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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 "libavutil/mem_internal.h"
35 
36 #include "atrac.h"
37 #include "avcodec.h"
38 #include "fft.h"
39 #include "get_bits.h"
40 
41 /** Global unit sizes */
42 #define ATRAC3P_SUBBANDS        16  ///< number of PQF subbands
43 #define ATRAC3P_SUBBAND_SAMPLES 128 ///< number of samples per subband
44 #define ATRAC3P_FRAME_SAMPLES   (ATRAC3P_SUBBAND_SAMPLES * ATRAC3P_SUBBANDS)
45 
46 #define ATRAC3P_PQF_FIR_LEN     12  ///< length of the prototype FIR of the PQF
47 
48 /** Global constants */
49 #define ATRAC3P_POWER_COMP_OFF  15  ///< disable power compensation
50 
51 /** ATRAC3+ channel unit types */
52 enum Atrac3pChannelUnitTypes {
53     CH_UNIT_MONO       = 0, ///< unit containing one coded channel
54     CH_UNIT_STEREO     = 1, ///< unit containing two jointly-coded channels
55     CH_UNIT_EXTENSION  = 2, ///< unit containing extension information
56     CH_UNIT_TERMINATOR = 3  ///< unit sequence terminator
57 };
58 
59 /** Per-channel IPQF history */
60 typedef struct Atrac3pIPQFChannelCtx {
61     DECLARE_ALIGNED(32, float, buf1)[ATRAC3P_PQF_FIR_LEN * 2][8];
62     DECLARE_ALIGNED(32, float, buf2)[ATRAC3P_PQF_FIR_LEN * 2][8];
63     int pos;
64 } Atrac3pIPQFChannelCtx;
65 
66 /** Amplitude envelope of a group of sine waves */
67 typedef struct Atrac3pWaveEnvelope {
68     int has_start_point;    ///< indicates start point within the GHA window
69     int has_stop_point;     ///< indicates stop point within the GHA window
70     int start_pos;          ///< start position expressed in n*4 samples
71     int stop_pos;           ///< stop  position expressed in n*4 samples
72 } Atrac3pWaveEnvelope;
73 
74 /** Parameters of a group of sine waves */
75 typedef struct Atrac3pWavesData {
76     Atrac3pWaveEnvelope pend_env;   ///< pending envelope from the previous frame
77     Atrac3pWaveEnvelope curr_env;   ///< group envelope from the current frame
78     int num_wavs;           ///< number of sine waves in the group
79     int start_index;        ///< start index into global tones table for that subband
80 } Atrac3pWavesData;
81 
82 /** Parameters of a single sine wave */
83 typedef struct Atrac3pWaveParam {
84     int   freq_index;   ///< wave frequency index
85     int   amp_sf;       ///< quantized amplitude scale factor
86     int   amp_index;    ///< quantized amplitude index
87     int   phase_index;  ///< quantized phase index
88 } Atrac3pWaveParam;
89 
90 /** Sound channel parameters */
91 typedef struct Atrac3pChanParams {
92     int ch_num;
93     int num_coded_vals;         ///< number of transmitted quant unit values
94     int fill_mode;
95     int split_point;
96     int table_type;             ///< table type: 0 - tone?, 1- noise?
97     int qu_wordlen[32];         ///< array of word lengths for each quant unit
98     int qu_sf_idx[32];          ///< array of scale factor indexes for each quant unit
99     int qu_tab_idx[32];         ///< array of code table indexes for each quant unit
100     int16_t spectrum[2048];     ///< decoded IMDCT spectrum
101     uint8_t power_levs[5];      ///< power compensation levels
102 
103     /* imdct window shape history (2 frames) for overlapping. */
104     uint8_t wnd_shape_hist[2][ATRAC3P_SUBBANDS];    ///< IMDCT window shape, 0=sine/1=steep
105     uint8_t *wnd_shape;         ///< IMDCT window shape for current frame
106     uint8_t *wnd_shape_prev;    ///< IMDCT window shape for previous frame
107 
108     /* gain control data history (2 frames) for overlapping. */
109     AtracGainInfo gain_data_hist[2][ATRAC3P_SUBBANDS];  ///< gain control data for all subbands
110     AtracGainInfo *gain_data;       ///< gain control data for next frame
111     AtracGainInfo *gain_data_prev;  ///< gain control data for previous frame
112     int num_gain_subbands;      ///< number of subbands with gain control data
113 
114     /* tones data history (2 frames) for overlapping. */
115     Atrac3pWavesData tones_info_hist[2][ATRAC3P_SUBBANDS];
116     Atrac3pWavesData *tones_info;
117     Atrac3pWavesData *tones_info_prev;
118 } Atrac3pChanParams;
119 
120 /* Per-unit sine wave parameters */
121 typedef struct Atrac3pWaveSynthParams {
122     int tones_present;                      ///< 1 - tones info present
123     int amplitude_mode;                     ///< 1 - low range, 0 - high range
124     int num_tone_bands;                     ///< number of PQF bands with tones
125     uint8_t tone_sharing[ATRAC3P_SUBBANDS]; ///< 1 - subband-wise tone sharing flags
126     uint8_t tone_master[ATRAC3P_SUBBANDS];  ///< 1 - subband-wise tone channel swapping
127     uint8_t invert_phase[ATRAC3P_SUBBANDS]; ///< 1 - subband-wise phase inversion
128     int tones_index;                        ///< total sum of tones in this unit
129     Atrac3pWaveParam waves[48];
130 } Atrac3pWaveSynthParams;
131 
132 /** Channel unit parameters */
133 typedef struct Atrac3pChanUnitCtx {
134     /* channel unit variables */
135     int unit_type;                          ///< unit type (mono/stereo)
136     int num_quant_units;
137     int num_subbands;
138     int used_quant_units;                   ///< number of quant units with coded spectrum
139     int num_coded_subbands;                 ///< number of subbands with coded spectrum
140     int mute_flag;                          ///< mute flag
141     int use_full_table;                     ///< 1 - full table list, 0 - restricted one
142     int noise_present;                      ///< 1 - global noise info present
143     int noise_level_index;                  ///< global noise level index
144     int noise_table_index;                  ///< global noise RNG table index
145     uint8_t swap_channels[ATRAC3P_SUBBANDS];    ///< 1 - perform subband-wise channel swapping
146     uint8_t negate_coeffs[ATRAC3P_SUBBANDS];    ///< 1 - subband-wise IMDCT coefficients negation
147     Atrac3pChanParams channels[2];
148 
149     /* Variables related to GHA tones */
150     Atrac3pWaveSynthParams wave_synth_hist[2];     ///< waves synth history for two frames
151     Atrac3pWaveSynthParams *waves_info;
152     Atrac3pWaveSynthParams *waves_info_prev;
153 
154     Atrac3pIPQFChannelCtx ipqf_ctx[2];
155     DECLARE_ALIGNED(32, float, prev_buf)[2][ATRAC3P_FRAME_SAMPLES]; ///< overlapping buffer
156 } Atrac3pChanUnitCtx;
157 
158 /**
159  * Initialize VLC tables for bitstream parsing.
160  */
161 void ff_atrac3p_init_vlcs(void);
162 
163 /**
164  * Decode bitstream data of a channel unit.
165  *
166  * @param[in]     gb            the GetBit context
167  * @param[in,out] ctx           ptr to the channel unit context
168  * @param[in]     num_channels  number of channels to process
169  * @param[in]     avctx         ptr to the AVCodecContext
170  * @return result code: 0 = OK, otherwise - error code
171  */
172 int ff_atrac3p_decode_channel_unit(GetBitContext *gb, Atrac3pChanUnitCtx *ctx,
173                                    int num_channels, AVCodecContext *avctx);
174 
175 /**
176  * Initialize IMDCT transform.
177  *
178  * @param[in]   avctx      ptr to the AVCodecContext
179  * @param[in]   mdct_ctx   pointer to MDCT transform context
180  */
181 void ff_atrac3p_init_imdct(AVCodecContext *avctx, FFTContext *mdct_ctx);
182 
183 /**
184  * Initialize sine waves synthesizer and ff_sine_* tables.
185  */
186 void ff_atrac3p_init_dsp_static(void);
187 
188 /**
189  * Synthesize sine waves for a particular subband.
190  *
191  * @param[in]   ch_unit   pointer to the channel unit context
192  * @param[in]   fdsp      pointer to float DSP context
193  * @param[in]   ch_num    which channel to process
194  * @param[in]   sb        which subband to process
195  * @param[out]  out       receives processed data
196  */
197 void ff_atrac3p_generate_tones(Atrac3pChanUnitCtx *ch_unit, AVFloatDSPContext *fdsp,
198                                int ch_num, int sb, float *out);
199 
200 /**
201  * Perform power compensation aka noise dithering.
202  *
203  * @param[in]      ctx         ptr to the channel context
204  * @param[in]      fdsp        pointer to float DSP context
205  * @param[in]      ch_index    which channel to process
206  * @param[in,out]  sp          ptr to channel spectrum to process
207  * @param[in]      rng_index   indicates which RNG table to use
208  * @param[in]      sb_num      which subband to process
209  */
210 void ff_atrac3p_power_compensation(Atrac3pChanUnitCtx *ctx, AVFloatDSPContext *fdsp,
211                                    int ch_index, float *sp, int rng_index, int sb_num);
212 
213 /**
214  * Regular IMDCT and windowing without overlapping,
215  * with spectrum reversal in the odd subbands.
216  *
217  * @param[in]   fdsp       pointer to float DSP context
218  * @param[in]   mdct_ctx   pointer to MDCT transform context
219  * @param[in]   pIn        float input
220  * @param[out]  pOut       float output
221  * @param[in]   wind_id    which MDCT window to apply
222  * @param[in]   sb         subband number
223  */
224 void ff_atrac3p_imdct(AVFloatDSPContext *fdsp, FFTContext *mdct_ctx, float *pIn,
225                       float *pOut, int wind_id, int sb);
226 
227 /**
228  * Subband synthesis filter based on the polyphase quadrature (pseudo-QMF)
229  * filter bank.
230  *
231  * @param[in]      dct_ctx   ptr to the pre-initialized IDCT context
232  * @param[in,out]  hist      ptr to the filter history
233  * @param[in]      in        input data to process
234  * @param[out]     out       receives processed data
235  */
236 void ff_atrac3p_ipqf(FFTContext *dct_ctx, Atrac3pIPQFChannelCtx *hist,
237                      const float *in, float *out);
238 
239 extern const uint16_t ff_atrac3p_qu_to_spec_pos[33];
240 extern const float ff_atrac3p_sf_tab[64];
241 extern const float ff_atrac3p_mant_tab[8];
242 
243 #endif /* AVCODEC_ATRAC3PLUS_H */
244