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/*
* Opus decoder/demuxer common functions
* Copyright (c) 2012 Andrew D'Addesio
* Copyright (c) 2013-2014 Mozilla Corporation
* Copyright (c) 2016 Rostislav Pehlivanov <atomnuker@gmail.com>
*
* 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
*/
#ifndef AVCODEC_OPUS_CELT_H
#define AVCODEC_OPUS_CELT_H
#include <float.h>
#include "opus.h"
#include "mdct15.h"
#include "libavutil/float_dsp.h"
#include "libavutil/libm.h"
#define CELT_VECTORS 11
#define CELT_ALLOC_STEPS 6
#define CELT_FINE_OFFSET 21
#define CELT_MAX_FINE_BITS 8
#define CELT_NORM_SCALE 16384
#define CELT_QTHETA_OFFSET 4
#define CELT_QTHETA_OFFSET_TWOPHASE 16
#define CELT_EMPH_COEFF 0.85000610f
#define CELT_POSTFILTER_MINPERIOD 15
#define CELT_ENERGY_SILENCE (-28.0f)
enum CeltSpread {
CELT_SPREAD_NONE,
CELT_SPREAD_LIGHT,
CELT_SPREAD_NORMAL,
CELT_SPREAD_AGGRESSIVE
};
enum CeltBlockSize {
CELT_BLOCK_120,
CELT_BLOCK_240,
CELT_BLOCK_480,
CELT_BLOCK_960,
CELT_BLOCK_NB
};
typedef struct CeltBlock {
float energy[CELT_MAX_BANDS];
float prev_energy[2][CELT_MAX_BANDS];
uint8_t collapse_masks[CELT_MAX_BANDS];
/* buffer for mdct output + postfilter */
DECLARE_ALIGNED(32, float, buf)[2048];
DECLARE_ALIGNED(32, float, coeffs)[CELT_MAX_FRAME_SIZE];
/* postfilter parameters */
int pf_period_new;
float pf_gains_new[3];
int pf_period;
float pf_gains[3];
int pf_period_old;
float pf_gains_old[3];
float emph_coeff;
} CeltBlock;
struct CeltFrame {
// constant values that do not change during context lifetime
AVCodecContext *avctx;
MDCT15Context *imdct[4];
AVFloatDSPContext *dsp;
CeltBlock block[2];
int channels;
int output_channels;
enum CeltBlockSize size;
int start_band;
int end_band;
int coded_bands;
int transient;
int blocks; /* number of iMDCT blocks in the frame, depends on transient */
int blocksize; /* size of each block */
int silence; /* Frame is filled with silence */
int anticollapse_needed; /* Whether to expect an anticollapse bit */
int anticollapse; /* Encoded anticollapse bit */
int intensity_stereo;
int dual_stereo;
int flushed;
uint32_t seed;
enum CeltSpread spread;
/* Bit allocation */
int framebits;
int remaining;
int remaining2;
int fine_bits [CELT_MAX_BANDS];
int fine_priority[CELT_MAX_BANDS];
int pulses [CELT_MAX_BANDS];
int tf_change [CELT_MAX_BANDS];
DECLARE_ALIGNED(32, float, scratch)[22 * 8]; // MAX(ff_celt_freq_range) * 1<<CELT_MAX_LOG_BLOCKS
};
/* LCG for noise generation */
static av_always_inline uint32_t celt_rng(CeltFrame *f)
{
f->seed = 1664525 * f->seed + 1013904223;
return f->seed;
}
static av_always_inline void celt_renormalize_vector(float *X, int N, float gain)
{
int i;
float g = 1e-15f;
for (i = 0; i < N; i++)
g += X[i] * X[i];
g = gain / sqrtf(g);
for (i = 0; i < N; i++)
X[i] *= g;
}
int ff_celt_init(AVCodecContext *avctx, CeltFrame **f, int output_channels);
void ff_celt_free(CeltFrame **f);
void ff_celt_flush(CeltFrame *f);
int ff_celt_decode_frame(CeltFrame *f, OpusRangeCoder *rc, float **output,
int coded_channels, int frame_size, int startband, int endband);
#endif /* AVCODEC_OPUS_CELT_H */
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