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atrac3plus.h
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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 "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 */
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 {
61  int pos;
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
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
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
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;
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. */
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
129 
130 /** Channel unit parameters */
131 typedef struct Atrac3pChanUnitCtx {
132  /* channel unit variables */
133  int unit_type; ///< unit type (mono/stereo)
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
146 
147  /* Variables related to GHA tones */
148  Atrac3pWaveSynthParams wave_synth_hist[2]; ///< waves synth history for two frames
151 
153  DECLARE_ALIGNED(32, float, prev_buf)[2][ATRAC3P_FRAME_SAMPLES]; ///< overlapping buffer
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  */
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  */
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  */
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 */