qu_tab_idx
[32];
///< array of code table indexes for each quant unit
98
int16_t
spectrum
[2048];
///< decoded IMDCT spectrum
99
uint8_t
power_levs
[5];
///< power compensation levels
100
101
/* imdct window shape history (2 frames) for overlapping. */
102
uint8_t
wnd_shape_hist
[2][
ATRAC3P_SUBBANDS
];
///< IMDCT window shape, 0=sine/1=steep
103
uint8_t
*
wnd_shape
;
///< IMDCT window shape for current frame
104
uint8_t
*
wnd_shape_prev
;
///< IMDCT window shape for previous frame
105
106
/* gain control data history (2 frames) for overlapping. */
107
AtracGainInfo
gain_data_hist
[2][
ATRAC3P_SUBBANDS
];
///< gain control data for all subbands
108
AtracGainInfo
*
gain_data
;
///< gain control data for next frame
109
AtracGainInfo
*
gain_data_prev
;
///< gain control data for previous frame
110
int
num_gain_subbands
;
///< number of subbands with gain control data
111
112
/* tones data history (2 frames) for overlapping. */
113
Atrac3pWavesData
tones_info_hist
[2][
ATRAC3P_SUBBANDS
];
114
Atrac3pWavesData
*
tones_info
;
115
Atrac3pWavesData
*
tones_info_prev
;
116
}
Atrac3pChanParams
;
117
118
/* Per-unit sine wave parameters */
119
typedef
struct
Atrac3pWaveSynthParams
{
120
int
tones_present
;
///< 1 - tones info present
121
int
amplitude_mode
;
///< 1 - low range, 0 - high range
122
int
num_tone_bands
;
///< number of PQF bands with tones
123
uint8_t
tone_sharing
[
ATRAC3P_SUBBANDS
];
///< 1 - subband-wise tone sharing flags
124
uint8_t
tone_master
[
ATRAC3P_SUBBANDS
];
///< 1 - subband-wise tone channel swapping
125
uint8_t
phase_shift
[
ATRAC3P_SUBBANDS
];
///< 1 - subband-wise 180° phase shifting
126
int
tones_index
;
///< total sum of tones in this unit
127
Atrac3pWaveParam
waves
[48];
128
}
Atrac3pWaveSynthParams
;
129
130
/** Channel unit parameters */
131
typedef
struct
Atrac3pChanUnitCtx
{
132
/* channel unit variables */
133
int
unit_type
;
///< unit type (mono/stereo)
134
int
num_quant_units
;
135
int
num_subbands
;
136
int
used_quant_units
;
///< number of quant units with coded spectrum
137
int
num_coded_subbands
;
///< number of subbands with coded spectrum
138
int
mute_flag
;
///< mute flag
139
int
use_full_table
;
///< 1 - full table list, 0 - restricted one
140
int
noise_present
;
///< 1 - global noise info present
141
int
noise_level_index
;
///< global noise level index
142
int
noise_table_index
;
///< global noise RNG table index
143
uint8_t
swap_channels
[
ATRAC3P_SUBBANDS
];
///< 1 - perform subband-wise channel swapping
144
uint8_t
negate_coeffs
[
ATRAC3P_SUBBANDS
];
///< 1 - subband-wise IMDCT coefficients negation
145
Atrac3pChanParams
channels
[2];
146
147
/* Variables related to GHA tones */
148
Atrac3pWaveSynthParams
wave_synth_hist
[2];
///< waves synth history for two frames
149
Atrac3pWaveSynthParams
*
waves_info
;
150
Atrac3pWaveSynthParams
*
waves_info_prev
;
151
152
Atrac3pIPQFChannelCtx
ipqf_ctx
[2];
153
DECLARE_ALIGNED
(32,
float
,
prev_buf
)[2][
ATRAC3P_FRAME_SAMPLES
];
///< overlapping buffer
154
}
Atrac3pChanUnitCtx
;
155
156
/**
157
* Initialize VLC tables for bitstream parsing.
158
*/
159
void
ff_atrac3p_init_vlcs
(
void
);
160
161
/**
162
* Decode bitstream data of a channel unit.
163
*
164
* @param[in] gb the GetBit context
165
* @param[in,out] ctx ptr to the channel unit context
166
* @param[in] num_channels number of channels to process
167
* @param[in] avctx ptr to the AVCodecContext
168
* @return result code: 0 = OK, otherwise - error code
169
*/
170
int
ff_atrac3p_decode_channel_unit
(
GetBitContext
*gb,
Atrac3pChanUnitCtx
*ctx,
171
int
num_channels,
AVCodecContext
*avctx);
172
173
/**
174
* Initialize IMDCT transform.
175
*
176
* @param[in] avctx ptr to the AVCodecContext
177
* @param[in] mdct_ctx pointer to MDCT transform context
178
*/
179
void
ff_atrac3p_init_imdct
(
AVCodecContext
*avctx,
FFTContext
*mdct_ctx);
180
181
/**
182
* Initialize sine waves synthesizer.
183
*/
184
void
ff_atrac3p_init_wave_synth
(
void
);
185
186
/**
187
* Synthesize sine waves for a particular subband.
188
*
189
* @param[in] ch_unit pointer to the channel unit context
190
* @param[in] fdsp pointer to float DSP context
191
* @param[in] ch_num which channel to process
192
* @param[in] sb which subband to process
193
* @param[out] out receives processed data
194
*/
195
void
ff_atrac3p_generate_tones
(
Atrac3pChanUnitCtx
*ch_unit,
AVFloatDSPContext
*fdsp,
196
int
ch_num,
int
sb,
float
*
out
);
197
198
/**
199
* Perform power compensation aka noise dithering.
200
*
201
* @param[in] ctx ptr to the channel context
202
* @param[in] ch_index which channel to process
203
* @param[in,out] sp ptr to channel spectrum to process
204
* @param[in] rng_index indicates which RNG table to use
205
* @param[in] sb_num which subband to process
206
*/
207
void
ff_atrac3p_power_compensation
(
Atrac3pChanUnitCtx
*ctx,
int
ch_index,
208
float
*
sp
,
int
rng_index,
int
sb_num);
209
210
/**
211
* Regular IMDCT and windowing without overlapping,
212
* with spectrum reversal in the odd subbands.
213
*
214
* @param[in] fdsp pointer to float DSP context
215
* @param[in] mdct_ctx pointer to MDCT transform context
216
* @param[in] pIn float input
217
* @param[out] pOut float output
218
* @param[in] wind_id which MDCT window to apply
219
* @param[in] sb subband number
220
*/
221
void
ff_atrac3p_imdct
(
AVFloatDSPContext
*fdsp,
FFTContext
*mdct_ctx,
float
*pIn,
222
float
*pOut,
int
wind_id,
int
sb);
223
224
/**
225
* Subband synthesis filter based on the polyphase quadrature (pseudo-QMF)
226
* filter bank.
227
*
228
* @param[in] dct_ctx ptr to the pre-initialized IDCT context
229
* @param[in,out] hist ptr to the filter history
230
* @param[in] in input data to process
231
* @param[out] out receives processed data
232
*/
233
void
ff_atrac3p_ipqf
(
FFTContext
*dct_ctx,
Atrac3pIPQFChannelCtx
*hist,
234
const
float
*
in
,
float
*
out
);
235
236
extern
const
uint16_t
ff_atrac3p_qu_to_spec_pos
[33];
237
extern
const
float
ff_atrac3p_sf_tab
[64];
238
extern
const
float
ff_atrac3p_mant_tab
[8];
239
240
#endif
/* AVCODEC_ATRAC3PLUS_H */
Generated on Sun Mar 8 2015 02:34:48 for FFmpeg by
1.8.2