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/*
* ATRAC3+ compatible decoder
*
* Copyright (c) 2010-2013 Maxim Poliakovski
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* Global structures, constants and data for ATRAC3+ decoder.
*/
#ifndef AVCODEC_ATRAC3PLUS_H
#define AVCODEC_ATRAC3PLUS_H
#include <stdint.h>
#include "libavutil/float_dsp.h"
#include "atrac.h"
#include "avcodec.h"
#include "fft.h"
#include "get_bits.h"
/** Global unit sizes */
#define ATRAC3P_SUBBANDS 16 ///< number of PQF subbands
#define ATRAC3P_SUBBAND_SAMPLES 128 ///< number of samples per subband
#define ATRAC3P_FRAME_SAMPLES (ATRAC3P_SUBBAND_SAMPLES * ATRAC3P_SUBBANDS)
#define ATRAC3P_PQF_FIR_LEN 12 ///< length of the prototype FIR of the PQF
/** Global constants */
#define ATRAC3P_POWER_COMP_OFF 15 ///< disable power compensation
/** ATRAC3+ channel unit types */
enum Atrac3pChannelUnitTypes {
CH_UNIT_MONO = 0, ///< unit containing one coded channel
CH_UNIT_STEREO = 1, ///< unit containing two jointly-coded channels
CH_UNIT_EXTENSION = 2, ///< unit containing extension information
CH_UNIT_TERMINATOR = 3 ///< unit sequence terminator
};
/** Per-channel IPQF history */
typedef struct Atrac3pIPQFChannelCtx {
DECLARE_ALIGNED(32, float, buf1)[ATRAC3P_PQF_FIR_LEN * 2][8];
DECLARE_ALIGNED(32, float, buf2)[ATRAC3P_PQF_FIR_LEN * 2][8];
int pos;
} Atrac3pIPQFChannelCtx;
/** Amplitude envelope of a group of sine waves */
typedef struct Atrac3pWaveEnvelope {
int has_start_point; ///< indicates start point within the GHA window
int has_stop_point; ///< indicates stop point within the GHA window
int start_pos; ///< start position expressed in n*4 samples
int stop_pos; ///< stop position expressed in n*4 samples
} Atrac3pWaveEnvelope;
/** Parameters of a group of sine waves */
typedef struct Atrac3pWavesData {
Atrac3pWaveEnvelope pend_env; ///< pending envelope from the previous frame
Atrac3pWaveEnvelope curr_env; ///< group envelope from the current frame
int num_wavs; ///< number of sine waves in the group
int start_index; ///< start index into global tones table for that subband
} Atrac3pWavesData;
/** Parameters of a single sine wave */
typedef struct Atrac3pWaveParam {
int freq_index; ///< wave frequency index
int amp_sf; ///< quantized amplitude scale factor
int amp_index; ///< quantized amplitude index
int phase_index; ///< quantized phase index
} Atrac3pWaveParam;
/** Sound channel parameters */
typedef struct Atrac3pChanParams {
int ch_num;
int num_coded_vals; ///< number of transmitted quant unit values
int fill_mode;
int split_point;
int table_type; ///< table type: 0 - tone?, 1- noise?
int qu_wordlen[32]; ///< array of word lengths for each quant unit
int qu_sf_idx[32]; ///< array of scale factor indexes for each quant unit
int qu_tab_idx[32]; ///< array of code table indexes for each quant unit
int16_t spectrum[2048]; ///< decoded IMDCT spectrum
uint8_t power_levs[5]; ///< power compensation levels
/* imdct window shape history (2 frames) for overlapping. */
uint8_t wnd_shape_hist[2][ATRAC3P_SUBBANDS]; ///< IMDCT window shape, 0=sine/1=steep
uint8_t *wnd_shape; ///< IMDCT window shape for current frame
uint8_t *wnd_shape_prev; ///< IMDCT window shape for previous frame
/* gain control data history (2 frames) for overlapping. */
AtracGainInfo gain_data_hist[2][ATRAC3P_SUBBANDS]; ///< gain control data for all subbands
AtracGainInfo *gain_data; ///< gain control data for next frame
AtracGainInfo *gain_data_prev; ///< gain control data for previous frame
int num_gain_subbands; ///< number of subbands with gain control data
/* tones data history (2 frames) for overlapping. */
Atrac3pWavesData tones_info_hist[2][ATRAC3P_SUBBANDS];
Atrac3pWavesData *tones_info;
Atrac3pWavesData *tones_info_prev;
} Atrac3pChanParams;
/* Per-unit sine wave parameters */
typedef struct Atrac3pWaveSynthParams {
int tones_present; ///< 1 - tones info present
int amplitude_mode; ///< 1 - low range, 0 - high range
int num_tone_bands; ///< number of PQF bands with tones
uint8_t tone_sharing[ATRAC3P_SUBBANDS]; ///< 1 - subband-wise tone sharing flags
uint8_t tone_master[ATRAC3P_SUBBANDS]; ///< 1 - subband-wise tone channel swapping
uint8_t phase_shift[ATRAC3P_SUBBANDS]; ///< 1 - subband-wise 180° phase shifting
int tones_index; ///< total sum of tones in this unit
Atrac3pWaveParam waves[48];
} Atrac3pWaveSynthParams;
/** Channel unit parameters */
typedef struct Atrac3pChanUnitCtx {
/* channel unit variables */
int unit_type; ///< unit type (mono/stereo)
int num_quant_units;
int num_subbands;
int used_quant_units; ///< number of quant units with coded spectrum
int num_coded_subbands; ///< number of subbands with coded spectrum
int mute_flag; ///< mute flag
int use_full_table; ///< 1 - full table list, 0 - restricted one
int noise_present; ///< 1 - global noise info present
int noise_level_index; ///< global noise level index
int noise_table_index; ///< global noise RNG table index
uint8_t swap_channels[ATRAC3P_SUBBANDS]; ///< 1 - perform subband-wise channel swapping
uint8_t negate_coeffs[ATRAC3P_SUBBANDS]; ///< 1 - subband-wise IMDCT coefficients negation
Atrac3pChanParams channels[2];
/* Variables related to GHA tones */
Atrac3pWaveSynthParams wave_synth_hist[2]; ///< waves synth history for two frames
Atrac3pWaveSynthParams *waves_info;
Atrac3pWaveSynthParams *waves_info_prev;
Atrac3pIPQFChannelCtx ipqf_ctx[2];
DECLARE_ALIGNED(32, float, prev_buf)[2][ATRAC3P_FRAME_SAMPLES]; ///< overlapping buffer
} Atrac3pChanUnitCtx;
/**
* Initialize VLC tables for bitstream parsing.
*/
void ff_atrac3p_init_vlcs(void);
/**
* Decode bitstream data of a channel unit.
*
* @param[in] gb the GetBit context
* @param[in,out] ctx ptr to the channel unit context
* @param[in] num_channels number of channels to process
* @param[in] avctx ptr to the AVCodecContext
* @return result code: 0 = OK, otherwise - error code
*/
int ff_atrac3p_decode_channel_unit(GetBitContext *gb, Atrac3pChanUnitCtx *ctx,
int num_channels, AVCodecContext *avctx);
/**
* Initialize IMDCT transform.
*
* @param[in] avctx ptr to the AVCodecContext
* @param[in] mdct_ctx pointer to MDCT transform context
*/
void ff_atrac3p_init_imdct(AVCodecContext *avctx, FFTContext *mdct_ctx);
/**
* Initialize sine waves synthesizer.
*/
void ff_atrac3p_init_wave_synth(void);
/**
* Synthesize sine waves for a particular subband.
*
* @param[in] ch_unit pointer to the channel unit context
* @param[in] fdsp pointer to float DSP context
* @param[in] ch_num which channel to process
* @param[in] sb which subband to process
* @param[out] out receives processed data
*/
void ff_atrac3p_generate_tones(Atrac3pChanUnitCtx *ch_unit, AVFloatDSPContext *fdsp,
int ch_num, int sb, float *out);
/**
* Perform power compensation aka noise dithering.
*
* @param[in] ctx ptr to the channel context
* @param[in] ch_index which channel to process
* @param[in,out] sp ptr to channel spectrum to process
* @param[in] rng_index indicates which RNG table to use
* @param[in] sb which subband to process
*/
void ff_atrac3p_power_compensation(Atrac3pChanUnitCtx *ctx, int ch_index,
float *sp, int rng_index, int sb_num);
/**
* Regular IMDCT and windowing without overlapping,
* with spectrum reversal in the odd subbands.
*
* @param[in] fdsp pointer to float DSP context
* @param[in] mdct_ctx pointer to MDCT transform context
* @param[in] pIn float input
* @param[out] pOut float output
* @param[in] wind_id which MDCT window to apply
* @param[in] sb subband number
*/
void ff_atrac3p_imdct(AVFloatDSPContext *fdsp, FFTContext *mdct_ctx, float *pIn,
float *pOut, int wind_id, int sb);
/**
* Subband synthesis filter based on the polyphase quadrature (pseudo-QMF)
* filter bank.
*
* @param[in] dct_ctx ptr to the pre-initialized IDCT context
* @param[in,out] hist ptr to the filter history
* @param[in] in input data to process
* @param[out] out receives processed data
*/
void ff_atrac3p_ipqf(FFTContext *dct_ctx, Atrac3pIPQFChannelCtx *hist,
const float *in, float *out);
extern const uint16_t ff_atrac3p_qu_to_spec_pos[33];
extern const float ff_atrac3p_sf_tab[64];
extern const float ff_atrac3p_mant_tab[8];
#endif /* AVCODEC_ATRAC3PLUS_H */
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