| /* |
| * AAC Spectral Band Replication decoding functions |
| * Copyright (c) 2008-2009 Robert Swain ( rob opendot cl ) |
| * Copyright (c) 2009-2010 Alex Converse <alex.converse@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 |
| */ |
| |
| /** |
| * @file |
| * AAC Spectral Band Replication decoding functions |
| * @author Robert Swain ( rob opendot cl ) |
| */ |
| #define USE_FIXED 0 |
| |
| #include "aac.h" |
| #include "sbr.h" |
| #include "aacsbr.h" |
| #include "aacsbrdata.h" |
| #include "aacsbr_tablegen.h" |
| #include "fft.h" |
| #include "internal.h" |
| #include "aacps.h" |
| #include "sbrdsp.h" |
| #include "libavutil/internal.h" |
| #include "libavutil/libm.h" |
| #include "libavutil/avassert.h" |
| |
| #include <stdint.h> |
| #include <float.h> |
| #include <math.h> |
| |
| #if ARCH_MIPS |
| #include "mips/aacsbr_mips.h" |
| #endif /* ARCH_MIPS */ |
| |
| static VLC vlc_sbr[10]; |
| static void aacsbr_func_ptr_init(AACSBRContext *c); |
| |
| static void make_bands(int16_t* bands, int start, int stop, int num_bands) |
| { |
| int k, previous, present; |
| float base, prod; |
| |
| base = powf((float)stop / start, 1.0f / num_bands); |
| prod = start; |
| previous = start; |
| |
| for (k = 0; k < num_bands-1; k++) { |
| prod *= base; |
| present = lrintf(prod); |
| bands[k] = present - previous; |
| previous = present; |
| } |
| bands[num_bands-1] = stop - previous; |
| } |
| |
| /// Dequantization and stereo decoding (14496-3 sp04 p203) |
| static void sbr_dequant(SpectralBandReplication *sbr, int id_aac) |
| { |
| int k, e; |
| int ch; |
| static const double exp2_tab[2] = {1, M_SQRT2}; |
| if (id_aac == TYPE_CPE && sbr->bs_coupling) { |
| int pan_offset = sbr->data[0].bs_amp_res ? 12 : 24; |
| for (e = 1; e <= sbr->data[0].bs_num_env; e++) { |
| for (k = 0; k < sbr->n[sbr->data[0].bs_freq_res[e]]; k++) { |
| float temp1, temp2, fac; |
| if (sbr->data[0].bs_amp_res) { |
| temp1 = ff_exp2fi(sbr->data[0].env_facs_q[e][k] + 7); |
| temp2 = ff_exp2fi(pan_offset - sbr->data[1].env_facs_q[e][k]); |
| } |
| else { |
| temp1 = ff_exp2fi((sbr->data[0].env_facs_q[e][k]>>1) + 7) * |
| exp2_tab[sbr->data[0].env_facs_q[e][k] & 1]; |
| temp2 = ff_exp2fi((pan_offset - sbr->data[1].env_facs_q[e][k])>>1) * |
| exp2_tab[(pan_offset - sbr->data[1].env_facs_q[e][k]) & 1]; |
| } |
| if (temp1 > 1E20) { |
| av_log(NULL, AV_LOG_ERROR, "envelope scalefactor overflow in dequant\n"); |
| temp1 = 1; |
| } |
| fac = temp1 / (1.0f + temp2); |
| sbr->data[0].env_facs[e][k] = fac; |
| sbr->data[1].env_facs[e][k] = fac * temp2; |
| } |
| } |
| for (e = 1; e <= sbr->data[0].bs_num_noise; e++) { |
| for (k = 0; k < sbr->n_q; k++) { |
| float temp1 = ff_exp2fi(NOISE_FLOOR_OFFSET - sbr->data[0].noise_facs_q[e][k] + 1); |
| float temp2 = ff_exp2fi(12 - sbr->data[1].noise_facs_q[e][k]); |
| float fac; |
| av_assert0(temp1 <= 1E20); |
| fac = temp1 / (1.0f + temp2); |
| sbr->data[0].noise_facs[e][k] = fac; |
| sbr->data[1].noise_facs[e][k] = fac * temp2; |
| } |
| } |
| } else { // SCE or one non-coupled CPE |
| for (ch = 0; ch < (id_aac == TYPE_CPE) + 1; ch++) { |
| for (e = 1; e <= sbr->data[ch].bs_num_env; e++) |
| for (k = 0; k < sbr->n[sbr->data[ch].bs_freq_res[e]]; k++){ |
| if (sbr->data[ch].bs_amp_res) |
| sbr->data[ch].env_facs[e][k] = ff_exp2fi(sbr->data[ch].env_facs_q[e][k] + 6); |
| else |
| sbr->data[ch].env_facs[e][k] = ff_exp2fi((sbr->data[ch].env_facs_q[e][k]>>1) + 6) |
| * exp2_tab[sbr->data[ch].env_facs_q[e][k] & 1]; |
| if (sbr->data[ch].env_facs[e][k] > 1E20) { |
| av_log(NULL, AV_LOG_ERROR, "envelope scalefactor overflow in dequant\n"); |
| sbr->data[ch].env_facs[e][k] = 1; |
| } |
| } |
| |
| for (e = 1; e <= sbr->data[ch].bs_num_noise; e++) |
| for (k = 0; k < sbr->n_q; k++) |
| sbr->data[ch].noise_facs[e][k] = |
| ff_exp2fi(NOISE_FLOOR_OFFSET - sbr->data[ch].noise_facs_q[e][k]); |
| } |
| } |
| } |
| |
| /** High Frequency Generation (14496-3 sp04 p214+) and Inverse Filtering |
| * (14496-3 sp04 p214) |
| * Warning: This routine does not seem numerically stable. |
| */ |
| static void sbr_hf_inverse_filter(SBRDSPContext *dsp, |
| float (*alpha0)[2], float (*alpha1)[2], |
| const float X_low[32][40][2], int k0) |
| { |
| int k; |
| for (k = 0; k < k0; k++) { |
| LOCAL_ALIGNED_16(float, phi, [3], [2][2]); |
| float dk; |
| |
| dsp->autocorrelate(X_low[k], phi); |
| |
| dk = phi[2][1][0] * phi[1][0][0] - |
| (phi[1][1][0] * phi[1][1][0] + phi[1][1][1] * phi[1][1][1]) / 1.000001f; |
| |
| if (!dk) { |
| alpha1[k][0] = 0; |
| alpha1[k][1] = 0; |
| } else { |
| float temp_real, temp_im; |
| temp_real = phi[0][0][0] * phi[1][1][0] - |
| phi[0][0][1] * phi[1][1][1] - |
| phi[0][1][0] * phi[1][0][0]; |
| temp_im = phi[0][0][0] * phi[1][1][1] + |
| phi[0][0][1] * phi[1][1][0] - |
| phi[0][1][1] * phi[1][0][0]; |
| |
| alpha1[k][0] = temp_real / dk; |
| alpha1[k][1] = temp_im / dk; |
| } |
| |
| if (!phi[1][0][0]) { |
| alpha0[k][0] = 0; |
| alpha0[k][1] = 0; |
| } else { |
| float temp_real, temp_im; |
| temp_real = phi[0][0][0] + alpha1[k][0] * phi[1][1][0] + |
| alpha1[k][1] * phi[1][1][1]; |
| temp_im = phi[0][0][1] + alpha1[k][1] * phi[1][1][0] - |
| alpha1[k][0] * phi[1][1][1]; |
| |
| alpha0[k][0] = -temp_real / phi[1][0][0]; |
| alpha0[k][1] = -temp_im / phi[1][0][0]; |
| } |
| |
| if (alpha1[k][0] * alpha1[k][0] + alpha1[k][1] * alpha1[k][1] >= 16.0f || |
| alpha0[k][0] * alpha0[k][0] + alpha0[k][1] * alpha0[k][1] >= 16.0f) { |
| alpha1[k][0] = 0; |
| alpha1[k][1] = 0; |
| alpha0[k][0] = 0; |
| alpha0[k][1] = 0; |
| } |
| } |
| } |
| |
| /// Chirp Factors (14496-3 sp04 p214) |
| static void sbr_chirp(SpectralBandReplication *sbr, SBRData *ch_data) |
| { |
| int i; |
| float new_bw; |
| static const float bw_tab[] = { 0.0f, 0.75f, 0.9f, 0.98f }; |
| |
| for (i = 0; i < sbr->n_q; i++) { |
| if (ch_data->bs_invf_mode[0][i] + ch_data->bs_invf_mode[1][i] == 1) { |
| new_bw = 0.6f; |
| } else |
| new_bw = bw_tab[ch_data->bs_invf_mode[0][i]]; |
| |
| if (new_bw < ch_data->bw_array[i]) { |
| new_bw = 0.75f * new_bw + 0.25f * ch_data->bw_array[i]; |
| } else |
| new_bw = 0.90625f * new_bw + 0.09375f * ch_data->bw_array[i]; |
| ch_data->bw_array[i] = new_bw < 0.015625f ? 0.0f : new_bw; |
| } |
| } |
| |
| /** |
| * Calculation of levels of additional HF signal components (14496-3 sp04 p219) |
| * and Calculation of gain (14496-3 sp04 p219) |
| */ |
| static void sbr_gain_calc(AACContext *ac, SpectralBandReplication *sbr, |
| SBRData *ch_data, const int e_a[2]) |
| { |
| int e, k, m; |
| // max gain limits : -3dB, 0dB, 3dB, inf dB (limiter off) |
| static const float limgain[4] = { 0.70795, 1.0, 1.41254, 10000000000 }; |
| |
| for (e = 0; e < ch_data->bs_num_env; e++) { |
| int delta = !((e == e_a[1]) || (e == e_a[0])); |
| for (k = 0; k < sbr->n_lim; k++) { |
| float gain_boost, gain_max; |
| float sum[2] = { 0.0f, 0.0f }; |
| for (m = sbr->f_tablelim[k] - sbr->kx[1]; m < sbr->f_tablelim[k + 1] - sbr->kx[1]; m++) { |
| const float temp = sbr->e_origmapped[e][m] / (1.0f + sbr->q_mapped[e][m]); |
| sbr->q_m[e][m] = sqrtf(temp * sbr->q_mapped[e][m]); |
| sbr->s_m[e][m] = sqrtf(temp * ch_data->s_indexmapped[e + 1][m]); |
| if (!sbr->s_mapped[e][m]) { |
| sbr->gain[e][m] = sqrtf(sbr->e_origmapped[e][m] / |
| ((1.0f + sbr->e_curr[e][m]) * |
| (1.0f + sbr->q_mapped[e][m] * delta))); |
| } else { |
| sbr->gain[e][m] = sqrtf(sbr->e_origmapped[e][m] * sbr->q_mapped[e][m] / |
| ((1.0f + sbr->e_curr[e][m]) * |
| (1.0f + sbr->q_mapped[e][m]))); |
| } |
| sbr->gain[e][m] += FLT_MIN; |
| } |
| for (m = sbr->f_tablelim[k] - sbr->kx[1]; m < sbr->f_tablelim[k + 1] - sbr->kx[1]; m++) { |
| sum[0] += sbr->e_origmapped[e][m]; |
| sum[1] += sbr->e_curr[e][m]; |
| } |
| gain_max = limgain[sbr->bs_limiter_gains] * sqrtf((FLT_EPSILON + sum[0]) / (FLT_EPSILON + sum[1])); |
| gain_max = FFMIN(100000.f, gain_max); |
| for (m = sbr->f_tablelim[k] - sbr->kx[1]; m < sbr->f_tablelim[k + 1] - sbr->kx[1]; m++) { |
| float q_m_max = sbr->q_m[e][m] * gain_max / sbr->gain[e][m]; |
| sbr->q_m[e][m] = FFMIN(sbr->q_m[e][m], q_m_max); |
| sbr->gain[e][m] = FFMIN(sbr->gain[e][m], gain_max); |
| } |
| sum[0] = sum[1] = 0.0f; |
| for (m = sbr->f_tablelim[k] - sbr->kx[1]; m < sbr->f_tablelim[k + 1] - sbr->kx[1]; m++) { |
| sum[0] += sbr->e_origmapped[e][m]; |
| sum[1] += sbr->e_curr[e][m] * sbr->gain[e][m] * sbr->gain[e][m] |
| + sbr->s_m[e][m] * sbr->s_m[e][m] |
| + (delta && !sbr->s_m[e][m]) * sbr->q_m[e][m] * sbr->q_m[e][m]; |
| } |
| gain_boost = sqrtf((FLT_EPSILON + sum[0]) / (FLT_EPSILON + sum[1])); |
| gain_boost = FFMIN(1.584893192f, gain_boost); |
| for (m = sbr->f_tablelim[k] - sbr->kx[1]; m < sbr->f_tablelim[k + 1] - sbr->kx[1]; m++) { |
| sbr->gain[e][m] *= gain_boost; |
| sbr->q_m[e][m] *= gain_boost; |
| sbr->s_m[e][m] *= gain_boost; |
| } |
| } |
| } |
| } |
| |
| /// Assembling HF Signals (14496-3 sp04 p220) |
| static void sbr_hf_assemble(float Y1[38][64][2], |
| const float X_high[64][40][2], |
| SpectralBandReplication *sbr, SBRData *ch_data, |
| const int e_a[2]) |
| { |
| int e, i, j, m; |
| const int h_SL = 4 * !sbr->bs_smoothing_mode; |
| const int kx = sbr->kx[1]; |
| const int m_max = sbr->m[1]; |
| static const float h_smooth[5] = { |
| 0.33333333333333, |
| 0.30150283239582, |
| 0.21816949906249, |
| 0.11516383427084, |
| 0.03183050093751, |
| }; |
| float (*g_temp)[48] = ch_data->g_temp, (*q_temp)[48] = ch_data->q_temp; |
| int indexnoise = ch_data->f_indexnoise; |
| int indexsine = ch_data->f_indexsine; |
| |
| if (sbr->reset) { |
| for (i = 0; i < h_SL; i++) { |
| memcpy(g_temp[i + 2*ch_data->t_env[0]], sbr->gain[0], m_max * sizeof(sbr->gain[0][0])); |
| memcpy(q_temp[i + 2*ch_data->t_env[0]], sbr->q_m[0], m_max * sizeof(sbr->q_m[0][0])); |
| } |
| } else if (h_SL) { |
| for (i = 0; i < 4; i++) { |
| memcpy(g_temp[i + 2 * ch_data->t_env[0]], |
| g_temp[i + 2 * ch_data->t_env_num_env_old], |
| sizeof(g_temp[0])); |
| memcpy(q_temp[i + 2 * ch_data->t_env[0]], |
| q_temp[i + 2 * ch_data->t_env_num_env_old], |
| sizeof(q_temp[0])); |
| } |
| } |
| |
| for (e = 0; e < ch_data->bs_num_env; e++) { |
| for (i = 2 * ch_data->t_env[e]; i < 2 * ch_data->t_env[e + 1]; i++) { |
| memcpy(g_temp[h_SL + i], sbr->gain[e], m_max * sizeof(sbr->gain[0][0])); |
| memcpy(q_temp[h_SL + i], sbr->q_m[e], m_max * sizeof(sbr->q_m[0][0])); |
| } |
| } |
| |
| for (e = 0; e < ch_data->bs_num_env; e++) { |
| for (i = 2 * ch_data->t_env[e]; i < 2 * ch_data->t_env[e + 1]; i++) { |
| LOCAL_ALIGNED_16(float, g_filt_tab, [48]); |
| LOCAL_ALIGNED_16(float, q_filt_tab, [48]); |
| float *g_filt, *q_filt; |
| |
| if (h_SL && e != e_a[0] && e != e_a[1]) { |
| g_filt = g_filt_tab; |
| q_filt = q_filt_tab; |
| for (m = 0; m < m_max; m++) { |
| const int idx1 = i + h_SL; |
| g_filt[m] = 0.0f; |
| q_filt[m] = 0.0f; |
| for (j = 0; j <= h_SL; j++) { |
| g_filt[m] += g_temp[idx1 - j][m] * h_smooth[j]; |
| q_filt[m] += q_temp[idx1 - j][m] * h_smooth[j]; |
| } |
| } |
| } else { |
| g_filt = g_temp[i + h_SL]; |
| q_filt = q_temp[i]; |
| } |
| |
| sbr->dsp.hf_g_filt(Y1[i] + kx, X_high + kx, g_filt, m_max, |
| i + ENVELOPE_ADJUSTMENT_OFFSET); |
| |
| if (e != e_a[0] && e != e_a[1]) { |
| sbr->dsp.hf_apply_noise[indexsine](Y1[i] + kx, sbr->s_m[e], |
| q_filt, indexnoise, |
| kx, m_max); |
| } else { |
| int idx = indexsine&1; |
| int A = (1-((indexsine+(kx & 1))&2)); |
| int B = (A^(-idx)) + idx; |
| float *out = &Y1[i][kx][idx]; |
| float *in = sbr->s_m[e]; |
| for (m = 0; m+1 < m_max; m+=2) { |
| out[2*m ] += in[m ] * A; |
| out[2*m+2] += in[m+1] * B; |
| } |
| if(m_max&1) |
| out[2*m ] += in[m ] * A; |
| } |
| indexnoise = (indexnoise + m_max) & 0x1ff; |
| indexsine = (indexsine + 1) & 3; |
| } |
| } |
| ch_data->f_indexnoise = indexnoise; |
| ch_data->f_indexsine = indexsine; |
| } |
| |
| #include "aacsbr_template.c" |
