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/*
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 * Spectral Band Replication definitions and structures
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 * Copyright (c) 2008-2009 Robert Swain ( rob opendot cl )
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 * Copyright (c) 2010      Alex Converse <alex.converse@gmail.com>
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 *
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 * This file is part of FFmpeg.
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 *
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 * FFmpeg is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU Lesser General Public
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 * License as published by the Free Software Foundation; either
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 * version 2.1 of the License, or (at your option) any later version.
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 *
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 * FFmpeg is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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 * Lesser General Public License for more details.
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 *
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 * You should have received a copy of the GNU Lesser General Public
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 * License along with FFmpeg; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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 */
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/**
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 * @file
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 * Spectral Band Replication definitions and structures
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 * @author Robert Swain ( rob opendot cl )
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 */
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#ifndef AVCODEC_SBR_H
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#define AVCODEC_SBR_H
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#include <stdint.h>
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#include "fft.h"
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/**
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 * Spectral Band Replication header - spectrum parameters that invoke a reset if they differ from the previous header.
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 */
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typedef struct {
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    uint8_t bs_start_freq;
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    uint8_t bs_stop_freq;
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    uint8_t bs_xover_band;
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    /**
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     * @defgroup bs_header_extra_1     Variables associated with bs_header_extra_1
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     * @{
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     */
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    uint8_t bs_freq_scale;
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    uint8_t bs_alter_scale;
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    uint8_t bs_noise_bands;
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    /** @} */
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} SpectrumParameters;
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#define SBR_SYNTHESIS_BUF_SIZE ((1280-128)*2)
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/**
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 * Spectral Band Replication per channel data
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 */
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typedef struct {
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    /**
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     * @defgroup bitstream     Main bitstream data variables
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     * @{
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     */
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    unsigned           bs_frame_class;
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    unsigned           bs_add_harmonic_flag;
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    unsigned           bs_num_env;
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    uint8_t            bs_freq_res[7];
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    unsigned           bs_num_noise;
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    uint8_t            bs_df_env[5];
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    uint8_t            bs_df_noise[2];
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    uint8_t            bs_invf_mode[2][5];
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    uint8_t            bs_add_harmonic[48];
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    unsigned           bs_amp_res;
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    /** @} */
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    /**
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     * @defgroup state         State variables
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     * @{
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     */
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    DECLARE_ALIGNED(16, float, synthesis_filterbank_samples)[SBR_SYNTHESIS_BUF_SIZE];
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    DECLARE_ALIGNED(16, float, analysis_filterbank_samples) [1312];
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    int                synthesis_filterbank_samples_offset;
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    ///l_APrev and l_A
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    int                e_a[2];
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    ///Chirp factors
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    float              bw_array[5];
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    ///QMF values of the original signal
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    float              W[2][32][32][2];
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    ///QMF output of the HF adjustor
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    float              Y[2][38][64][2];
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    float              g_temp[42][48];
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    float              q_temp[42][48];
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    uint8_t            s_indexmapped[8][48];
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    ///Envelope scalefactors
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    float              env_facs[6][48];
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    ///Noise scalefactors
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    float              noise_facs[3][5];
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    ///Envelope time borders
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    uint8_t            t_env[8];
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    ///Envelope time border of the last envelope of the previous frame
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    uint8_t            t_env_num_env_old;
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    ///Noise time borders
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    uint8_t            t_q[3];
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    unsigned           f_indexnoise;
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    unsigned           f_indexsine;
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    /** @} */
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} SBRData;
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/**
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 * Spectral Band Replication
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 */
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typedef struct {
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    int                sample_rate;
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    int                start;
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    int                reset;
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    SpectrumParameters spectrum_params;
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    int                bs_amp_res_header;
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    /**
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     * @defgroup bs_header_extra_2     variables associated with bs_header_extra_2
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     * @{
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     */
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    unsigned           bs_limiter_bands;
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    unsigned           bs_limiter_gains;
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    unsigned           bs_interpol_freq;
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    unsigned           bs_smoothing_mode;
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    /** @} */
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    unsigned           bs_coupling;
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    unsigned           k[5]; ///< k0, k1, k2
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    ///kx', and kx respectively, kx is the first QMF subband where SBR is used.
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    ///kx' is its value from the previous frame
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    unsigned           kx[2];
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    ///M' and M respectively, M is the number of QMF subbands that use SBR.
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    unsigned           m[2];
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    ///The number of frequency bands in f_master
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    unsigned           n_master;
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    SBRData            data[2];
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    ///N_Low and N_High respectively, the number of frequency bands for low and high resolution
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    unsigned           n[2];
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    ///Number of noise floor bands
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    unsigned           n_q;
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    ///Number of limiter bands
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    unsigned           n_lim;
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    ///The master QMF frequency grouping
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    uint16_t           f_master[49];
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    ///Frequency borders for low resolution SBR
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    uint16_t           f_tablelow[25];
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    ///Frequency borders for high resolution SBR
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    uint16_t           f_tablehigh[49];
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    ///Frequency borders for noise floors
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    uint16_t           f_tablenoise[6];
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    ///Frequency borders for the limiter
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    uint16_t           f_tablelim[29];
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    unsigned           num_patches;
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    uint8_t            patch_num_subbands[6];
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    uint8_t            patch_start_subband[6];
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    ///QMF low frequency input to the HF generator
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    float              X_low[32][40][2];
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    ///QMF output of the HF generator
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    float              X_high[64][40][2];
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    ///QMF values of the reconstructed signal
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    DECLARE_ALIGNED(16, float, X)[2][2][32][64];
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    ///Zeroth coefficient used to filter the subband signals
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    float              alpha0[64][2];
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    ///First coefficient used to filter the subband signals
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    float              alpha1[64][2];
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    ///Dequantized envelope scalefactors, remapped
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    float              e_origmapped[7][48];
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    ///Dequantized noise scalefactors, remapped
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    float              q_mapped[7][48];
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    ///Sinusoidal presence, remapped
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    uint8_t            s_mapped[7][48];
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    ///Estimated envelope
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    float              e_curr[7][48];
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    ///Amplitude adjusted noise scalefactors
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    float              q_m[7][48];
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    ///Sinusoidal levels
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    float              s_m[7][48];
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    float              gain[7][48];
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    DECLARE_ALIGNED(16, float, qmf_filter_scratch)[5][64];
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    FFTContext         mdct_ana;
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    FFTContext         mdct;
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} SpectralBandReplication;
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#endif /* AVCODEC_SBR_H */