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https://git.ffmpeg.org/ffmpeg.git
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8f2f166c99
Signed-off-by: James Almer <jamrial@gmail.com>
646 lines
37 KiB
C
646 lines
37 KiB
C
/*
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* ATRAC3+ compatible decoder
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*
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* Copyright (c) 2010-2013 Maxim Poliakovski
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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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* DSP functions for ATRAC3+ decoder.
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*/
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#include <math.h>
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#include "libavutil/float_dsp.h"
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#include "libavutil/libm.h"
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#include "avcodec.h"
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#include "sinewin.h"
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#include "fft.h"
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#include "atrac3plus.h"
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/**
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* Map quant unit number to its position in the spectrum.
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* To get the number of spectral lines in each quant unit do the following:
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* num_specs = qu_to_spec_pos[i+1] - qu_to_spec_pos[i]
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*/
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const uint16_t ff_atrac3p_qu_to_spec_pos[33] = {
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0, 16, 32, 48, 64, 80, 96, 112,
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128, 160, 192, 224, 256, 288, 320, 352,
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384, 448, 512, 576, 640, 704, 768, 896,
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1024, 1152, 1280, 1408, 1536, 1664, 1792, 1920,
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2048
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};
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/* Scalefactors table. */
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/* Approx. Equ: pow(2.0, (i - 16.0 + 0.501783948) / 3.0) */
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const float ff_atrac3p_sf_tab[64] = {
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0.027852058, 0.0350914, 0.044212341, 0.055704117, 0.0701828,
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0.088424683, 0.11140823, 0.1403656, 0.17684937, 0.22281647, 0.2807312, 0.35369873,
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0.44563293, 0.5614624, 0.70739746, 0.89126587, 1.1229248, 1.4147949, 1.7825317,
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2.2458496, 2.8295898, 3.5650635, 4.4916992, 5.6591797, 7.130127, 8.9833984,
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11.318359, 14.260254, 17.966797, 22.636719, 28.520508, 35.933594, 45.273438,
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57.041016, 71.867188, 90.546875, 114.08203, 143.73438, 181.09375, 228.16406,
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287.46875, 362.1875, 456.32812, 574.9375, 724.375, 912.65625, 1149.875,
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1448.75, 1825.3125, 2299.75, 2897.5, 3650.625, 4599.5, 5795.0,
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7301.25, 9199.0, 11590.0, 14602.5, 18398.0, 23180.0, 29205.0,
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36796.0, 46360.0, 58410.0
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};
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/* Mantissa table. */
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/* pow(10, x * log10(2) + 0.05) / 2 / ([1,2,3,5,7,15,31] + 0.5) */
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const float ff_atrac3p_mant_tab[8] = {
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0.0,
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0.74801636,
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0.44882202,
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0.32058716,
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0.20400238,
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0.1496048,
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0.07239151,
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0.035619736
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};
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#define ATRAC3P_MDCT_SIZE (ATRAC3P_SUBBAND_SAMPLES * 2)
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av_cold void ff_atrac3p_init_imdct(AVCodecContext *avctx, FFTContext *mdct_ctx)
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{
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ff_init_ff_sine_windows(7);
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ff_init_ff_sine_windows(6);
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/* Initialize the MDCT transform. */
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ff_mdct_init(mdct_ctx, 8, 1, -1.0);
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}
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#define TWOPI (2 * M_PI)
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#define DEQUANT_PHASE(ph) (((ph) & 0x1F) << 6)
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static DECLARE_ALIGNED(32, float, sine_table)[2048]; ///< wave table
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static DECLARE_ALIGNED(32, float, hann_window)[256]; ///< Hann windowing function
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static float amp_sf_tab[64]; ///< scalefactors for quantized amplitudes
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av_cold void ff_atrac3p_init_wave_synth(void)
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{
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int i;
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/* generate sine wave table */
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for (i = 0; i < 2048; i++)
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sine_table[i] = sin(TWOPI * i / 2048);
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/* generate Hann window */
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for (i = 0; i < 256; i++)
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hann_window[i] = (1.0f - cos(TWOPI * i / 256.0f)) * 0.5f;
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/* generate amplitude scalefactors table */
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for (i = 0; i < 64; i++)
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amp_sf_tab[i] = exp2f((i - 3) / 4.0f);
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}
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/**
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* Synthesize sine waves according to given parameters.
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*
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* @param[in] synth_param ptr to common synthesis parameters
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* @param[in] waves_info parameters for each sine wave
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* @param[in] envelope envelope data for all waves in a group
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* @param[in] fdsp ptr to floating-point DSP context
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* @param[in] invert_phase flag indicating 180° phase shift
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* @param[in] reg_offset region offset for trimming envelope data
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* @param[out] out receives sythesized data
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*/
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static void waves_synth(Atrac3pWaveSynthParams *synth_param,
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Atrac3pWavesData *waves_info,
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Atrac3pWaveEnvelope *envelope,
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AVFloatDSPContext *fdsp,
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int invert_phase, int reg_offset, float *out)
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{
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int i, wn, inc, pos;
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double amp;
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Atrac3pWaveParam *wave_param = &synth_param->waves[waves_info->start_index];
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for (wn = 0; wn < waves_info->num_wavs; wn++, wave_param++) {
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/* amplitude dequantization */
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amp = amp_sf_tab[wave_param->amp_sf] *
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(!synth_param->amplitude_mode
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? (wave_param->amp_index + 1) / 15.13f
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: 1.0f);
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inc = wave_param->freq_index;
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pos = DEQUANT_PHASE(wave_param->phase_index) - (reg_offset ^ 128) * inc & 2047;
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/* waveform generation */
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for (i = 0; i < 128; i++) {
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out[i] += sine_table[pos] * amp;
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pos = (pos + inc) & 2047;
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}
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}
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/* invert phase if requested */
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if (invert_phase)
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fdsp->vector_fmul_scalar(out, out, -1.0f, 128);
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/* fade in with steep Hann window if requested */
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if (envelope->has_start_point) {
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pos = (envelope->start_pos << 2) - reg_offset;
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if (pos > 0 && pos <= 128) {
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memset(out, 0, pos * sizeof(*out));
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if (!envelope->has_stop_point ||
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envelope->start_pos != envelope->stop_pos) {
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out[pos + 0] *= hann_window[0];
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out[pos + 1] *= hann_window[32];
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out[pos + 2] *= hann_window[64];
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out[pos + 3] *= hann_window[96];
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}
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}
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}
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/* fade out with steep Hann window if requested */
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if (envelope->has_stop_point) {
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pos = (envelope->stop_pos + 1 << 2) - reg_offset;
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if (pos > 0 && pos <= 128) {
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out[pos - 4] *= hann_window[96];
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out[pos - 3] *= hann_window[64];
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out[pos - 2] *= hann_window[32];
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out[pos - 1] *= hann_window[0];
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memset(&out[pos], 0, (128 - pos) * sizeof(out[pos]));
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}
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}
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}
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void ff_atrac3p_generate_tones(Atrac3pChanUnitCtx *ch_unit, AVFloatDSPContext *fdsp,
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int ch_num, int sb, float *out)
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{
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DECLARE_ALIGNED(32, float, wavreg1)[128] = { 0 };
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DECLARE_ALIGNED(32, float, wavreg2)[128] = { 0 };
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int i, reg1_env_nonzero, reg2_env_nonzero;
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Atrac3pWavesData *tones_now = &ch_unit->channels[ch_num].tones_info_prev[sb];
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Atrac3pWavesData *tones_next = &ch_unit->channels[ch_num].tones_info[sb];
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/* reconstruct full envelopes for both overlapping regions
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* from truncated bitstream data */
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if (tones_next->pend_env.has_start_point &&
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tones_next->pend_env.start_pos < tones_next->pend_env.stop_pos) {
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tones_next->curr_env.has_start_point = 1;
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tones_next->curr_env.start_pos = tones_next->pend_env.start_pos + 32;
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} else if (tones_now->pend_env.has_start_point) {
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tones_next->curr_env.has_start_point = 1;
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tones_next->curr_env.start_pos = tones_now->pend_env.start_pos;
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} else {
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tones_next->curr_env.has_start_point = 0;
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tones_next->curr_env.start_pos = 0;
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}
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if (tones_now->pend_env.has_stop_point &&
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tones_now->pend_env.stop_pos >= tones_next->curr_env.start_pos) {
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tones_next->curr_env.has_stop_point = 1;
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tones_next->curr_env.stop_pos = tones_now->pend_env.stop_pos;
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} else if (tones_next->pend_env.has_stop_point) {
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tones_next->curr_env.has_stop_point = 1;
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tones_next->curr_env.stop_pos = tones_next->pend_env.stop_pos + 32;
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} else {
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tones_next->curr_env.has_stop_point = 0;
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tones_next->curr_env.stop_pos = 64;
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}
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/* is the visible part of the envelope non-zero? */
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reg1_env_nonzero = (tones_now->curr_env.stop_pos < 32) ? 0 : 1;
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reg2_env_nonzero = (tones_next->curr_env.start_pos >= 32) ? 0 : 1;
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/* synthesize waves for both overlapping regions */
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if (tones_now->num_wavs && reg1_env_nonzero)
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waves_synth(ch_unit->waves_info_prev, tones_now, &tones_now->curr_env,
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fdsp, ch_unit->waves_info_prev->invert_phase[sb] & ch_num,
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128, wavreg1);
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if (tones_next->num_wavs && reg2_env_nonzero)
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waves_synth(ch_unit->waves_info, tones_next, &tones_next->curr_env, fdsp,
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ch_unit->waves_info->invert_phase[sb] & ch_num, 0, wavreg2);
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/* Hann windowing for non-faded wave signals */
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if (tones_now->num_wavs && tones_next->num_wavs &&
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reg1_env_nonzero && reg2_env_nonzero) {
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fdsp->vector_fmul(wavreg1, wavreg1, &hann_window[128], 128);
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fdsp->vector_fmul(wavreg2, wavreg2, hann_window, 128);
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} else {
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if (tones_now->num_wavs && !tones_now->curr_env.has_stop_point)
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fdsp->vector_fmul(wavreg1, wavreg1, &hann_window[128], 128);
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if (tones_next->num_wavs && !tones_next->curr_env.has_start_point)
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fdsp->vector_fmul(wavreg2, wavreg2, hann_window, 128);
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}
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/* Overlap and add to residual */
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for (i = 0; i < 128; i++)
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out[i] += wavreg1[i] + wavreg2[i];
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}
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static const int subband_to_powgrp[ATRAC3P_SUBBANDS] = {
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0, 1, 1, 2, 2, 2, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4
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};
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/* noise table for power compensation */
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static const float noise_tab[1024] = {
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-0.01358032, -0.05593872, 0.01696777, -0.14871216, -0.26412964, -0.09893799, 0.25723267,
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0.02008057, -0.72235107, -0.44351196, -0.22985840, 0.16833496, 0.46902466, 0.05917358,
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-0.15179443, 0.41299438, -0.01287842, 0.13360596, 0.43557739, -0.09530640, -0.58422852,
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0.39266968, -0.08343506, -0.25604248, 0.22848511, 0.26013184, -0.65588379, 0.17288208,
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-0.08673096, -0.05203247, 0.07299805, -0.28665161, -0.35806274, 0.06552124, -0.09387207,
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0.21099854, -0.28347778, -0.72402954, 0.05050659, -0.10635376, -0.18853760, 0.29724121,
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0.20703125, -0.29791260, -0.37634277, 0.47970581, -0.09976196, 0.32641602, -0.29248047,
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-0.28237915, 0.26028442, -0.36157227, 0.22042847, -0.03222656, -0.37268066, -0.03759766,
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0.09909058, 0.23284912, 0.19320679, 0.14453125, -0.02139282, -0.19702148, 0.31533813,
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-0.16741943, 0.35031128, -0.35656738, -0.66128540, -0.00701904, 0.20898438, 0.26837158,
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-0.33706665, -0.04568481, 0.12600708, 0.10284424, 0.07321167, -0.18280029, 0.38101196,
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0.21301270, 0.04541016, 0.01156616, -0.26391602, -0.02346802, -0.22125244, 0.29760742,
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-0.36233521, -0.31314087, -0.13967896, -0.11276245, -0.19433594, 0.34490967, 0.02343750,
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0.21963501, -0.02777100, -0.67678833, -0.08999634, 0.14233398, -0.27697754, 0.51422119,
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-0.05047607, 0.48327637, 0.37167358, -0.60806274, 0.18728638, -0.15191650, 0.00637817,
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0.02832031, -0.15618896, 0.60644531, 0.21826172, 0.06384277, -0.31863403, 0.08816528,
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0.15447998, -0.07015991, -0.08154297, -0.40966797, -0.39785767, -0.11709595, 0.22052002,
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0.18466187, -0.17257690, 0.03759766, -0.06195068, 0.00433350, 0.12176514, 0.34011841,
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0.25610352, -0.05294800, 0.41033936, 0.16854858, -0.76187134, 0.13845825, -0.19418335,
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-0.21524048, -0.44412231, -0.08160400, -0.28195190, -0.01873779, 0.15524292, -0.37438965,
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-0.44860840, 0.43096924, -0.24746704, 0.49856567, 0.14859009, 0.38159180, 0.20541382,
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-0.39175415, -0.65850830, -0.43716431, 0.13037109, -0.05111694, 0.39956665, 0.21447754,
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-0.04861450, 0.33654785, 0.10589600, -0.88085938, -0.30822754, 0.38577271, 0.30047607,
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0.38836670, 0.09118652, -0.36477661, -0.01641846, -0.23031616, 0.26058960, 0.18859863,
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-0.21868896, -0.17861938, -0.29754639, 0.09777832, 0.10806274, -0.51605225, 0.00076294,
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0.13259888, 0.11090088, -0.24084473, 0.24957275, 0.01379395, -0.04141235, -0.04937744,
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0.57394409, 0.27410889, 0.27587891, 0.45013428, -0.32592773, 0.11160278, -0.00970459,
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0.29092407, 0.03356934, -0.70925903, 0.04882812, 0.43499756, 0.07720947, -0.27554321,
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-0.01742554, -0.08413696, -0.04028320, -0.52850342, -0.07330322, 0.05181885, 0.21362305,
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-0.18765259, 0.07058716, -0.03009033, 0.32662964, 0.27023315, -0.28002930, 0.17568970,
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0.03338623, 0.30242920, -0.03921509, 0.32174683, -0.23733521, 0.08575439, -0.38269043,
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0.09194946, -0.07238770, 0.17941284, -0.51278687, -0.25146484, 0.19790649, -0.19195557,
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0.16549683, 0.42456055, 0.39129639, -0.02868652, 0.17980957, 0.24902344, -0.76583862,
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-0.20959473, 0.61013794, 0.37011719, 0.36859131, -0.04486084, 0.10678101, -0.15994263,
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-0.05328369, 0.28463745, -0.06420898, -0.36987305, -0.28009033, -0.11764526, 0.04312134,
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-0.08038330, 0.04885864, -0.03067017, -0.00042725, 0.34289551, -0.00988770, 0.34838867,
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0.32516479, -0.16271973, 0.38269043, 0.03240967, 0.12417603, -0.14331055, -0.34902954,
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-0.18325806, 0.29421997, 0.44284058, 0.75170898, -0.67245483, -0.12176514, 0.27914429,
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-0.29806519, 0.19863892, 0.30087280, 0.22680664, -0.36633301, -0.32534790, -0.57553101,
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-0.16641235, 0.43811035, 0.08331299, 0.15942383, 0.26516724, -0.24240112, -0.11761475,
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-0.16827393, -0.14260864, 0.46343994, 0.11804199, -0.55514526, -0.02520752, -0.14309692,
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0.00448608, 0.02749634, -0.30545044, 0.70965576, 0.45108032, 0.66439819, -0.68255615,
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-0.12496948, 0.09146118, -0.21109009, -0.23791504, 0.79943848, -0.35205078, -0.24963379,
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0.18719482, -0.19079590, 0.07458496, 0.07623291, -0.28781128, -0.37121582, -0.19580078,
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-0.01773071, -0.16717529, 0.13040161, 0.14672852, 0.42379761, 0.03582764, 0.11431885,
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0.05145264, 0.44702148, 0.08963013, 0.01367188, -0.54519653, -0.12692261, 0.21176147,
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0.04925537, 0.30670166, -0.11029053, 0.19555664, -0.27740479, 0.23043823, 0.15554810,
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-0.19299316, -0.25729370, 0.17800903, -0.03579712, -0.05065918, -0.06933594, -0.09500122,
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-0.07821655, 0.23889160, -0.31900024, 0.03073120, -0.00415039, 0.61315918, 0.37176514,
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-0.13442993, -0.15536499, -0.19216919, -0.37899780, 0.19992065, 0.02630615, -0.12573242,
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0.25927734, -0.02447510, 0.29629517, -0.40731812, -0.17333984, 0.24310303, -0.10607910,
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0.14828491, 0.08792114, -0.18743896, -0.05572510, -0.04833984, 0.10473633, -0.29028320,
|
|
-0.67687988, -0.28170776, -0.41687012, 0.05413818, -0.23284912, 0.09555054, -0.08969116,
|
|
-0.15112305, 0.12738037, 0.35986328, 0.28948975, 0.30691528, 0.23956299, 0.06973267,
|
|
-0.31198120, -0.18450928, 0.22280884, -0.21600342, 0.23522949, -0.61840820, -0.13012695,
|
|
0.26412964, 0.47320557, -0.26440430, 0.38757324, 0.17352295, -0.26104736, -0.25866699,
|
|
-0.12274170, -0.29733276, 0.07687378, 0.18588257, -0.08880615, 0.31185913, 0.05313110,
|
|
-0.10885620, -0.14901733, -0.22323608, -0.08538818, 0.19812012, 0.19732666, -0.18927002,
|
|
0.29058838, 0.25555420, -0.48599243, 0.18768311, 0.01345825, 0.34887695, 0.21530151,
|
|
0.19857788, 0.18661499, -0.01394653, -0.09063721, -0.38781738, 0.27160645, -0.20379639,
|
|
-0.32119751, -0.23889160, 0.27096558, 0.24951172, 0.07922363, 0.07479858, -0.50946045,
|
|
0.10220337, 0.58364868, -0.19503784, -0.18560791, -0.01165771, 0.47195435, 0.22430420,
|
|
-0.38635254, -0.03732300, -0.09179688, 0.06991577, 0.15106201, 0.20605469, -0.05969238,
|
|
-0.41821289, 0.12231445, -0.04672241, -0.05117798, -0.11523438, -0.51849365, -0.04077148,
|
|
0.44284058, -0.64086914, 0.17019653, 0.02236938, 0.22848511, -0.23214722, -0.32354736,
|
|
-0.14068604, -0.29690552, -0.19891357, 0.02774048, -0.20965576, -0.52191162, -0.19299316,
|
|
-0.07290649, 0.49053955, -0.22302246, 0.05642700, 0.13122559, -0.20819092, -0.83590698,
|
|
-0.08181763, 0.26797485, -0.00091553, -0.09457397, 0.17089844, -0.27020264, 0.30270386,
|
|
0.05496216, 0.09564209, -0.08590698, 0.02130127, 0.35931396, 0.21728516, -0.15396118,
|
|
-0.05053711, 0.02719116, 0.16302490, 0.43212891, 0.10229492, -0.40820312, 0.21646118,
|
|
0.08435059, -0.11145020, -0.39962769, -0.05618286, -0.10223389, -0.60839844, 0.33724976,
|
|
-0.06341553, -0.47369385, -0.32852173, 0.05242920, 0.19635010, -0.19137573, -0.67901611,
|
|
0.16180420, 0.05133057, -0.22283936, 0.09646606, 0.24288940, -0.45007324, 0.08804321,
|
|
0.14053345, 0.22619629, -0.01000977, 0.36355591, -0.19863892, -0.30364990, -0.24118042,
|
|
-0.57461548, 0.26498413, 0.04345703, -0.09796143, -0.47714233, -0.23739624, 0.18737793,
|
|
0.08926392, -0.02795410, 0.00305176, -0.08700562, -0.38711548, 0.03222656, 0.10940552,
|
|
-0.41906738, -0.01620483, -0.47061157, 0.37985229, -0.21624756, 0.47976685, -0.20046997,
|
|
-0.62533569, -0.26907349, -0.02877808, 0.00671387, -0.29071045, -0.24685669, -0.15722656,
|
|
-0.26055908, 0.29968262, 0.28225708, -0.08990479, -0.16748047, -0.46759033, -0.25067139,
|
|
-0.25183105, -0.45932007, 0.05828857, 0.29006958, 0.23840332, -0.17974854, 0.26931763,
|
|
0.10696411, -0.06848145, -0.17126465, -0.10522461, -0.55386353, -0.42306519, -0.07608032,
|
|
0.24380493, 0.38586426, 0.16882324, 0.26751709, 0.17303467, 0.35809326, -0.22094727,
|
|
-0.30703735, -0.28497314, -0.04321289, 0.15219116, -0.17071533, -0.39334106, 0.03439331,
|
|
-0.10809326, -0.30590820, 0.26449585, -0.07412720, 0.13638306, -0.01062012, 0.27996826,
|
|
0.04397583, -0.05557251, -0.56933594, 0.03363037, -0.00949097, 0.52642822, -0.44329834,
|
|
0.28308105, -0.05499268, -0.23312378, -0.29870605, -0.05123901, 0.26831055, -0.35238647,
|
|
-0.30993652, 0.34646606, -0.19775391, 0.44595337, 0.13769531, 0.45358276, 0.19961548,
|
|
0.42681885, 0.15722656, 0.00128174, 0.23757935, 0.40988159, 0.25164795, -0.00732422,
|
|
-0.12405396, -0.43420410, -0.00402832, 0.34243774, 0.36264038, 0.18807983, -0.09301758,
|
|
-0.10296631, 0.05532837, -0.31652832, 0.14337158, 0.35040283, 0.32540894, 0.05728149,
|
|
-0.12030029, -0.25942993, -0.20312500, -0.16491699, -0.46051025, -0.08004761, 0.50772095,
|
|
0.16168213, 0.28439331, 0.08105469, -0.19104004, 0.38589478, -0.16400146, -0.25454712,
|
|
0.20281982, -0.20730591, -0.06311035, 0.32937622, 0.15032959, -0.05340576, 0.30487061,
|
|
-0.11648560, 0.38009644, -0.20062256, 0.43466187, 0.01150513, 0.35754395, -0.13146973,
|
|
0.67489624, 0.05212402, 0.27914429, -0.39431763, 0.75308228, -0.13366699, 0.24453735,
|
|
0.42248535, -0.65905762, -0.00546265, -0.03491211, -0.13659668, -0.08294678, -0.45666504,
|
|
0.27188110, 0.12731934, 0.61148071, 0.10449219, -0.28836060, 0.00091553, 0.24618530,
|
|
0.13119507, 0.05685425, 0.17355347, 0.42034912, 0.08514404, 0.24536133, 0.18951416,
|
|
-0.19107056, -0.15036011, 0.02334595, 0.54986572, 0.32321167, -0.16104126, -0.03054810,
|
|
0.43594360, 0.17309570, 0.61053467, 0.24731445, 0.33334351, 0.15240479, 0.15588379,
|
|
0.36425781, -0.30407715, -0.13302612, 0.00427246, 0.04171753, -0.33178711, 0.34216309,
|
|
-0.12463379, -0.02764893, 0.05905151, -0.31436157, 0.16531372, 0.34542847, -0.03292847,
|
|
0.12527466, -0.12313843, -0.13171387, 0.04757690, -0.45095825, -0.19085693, 0.35342407,
|
|
-0.23239136, -0.34387207, 0.11264038, -0.15740967, 0.05273438, 0.74942017, 0.21505737,
|
|
0.08514404, -0.42391968, -0.19531250, 0.35293579, 0.25305176, 0.15731812, -0.70324707,
|
|
-0.21591187, 0.35604858, 0.14132690, 0.11724854, 0.15853882, -0.24597168, 0.07019043,
|
|
0.02127075, 0.12658691, 0.06390381, -0.12292480, 0.15441895, -0.47640991, 0.06195068,
|
|
0.58981323, -0.15151978, -0.03604126, -0.45059204, -0.01672363, -0.46997070, 0.25750732,
|
|
0.18084717, 0.06661987, 0.13253784, 0.67828369, 0.11370850, 0.11325073, -0.04611206,
|
|
-0.07791138, -0.36544800, -0.06747437, -0.31594849, 0.16131592, 0.41983032, 0.11071777,
|
|
-0.36889648, 0.30963135, -0.37875366, 0.58508301, 0.00393677, 0.12338257, 0.03424072,
|
|
-0.21728516, -0.12838745, -0.46981812, 0.05868530, -0.25015259, 0.27407837, 0.65240479,
|
|
-0.34429932, -0.15179443, 0.14056396, 0.33505249, 0.28826904, 0.09921265, 0.34390259,
|
|
0.13656616, -0.23608398, 0.00863647, 0.02627563, -0.19119263, 0.19775391, -0.07214355,
|
|
0.07809448, 0.03454590, -0.03417969, 0.00033569, -0.23095703, 0.18673706, 0.05798340,
|
|
0.03814697, -0.04318237, 0.05487061, 0.08633423, 0.55950928, -0.06347656, 0.10333252,
|
|
0.25305176, 0.05853271, 0.12246704, -0.25543213, -0.34262085, -0.36437988, -0.21304321,
|
|
-0.05093384, 0.02777100, 0.07620239, -0.21215820, -0.09326172, 0.19021606, -0.40579224,
|
|
-0.01193237, 0.19845581, -0.35336304, -0.07397461, 0.20104980, 0.08615112, -0.44375610,
|
|
0.11419678, 0.24453735, -0.16555786, -0.05081177, -0.01406860, 0.27893066, -0.18692017,
|
|
0.07473755, 0.03451538, -0.39733887, 0.21548462, -0.22534180, -0.39651489, -0.04989624,
|
|
-0.57662964, 0.06390381, 0.62020874, -0.13470459, 0.04345703, -0.21862793, -0.02789307,
|
|
0.51696777, -0.27587891, 0.39004517, 0.09857178, -0.00738525, 0.31317139, 0.00048828,
|
|
-0.46572876, 0.29531860, -0.10009766, -0.27856445, 0.03594971, 0.25048828, -0.74584961,
|
|
-0.25350952, -0.03302002, 0.31188965, 0.01571655, 0.46710205, 0.21591187, 0.07260132,
|
|
-0.42132568, -0.53900146, -0.13674927, -0.16571045, -0.34454346, 0.12359619, -0.11184692,
|
|
0.00967407, 0.34576416, -0.05761719, 0.34848022, 0.17645264, -0.39395142, 0.10339355,
|
|
0.18215942, 0.20697021, 0.59109497, -0.11560059, -0.07385254, 0.10397339, 0.35437012,
|
|
-0.22863770, 0.01794434, 0.17559814, -0.17495728, 0.12142944, 0.10928345, -1.00000000,
|
|
-0.01379395, 0.21237183, -0.27035522, 0.27319336, -0.37066650, 0.41354370, -0.40054321,
|
|
0.00689697, 0.26321411, 0.39266968, 0.65298462, 0.41625977, -0.13909912, 0.78375244,
|
|
-0.30941772, 0.20169067, -0.39367676, 0.94021606, -0.24066162, 0.05557251, -0.24533081,
|
|
-0.05444336, -0.76754761, -0.19375610, -0.11041260, -0.17532349, 0.16006470, 0.02188110,
|
|
0.17465210, -0.04342651, -0.56777954, -0.40988159, 0.26687622, 0.11700439, -0.00344849,
|
|
-0.05395508, 0.37426758, -0.40719604, -0.15032959, -0.01660156, 0.04196167, -0.04559326,
|
|
-0.12969971, 0.12011719, 0.08419800, -0.11199951, 0.35174561, 0.10275269, -0.25686646,
|
|
0.48446655, 0.03225708, 0.28408813, -0.18701172, 0.36282349, -0.03280640, 0.32302856,
|
|
0.17233276, 0.48269653, 0.31112671, -0.04946899, 0.12774658, 0.52685547, 0.10211182,
|
|
0.05953979, 0.05999756, 0.20144653, 0.00744629, 0.27316284, 0.24377441, 0.39672852,
|
|
0.01702881, -0.35513306, 0.11364746, -0.13555908, 0.48880005, -0.15417480, -0.09149170,
|
|
-0.02615356, 0.46246338, -0.72250366, 0.22332764, 0.23849487, -0.25686646, -0.08514404,
|
|
-0.02062988, -0.34494019, -0.02297974, -0.80386353, -0.08074951, -0.12689209, -0.06896973,
|
|
0.24099731, -0.35650635, -0.09558105, 0.29254150, 0.23132324, -0.16726685, 0.00000000,
|
|
-0.24237061, 0.30899048, 0.29504395, -0.20898438, 0.17059326, -0.07672119, -0.14395142,
|
|
0.05572510, 0.20602417, -0.51550293, -0.03167725, -0.48840332, -0.20425415, 0.14144897,
|
|
0.07275391, -0.76669312, -0.22488403, 0.20651245, 0.03259277, 0.00085449, 0.03039551,
|
|
0.47555542, 0.38351440
|
|
};
|
|
|
|
/** Noise level table for power compensation.
|
|
* Equ: pow(2.0f, (double)(6 - i) / 3.0f) where i = 0...15 */
|
|
static const float pwc_levs[16] = {
|
|
3.96875, 3.15625, 2.5, 2.0, 1.59375, 1.25, 1.0, 0.78125,
|
|
0.625, 0.5, 0.40625, 0.3125, 0.25, 0.1875, 0.15625, 0.0
|
|
};
|
|
|
|
/** Map subband number to quant unit number. */
|
|
static const int subband_to_qu[17] = {
|
|
0, 8, 12, 16, 18, 20, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32
|
|
};
|
|
|
|
void ff_atrac3p_power_compensation(Atrac3pChanUnitCtx *ctx, AVFloatDSPContext *fdsp,
|
|
int ch_index, float *sp, int rng_index, int sb)
|
|
{
|
|
AtracGainInfo *g1, *g2;
|
|
LOCAL_ALIGNED_32(float, pwcsp, [ATRAC3P_SUBBAND_SAMPLES]);
|
|
float *dst, grp_lev, qu_lev;
|
|
int i, gain_lev, gcv = 0, qu, nsp;
|
|
int swap_ch = (ctx->unit_type == CH_UNIT_STEREO && ctx->swap_channels[sb]) ? 1 : 0;
|
|
|
|
if (ctx->channels[ch_index ^ swap_ch].power_levs[subband_to_powgrp[sb]] == ATRAC3P_POWER_COMP_OFF)
|
|
return;
|
|
|
|
/* generate initial noise spectrum */
|
|
for (i = 0; i < ATRAC3P_SUBBAND_SAMPLES; i++, rng_index++)
|
|
pwcsp[i] = noise_tab[rng_index & 0x3FF];
|
|
|
|
/* check gain control information */
|
|
g1 = &ctx->channels[ch_index ^ swap_ch].gain_data[sb];
|
|
g2 = &ctx->channels[ch_index ^ swap_ch].gain_data_prev[sb];
|
|
|
|
gain_lev = (g1->num_points > 0) ? (6 - g1->lev_code[0]) : 0;
|
|
|
|
for (i = 0; i < g2->num_points; i++)
|
|
gcv = FFMAX(gcv, gain_lev - (g2->lev_code[i] - 6));
|
|
|
|
for (i = 0; i < g1->num_points; i++)
|
|
gcv = FFMAX(gcv, 6 - g1->lev_code[i]);
|
|
|
|
grp_lev = pwc_levs[ctx->channels[ch_index ^ swap_ch].power_levs[subband_to_powgrp[sb]]] / (1 << gcv);
|
|
|
|
/* skip the lowest two quant units (frequencies 0...351 Hz) for subband 0 */
|
|
for (qu = subband_to_qu[sb] + (!sb ? 2 : 0); qu < subband_to_qu[sb + 1]; qu++) {
|
|
if (ctx->channels[ch_index].qu_wordlen[qu] <= 0)
|
|
continue;
|
|
|
|
qu_lev = ff_atrac3p_sf_tab[ctx->channels[ch_index].qu_sf_idx[qu]] *
|
|
ff_atrac3p_mant_tab[ctx->channels[ch_index].qu_wordlen[qu]] /
|
|
(1 << ctx->channels[ch_index].qu_wordlen[qu]) * grp_lev;
|
|
|
|
dst = &sp[ff_atrac3p_qu_to_spec_pos[qu]];
|
|
nsp = ff_atrac3p_qu_to_spec_pos[qu + 1] - ff_atrac3p_qu_to_spec_pos[qu];
|
|
|
|
fdsp->vector_fmac_scalar(dst, pwcsp, qu_lev, nsp);
|
|
}
|
|
}
|
|
|
|
void ff_atrac3p_imdct(AVFloatDSPContext *fdsp, FFTContext *mdct_ctx, float *pIn,
|
|
float *pOut, int wind_id, int sb)
|
|
{
|
|
int i;
|
|
|
|
if (sb & 1)
|
|
for (i = 0; i < ATRAC3P_SUBBAND_SAMPLES / 2; i++)
|
|
FFSWAP(float, pIn[i], pIn[ATRAC3P_SUBBAND_SAMPLES - 1 - i]);
|
|
|
|
mdct_ctx->imdct_calc(mdct_ctx, pOut, pIn);
|
|
|
|
/* Perform windowing on the output.
|
|
* ATRAC3+ uses two different MDCT windows:
|
|
* - The first one is just the plain sine window of size 256
|
|
* - The 2nd one is the plain sine window of size 128
|
|
* wrapped into zero (at the start) and one (at the end) regions.
|
|
* Both regions are 32 samples long. */
|
|
if (wind_id & 2) { /* 1st half: steep window */
|
|
memset(pOut, 0, sizeof(float) * 32);
|
|
fdsp->vector_fmul(&pOut[32], &pOut[32], ff_sine_64, 64);
|
|
} else /* 1st half: simple sine window */
|
|
fdsp->vector_fmul(pOut, pOut, ff_sine_128, ATRAC3P_MDCT_SIZE / 2);
|
|
|
|
if (wind_id & 1) { /* 2nd half: steep window */
|
|
fdsp->vector_fmul_reverse(&pOut[160], &pOut[160], ff_sine_64, 64);
|
|
memset(&pOut[224], 0, sizeof(float) * 32);
|
|
} else /* 2nd half: simple sine window */
|
|
fdsp->vector_fmul_reverse(&pOut[128], &pOut[128], ff_sine_128,
|
|
ATRAC3P_MDCT_SIZE / 2);
|
|
}
|
|
|
|
/* lookup table for fast modulo 23 op required for cyclic buffers of the IPQF */
|
|
static const int mod23_lut[26] = {
|
|
23, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11,
|
|
12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 0
|
|
};
|
|
|
|
/* First half of the 384-tap IPQF filtering coefficients. */
|
|
static const float ipqf_coeffs1[ATRAC3P_PQF_FIR_LEN][16] = {
|
|
{ -5.8336207e-7, -8.0604229e-7, -4.2005411e-7, -4.4400572e-8,
|
|
3.226247e-8, 3.530856e-8, 1.2660377e-8, 0.000010516783,
|
|
-0.000011838618, 6.005389e-7, 0.0000014333754, 0.0000023108685,
|
|
0.0000032569742, 0.0000046192422, 0.0000063894258, 0.0000070302972 },
|
|
{ -0.0000091622824, -0.000010502935, -0.0000079212787, -0.0000041712024,
|
|
-0.0000026336629, -0.0000015432918, -5.7168614e-7, 0.0000018111954,
|
|
0.000023530851, 0.00002780562, 0.000032302323, 0.000036968919,
|
|
0.000041575615, 0.000045337845, 0.000046043948, 0.000048585582 },
|
|
{ -0.000064464548, -0.000068306952, -0.000073081472, -0.00007612785,
|
|
-0.000074850752, -0.000070208509, -0.000062285151, -0.000058270442,
|
|
-0.000056296329, -0.000049888811, -0.000035615325, -0.000018532943,
|
|
0.0000016657353, 0.00002610587, 0.000053397067, 0.00008079566 },
|
|
{ -0.00054488552, -0.00052537228, -0.00049731287, -0.00045778,
|
|
-0.00040612387, -0.00034301577, -0.00026866337, -0.00018248901,
|
|
-0.000084307925, 0.000025081157, 0.00014135583, 0.00026649953,
|
|
0.00039945057, 0.00053928449, 0.00068422867, 0.00083093712 },
|
|
{ -0.0014771431, -0.001283227, -0.0010566821, -0.00079780724,
|
|
-0.00050782406, -0.00018855913, 0.00015771533, 0.00052769453,
|
|
0.00091862219, 0.001326357, 0.0017469483, 0.0021754825,
|
|
0.0026067684, 0.0030352892, 0.0034549395, 0.0038591374 },
|
|
{ -0.0022995141, -0.001443546, -0.00049266568, 0.00055068987,
|
|
0.001682895, 0.0028992873, 0.0041943151, 0.0055614738,
|
|
0.0069935122, 0.0084823566, 0.010018963, 0.011593862,
|
|
0.013196872, 0.014817309, 0.016444042, 0.018065533 },
|
|
{ -0.034426283, -0.034281436, -0.033992987, -0.033563249,
|
|
-0.032995768, -0.032295227, -0.031467363, -0.030518902,
|
|
-0.02945766, -0.028291954, -0.027031265, -0.025685543,
|
|
-0.024265358, -0.022781773, -0.021246184, -0.019670162 },
|
|
{ -0.0030586775, -0.0037203205, -0.0042847847, -0.0047529764,
|
|
-0.0051268316, -0.0054091476, -0.0056034233, -0.005714261,
|
|
-0.0057445862, -0.0057025906, -0.0055920109, -0.0054194843,
|
|
-0.0051914565, -0.0049146507, -0.0045959447, -0.0042418269 },
|
|
{ -0.0016376863, -0.0017651899, -0.0018608454, -0.0019252141,
|
|
-0.0019593791, -0.0019653172, -0.0019450618, -0.0018990048,
|
|
-0.00183808, -0.0017501717, -0.0016481078, -0.0015320742,
|
|
-0.0014046903, -0.0012685474, -0.001125814, -0.00097943726 },
|
|
{ -0.00055432378, -0.00055472925, -0.00054783461, -0.00053276919,
|
|
-0.00051135791, -0.00048466062, -0.00045358928, -0.00042499689,
|
|
-0.00036942671, -0.0003392619, -0.00030001783, -0.00025986304,
|
|
-0.0002197204, -0.00018116167, -0.00014691355, -0.00011279432 },
|
|
{ -0.000064147389, -0.00006174868, -0.000054267788, -0.000047133824,
|
|
-0.000042927582, -0.000039477309, -0.000036340745, -0.000029687517,
|
|
-0.000049787737, -0.000041577889, -0.000033864744, -0.000026534748,
|
|
-0.000019841305, -0.000014789486, -0.000013131184, -0.0000099198869 },
|
|
{ -0.0000062990207, -0.0000072701259, -0.000011984052, -0.000017348082,
|
|
-0.000019907106, -0.000021348773, -0.000021961965, -0.000012203576,
|
|
-0.000010840992, 4.6299544e-7, 5.2588763e-7, 2.7792686e-7,
|
|
-2.3649704e-7, -0.0000010897784, -9.171448e-7, -5.22682e-7 }
|
|
};
|
|
|
|
/* Second half of the 384-tap IPQF filtering coefficients. */
|
|
static const float ipqf_coeffs2[ATRAC3P_PQF_FIR_LEN][16] = {
|
|
{ 5.22682e-7, 9.171448e-7, 0.0000010897784, 2.3649704e-7,
|
|
-2.7792686e-7, -5.2588763e-7, -4.6299544e-7, 0.000010840992,
|
|
-0.000012203576, -0.000021961965, -0.000021348773, -0.000019907106,
|
|
-0.000017348082, -0.000011984052, -0.0000072701259, -0.0000062990207 },
|
|
{ 0.0000099198869, 0.000013131184, 0.000014789486, 0.000019841305,
|
|
0.000026534748, 0.000033864744, 0.000041577889, 0.000049787737,
|
|
-0.000029687517, -0.000036340745, -0.000039477309, -0.000042927582,
|
|
-0.000047133824, -0.000054267788, -0.00006174868, -0.000064147389 },
|
|
{ 0.00011279432, 0.00014691355, 0.00018116167, 0.0002197204,
|
|
0.00025986304, 0.00030001783, 0.0003392619, 0.00036942671,
|
|
-0.00042499689, -0.00045358928, -0.00048466062, -0.00051135791,
|
|
-0.00053276919, -0.00054783461, -0.00055472925, -0.00055432378 },
|
|
{ 0.00097943726, 0.001125814, 0.0012685474, 0.0014046903,
|
|
0.0015320742, 0.0016481078, 0.0017501717, 0.00183808,
|
|
-0.0018990048, -0.0019450618, -0.0019653172, -0.0019593791,
|
|
-0.0019252141, -0.0018608454, -0.0017651899, -0.0016376863 },
|
|
{ 0.0042418269, 0.0045959447, 0.0049146507, 0.0051914565,
|
|
0.0054194843, 0.0055920109, 0.0057025906, 0.0057445862,
|
|
-0.005714261, -0.0056034233, -0.0054091476, -0.0051268316,
|
|
-0.0047529764, -0.0042847847, -0.0037203205, -0.0030586775 },
|
|
{ 0.019670162, 0.021246184, 0.022781773, 0.024265358,
|
|
0.025685543, 0.027031265, 0.028291954, 0.02945766,
|
|
-0.030518902, -0.031467363, -0.032295227, -0.032995768,
|
|
-0.033563249, -0.033992987, -0.034281436, -0.034426283 },
|
|
{ -0.018065533, -0.016444042, -0.014817309, -0.013196872,
|
|
-0.011593862, -0.010018963, -0.0084823566, -0.0069935122,
|
|
0.0055614738, 0.0041943151, 0.0028992873, 0.001682895,
|
|
0.00055068987, -0.00049266568, -0.001443546, -0.0022995141 },
|
|
{ -0.0038591374, -0.0034549395, -0.0030352892, -0.0026067684,
|
|
-0.0021754825, -0.0017469483, -0.001326357, -0.00091862219,
|
|
0.00052769453, 0.00015771533, -0.00018855913, -0.00050782406,
|
|
-0.00079780724, -0.0010566821, -0.001283227, -0.0014771431 },
|
|
{ -0.00083093712, -0.00068422867, -0.00053928449, -0.00039945057,
|
|
-0.00026649953, -0.00014135583, -0.000025081157, 0.000084307925,
|
|
-0.00018248901, -0.00026866337, -0.00034301577, -0.00040612387,
|
|
-0.00045778, -0.00049731287, -0.00052537228, -0.00054488552 },
|
|
{ -0.00008079566, -0.000053397067, -0.00002610587, -0.0000016657353,
|
|
0.000018532943, 0.000035615325, 0.000049888811, 0.000056296329,
|
|
-0.000058270442, -0.000062285151, -0.000070208509, -0.000074850752,
|
|
-0.00007612785, -0.000073081472, -0.000068306952, -0.000064464548 },
|
|
{ -0.000048585582, -0.000046043948, -0.000045337845, -0.000041575615,
|
|
-0.000036968919, -0.000032302323, -0.00002780562, -0.000023530851,
|
|
0.0000018111954, -5.7168614e-7, -0.0000015432918, -0.0000026336629,
|
|
-0.0000041712024, -0.0000079212787, -0.000010502935, -0.0000091622824 },
|
|
{ -0.0000070302972, -0.0000063894258, -0.0000046192422, -0.0000032569742,
|
|
-0.0000023108685, -0.0000014333754, -6.005389e-7, 0.000011838618,
|
|
0.000010516783, 1.2660377e-8, 3.530856e-8, 3.226247e-8,
|
|
-4.4400572e-8, -4.2005411e-7, -8.0604229e-7, -5.8336207e-7 }
|
|
};
|
|
|
|
void ff_atrac3p_ipqf(FFTContext *dct_ctx, Atrac3pIPQFChannelCtx *hist,
|
|
const float *in, float *out)
|
|
{
|
|
int i, s, sb, t, pos_now, pos_next;
|
|
LOCAL_ALIGNED(32, float, idct_in, [ATRAC3P_SUBBANDS]);
|
|
LOCAL_ALIGNED(32, float, idct_out, [ATRAC3P_SUBBANDS]);
|
|
|
|
memset(out, 0, ATRAC3P_FRAME_SAMPLES * sizeof(*out));
|
|
|
|
for (s = 0; s < ATRAC3P_SUBBAND_SAMPLES; s++) {
|
|
/* pick up one sample from each subband */
|
|
for (sb = 0; sb < ATRAC3P_SUBBANDS; sb++)
|
|
idct_in[sb] = in[sb * ATRAC3P_SUBBAND_SAMPLES + s];
|
|
|
|
/* Calculate the sine and cosine part of the PQF using IDCT-IV */
|
|
dct_ctx->imdct_half(dct_ctx, idct_out, idct_in);
|
|
|
|
/* append the result to the history */
|
|
for (i = 0; i < 8; i++) {
|
|
hist->buf1[hist->pos][i] = idct_out[i + 8];
|
|
hist->buf2[hist->pos][i] = idct_out[7 - i];
|
|
}
|
|
|
|
pos_now = hist->pos;
|
|
pos_next = mod23_lut[pos_now + 2]; // pos_next = (pos_now + 1) % 23;
|
|
|
|
for (t = 0; t < ATRAC3P_PQF_FIR_LEN; t++) {
|
|
for (i = 0; i < 8; i++) {
|
|
out[s * 16 + i + 0] += hist->buf1[pos_now][i] * ipqf_coeffs1[t][i] +
|
|
hist->buf2[pos_next][i] * ipqf_coeffs2[t][i];
|
|
out[s * 16 + i + 8] += hist->buf1[pos_now][7 - i] * ipqf_coeffs1[t][i + 8] +
|
|
hist->buf2[pos_next][7 - i] * ipqf_coeffs2[t][i + 8];
|
|
}
|
|
|
|
pos_now = mod23_lut[pos_next + 2]; // pos_now = (pos_now + 2) % 23;
|
|
pos_next = mod23_lut[pos_now + 2]; // pos_next = (pos_next + 2) % 23;
|
|
}
|
|
|
|
hist->pos = mod23_lut[hist->pos]; // hist->pos = (hist->pos - 1) % 23;
|
|
}
|
|
}
|