2 * ATRAC3+ compatible decoder
4 * Copyright (c) 2010-2013 Maxim Poliakovski
6 * This file is part of Libav.
8 * Libav 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 * Libav 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 Libav; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
25 * Global structures, constants and data for ATRAC3+ decoder.
28 #ifndef AVCODEC_ATRAC3PLUS_H
29 #define AVCODEC_ATRAC3PLUS_H
33 #include "libavutil/float_dsp.h"
36 #include "bitstream.h"
40 /** Global unit sizes */
41 #define ATRAC3P_SUBBANDS 16 ///< number of PQF subbands
42 #define ATRAC3P_SUBBAND_SAMPLES 128 ///< number of samples per subband
43 #define ATRAC3P_FRAME_SAMPLES (ATRAC3P_SUBBAND_SAMPLES * ATRAC3P_SUBBANDS)
45 #define ATRAC3P_PQF_FIR_LEN 12 ///< length of the prototype FIR of the PQF
47 /** Global constants */
48 #define ATRAC3P_POWER_COMP_OFF 15 ///< disable power compensation
50 /** ATRAC3+ channel unit types */
51 enum Atrac3pChannelUnitTypes {
52 CH_UNIT_MONO = 0, ///< unit containing one coded channel
53 CH_UNIT_STEREO = 1, ///< unit containing two jointly-coded channels
54 CH_UNIT_EXTENSION = 2, ///< unit containing extension information
55 CH_UNIT_TERMINATOR = 3 ///< unit sequence terminator
58 /** Per-channel IPQF history */
59 typedef struct Atrac3pIPQFChannelCtx {
60 DECLARE_ALIGNED(32, float, buf1)[ATRAC3P_PQF_FIR_LEN * 2][8];
61 DECLARE_ALIGNED(32, float, buf2)[ATRAC3P_PQF_FIR_LEN * 2][8];
63 } Atrac3pIPQFChannelCtx;
65 /** Amplitude envelope of a group of sine waves */
66 typedef struct Atrac3pWaveEnvelope {
67 int has_start_point; ///< indicates start point within the GHA window
68 int has_stop_point; ///< indicates stop point within the GHA window
69 int start_pos; ///< start position expressed in n*4 samples
70 int stop_pos; ///< stop position expressed in n*4 samples
71 } Atrac3pWaveEnvelope;
73 /** Parameters of a group of sine waves */
74 typedef struct Atrac3pWavesData {
75 Atrac3pWaveEnvelope pend_env; ///< pending envelope from the previous frame
76 Atrac3pWaveEnvelope curr_env; ///< group envelope from the current frame
77 int num_wavs; ///< number of sine waves in the group
78 int start_index; ///< start index into global tones table for that subband
81 /** Parameters of a single sine wave */
82 typedef struct Atrac3pWaveParam {
83 int freq_index; ///< wave frequency index
84 int amp_sf; ///< quantized amplitude scale factor
85 int amp_index; ///< quantized amplitude index
86 int phase_index; ///< quantized phase index
89 /** Sound channel parameters */
90 typedef struct Atrac3pChanParams {
92 int num_coded_vals; ///< number of transmitted quant unit values
95 int table_type; ///< table type: 0 - tone?, 1- noise?
96 int qu_wordlen[32]; ///< array of word lengths for each quant unit
97 int qu_sf_idx[32]; ///< array of scale factor indexes for each quant unit
98 int qu_tab_idx[32]; ///< array of code table indexes for each quant unit
99 int16_t spectrum[2048]; ///< decoded IMDCT spectrum
100 uint8_t power_levs[5]; ///< power compensation levels
102 /* imdct window shape history (2 frames) for overlapping. */
103 uint8_t wnd_shape_hist[2][ATRAC3P_SUBBANDS]; ///< IMDCT window shape, 0=sine/1=steep
104 uint8_t *wnd_shape; ///< IMDCT window shape for current frame
105 uint8_t *wnd_shape_prev; ///< IMDCT window shape for previous frame
107 /* gain control data history (2 frames) for overlapping. */
108 AtracGainInfo gain_data_hist[2][ATRAC3P_SUBBANDS]; ///< gain control data for all subbands
109 AtracGainInfo *gain_data; ///< gain control data for next frame
110 AtracGainInfo *gain_data_prev; ///< gain control data for previous frame
111 int num_gain_subbands; ///< number of subbands with gain control data
113 /* tones data history (2 frames) for overlapping. */
114 Atrac3pWavesData tones_info_hist[2][ATRAC3P_SUBBANDS];
115 Atrac3pWavesData *tones_info;
116 Atrac3pWavesData *tones_info_prev;
119 /* Per-unit sine wave parameters */
120 typedef struct Atrac3pWaveSynthParams {
121 int tones_present; ///< 1 - tones info present
122 int amplitude_mode; ///< 1 - low range, 0 - high range
123 int num_tone_bands; ///< number of PQF bands with tones
124 uint8_t tone_sharing[ATRAC3P_SUBBANDS]; ///< 1 - subband-wise tone sharing flags
125 uint8_t tone_master[ATRAC3P_SUBBANDS]; ///< 1 - subband-wise tone channel swapping
126 uint8_t phase_shift[ATRAC3P_SUBBANDS]; ///< 1 - subband-wise 180° phase shifting
127 int tones_index; ///< total sum of tones in this unit
128 Atrac3pWaveParam waves[48];
129 } Atrac3pWaveSynthParams;
131 /** Channel unit parameters */
132 typedef struct Atrac3pChanUnitCtx {
133 /* channel unit variables */
134 int unit_type; ///< unit type (mono/stereo)
137 int used_quant_units; ///< number of quant units with coded spectrum
138 int num_coded_subbands; ///< number of subbands with coded spectrum
139 int mute_flag; ///< mute flag
140 int use_full_table; ///< 1 - full table list, 0 - restricted one
141 int noise_present; ///< 1 - global noise info present
142 int noise_level_index; ///< global noise level index
143 int noise_table_index; ///< global noise RNG table index
144 uint8_t swap_channels[ATRAC3P_SUBBANDS]; ///< 1 - perform subband-wise channel swapping
145 uint8_t negate_coeffs[ATRAC3P_SUBBANDS]; ///< 1 - subband-wise IMDCT coefficients negation
146 Atrac3pChanParams channels[2];
148 /* Variables related to GHA tones */
149 Atrac3pWaveSynthParams wave_synth_hist[2]; ///< waves synth history for two frames
150 Atrac3pWaveSynthParams *waves_info;
151 Atrac3pWaveSynthParams *waves_info_prev;
153 Atrac3pIPQFChannelCtx ipqf_ctx[2];
154 DECLARE_ALIGNED(32, float, prev_buf)[2][ATRAC3P_FRAME_SAMPLES]; ///< overlapping buffer
155 } Atrac3pChanUnitCtx;
158 * Initialize VLC tables for bitstream parsing.
160 * @param[in] codec ptr to the AVCodec
162 void ff_atrac3p_init_vlcs(AVCodec *codec);
165 * Decode bitstream data of a channel unit.
167 * @param[in] bc the Bitstream context
168 * @param[in,out] ctx ptr to the channel unit context
169 * @param[in] num_channels number of channels to process
170 * @param[in] avctx ptr to the AVCodecContext
171 * @return result code: 0 = OK, otherwise - error code
173 int ff_atrac3p_decode_channel_unit(BitstreamContext *bc, Atrac3pChanUnitCtx *ctx,
174 int num_channels, AVCodecContext *avctx);
177 * Initialize IMDCT transform.
179 * @param[in] avctx ptr to the AVCodecContext
180 * @param[in] mdct_ctx pointer to MDCT transform context
182 void ff_atrac3p_init_imdct(AVCodecContext *avctx, FFTContext *mdct_ctx);
185 * Initialize sine waves synthesizer.
187 void ff_atrac3p_init_wave_synth(void);
190 * Synthesize sine waves for a particular subband.
192 * @param[in] ch_unit pointer to the channel unit context
193 * @param[in] fdsp pointer to float DSP context
194 * @param[in] ch_num which channel to process
195 * @param[in] sb which subband to process
196 * @param[out] out receives processed data
198 void ff_atrac3p_generate_tones(Atrac3pChanUnitCtx *ch_unit, AVFloatDSPContext *fdsp,
199 int ch_num, int sb, float *out);
202 * Perform power compensation aka noise dithering.
204 * @param[in] ctx ptr to the channel 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
210 void ff_atrac3p_power_compensation(Atrac3pChanUnitCtx *ctx, int ch_index,
211 float *sp, int rng_index, int sb_num);
214 * Regular IMDCT and windowing without overlapping,
215 * with spectrum reversal in the odd subbands.
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
224 void ff_atrac3p_imdct(AVFloatDSPContext *fdsp, FFTContext *mdct_ctx, float *pIn,
225 float *pOut, int wind_id, int sb);
228 * Subband synthesis filter based on the polyphase quadrature (pseudo-QMF)
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
236 void ff_atrac3p_ipqf(FFTContext *dct_ctx, Atrac3pIPQFChannelCtx *hist,
237 const float *in, float *out);
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];
243 #endif /* AVCODEC_ATRAC3PLUS_H */