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964 lines
40 KiB
964 lines
40 KiB
/* |
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* AAC coefficients encoder |
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* Copyright (C) 2008-2009 Konstantin Shishkov |
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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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/** |
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* @file |
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* AAC coefficients encoder |
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*/ |
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/*********************************** |
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* TODOs: |
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* speedup quantizer selection |
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* add sane pulse detection |
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***********************************/ |
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#include "libavutil/libm.h" // brought forward to work around cygwin header breakage |
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#include <float.h> |
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#include "libavutil/mathematics.h" |
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#include "mathops.h" |
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#include "avcodec.h" |
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#include "put_bits.h" |
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#include "aac.h" |
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#include "aacenc.h" |
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#include "aactab.h" |
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#include "aacenctab.h" |
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#include "aacenc_utils.h" |
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#include "aacenc_quantization.h" |
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#include "aacenc_is.h" |
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#include "aacenc_tns.h" |
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#include "aacenc_ltp.h" |
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#include "aacenc_pred.h" |
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#include "libavcodec/aaccoder_twoloop.h" |
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/* Parameter of f(x) = a*(lambda/100), defines the maximum fourier spread |
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* beyond which no PNS is used (since the SFBs contain tone rather than noise) */ |
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#define NOISE_SPREAD_THRESHOLD 0.9f |
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/* Parameter of f(x) = a*(100/lambda), defines how much PNS is allowed to |
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* replace low energy non zero bands */ |
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#define NOISE_LAMBDA_REPLACE 1.948f |
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#include "libavcodec/aaccoder_trellis.h" |
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|
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/** |
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* structure used in optimal codebook search |
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*/ |
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typedef struct BandCodingPath { |
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int prev_idx; ///< pointer to the previous path point |
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float cost; ///< path cost |
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int run; |
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} BandCodingPath; |
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/** |
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* Encode band info for single window group bands. |
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*/ |
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static void encode_window_bands_info(AACEncContext *s, SingleChannelElement *sce, |
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int win, int group_len, const float lambda) |
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{ |
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BandCodingPath path[120][CB_TOT_ALL]; |
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int w, swb, cb, start, size; |
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int i, j; |
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const int max_sfb = sce->ics.max_sfb; |
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const int run_bits = sce->ics.num_windows == 1 ? 5 : 3; |
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const int run_esc = (1 << run_bits) - 1; |
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int idx, ppos, count; |
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int stackrun[120], stackcb[120], stack_len; |
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float next_minrd = INFINITY; |
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int next_mincb = 0; |
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s->abs_pow34(s->scoefs, sce->coeffs, 1024); |
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start = win*128; |
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for (cb = 0; cb < CB_TOT_ALL; cb++) { |
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path[0][cb].cost = 0.0f; |
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path[0][cb].prev_idx = -1; |
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path[0][cb].run = 0; |
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} |
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for (swb = 0; swb < max_sfb; swb++) { |
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size = sce->ics.swb_sizes[swb]; |
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if (sce->zeroes[win*16 + swb]) { |
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for (cb = 0; cb < CB_TOT_ALL; cb++) { |
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path[swb+1][cb].prev_idx = cb; |
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path[swb+1][cb].cost = path[swb][cb].cost; |
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path[swb+1][cb].run = path[swb][cb].run + 1; |
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} |
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} else { |
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float minrd = next_minrd; |
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int mincb = next_mincb; |
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next_minrd = INFINITY; |
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next_mincb = 0; |
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for (cb = 0; cb < CB_TOT_ALL; cb++) { |
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float cost_stay_here, cost_get_here; |
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float rd = 0.0f; |
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if (cb >= 12 && sce->band_type[win*16+swb] < aac_cb_out_map[cb] || |
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cb < aac_cb_in_map[sce->band_type[win*16+swb]] && sce->band_type[win*16+swb] > aac_cb_out_map[cb]) { |
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path[swb+1][cb].prev_idx = -1; |
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path[swb+1][cb].cost = INFINITY; |
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path[swb+1][cb].run = path[swb][cb].run + 1; |
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continue; |
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} |
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for (w = 0; w < group_len; w++) { |
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FFPsyBand *band = &s->psy.ch[s->cur_channel].psy_bands[(win+w)*16+swb]; |
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rd += quantize_band_cost(s, &sce->coeffs[start + w*128], |
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&s->scoefs[start + w*128], size, |
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sce->sf_idx[(win+w)*16+swb], aac_cb_out_map[cb], |
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lambda / band->threshold, INFINITY, NULL, NULL, 0); |
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} |
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cost_stay_here = path[swb][cb].cost + rd; |
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cost_get_here = minrd + rd + run_bits + 4; |
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if ( run_value_bits[sce->ics.num_windows == 8][path[swb][cb].run] |
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!= run_value_bits[sce->ics.num_windows == 8][path[swb][cb].run+1]) |
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cost_stay_here += run_bits; |
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if (cost_get_here < cost_stay_here) { |
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path[swb+1][cb].prev_idx = mincb; |
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path[swb+1][cb].cost = cost_get_here; |
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path[swb+1][cb].run = 1; |
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} else { |
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path[swb+1][cb].prev_idx = cb; |
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path[swb+1][cb].cost = cost_stay_here; |
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path[swb+1][cb].run = path[swb][cb].run + 1; |
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} |
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if (path[swb+1][cb].cost < next_minrd) { |
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next_minrd = path[swb+1][cb].cost; |
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next_mincb = cb; |
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} |
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} |
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} |
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start += sce->ics.swb_sizes[swb]; |
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} |
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//convert resulting path from backward-linked list |
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stack_len = 0; |
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idx = 0; |
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for (cb = 1; cb < CB_TOT_ALL; cb++) |
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if (path[max_sfb][cb].cost < path[max_sfb][idx].cost) |
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idx = cb; |
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ppos = max_sfb; |
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while (ppos > 0) { |
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av_assert1(idx >= 0); |
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cb = idx; |
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stackrun[stack_len] = path[ppos][cb].run; |
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stackcb [stack_len] = cb; |
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idx = path[ppos-path[ppos][cb].run+1][cb].prev_idx; |
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ppos -= path[ppos][cb].run; |
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stack_len++; |
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} |
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//perform actual band info encoding |
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start = 0; |
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for (i = stack_len - 1; i >= 0; i--) { |
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cb = aac_cb_out_map[stackcb[i]]; |
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put_bits(&s->pb, 4, cb); |
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count = stackrun[i]; |
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memset(sce->zeroes + win*16 + start, !cb, count); |
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//XXX: memset when band_type is also uint8_t |
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for (j = 0; j < count; j++) { |
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sce->band_type[win*16 + start] = cb; |
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start++; |
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} |
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while (count >= run_esc) { |
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put_bits(&s->pb, run_bits, run_esc); |
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count -= run_esc; |
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} |
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put_bits(&s->pb, run_bits, count); |
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} |
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} |
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typedef struct TrellisPath { |
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float cost; |
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int prev; |
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} TrellisPath; |
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#define TRELLIS_STAGES 121 |
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#define TRELLIS_STATES (SCALE_MAX_DIFF+1) |
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static void set_special_band_scalefactors(AACEncContext *s, SingleChannelElement *sce) |
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{ |
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int w, g; |
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int prevscaler_n = -255, prevscaler_i = 0; |
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int bands = 0; |
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for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) { |
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for (g = 0; g < sce->ics.num_swb; g++) { |
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if (sce->zeroes[w*16+g]) |
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continue; |
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if (sce->band_type[w*16+g] == INTENSITY_BT || sce->band_type[w*16+g] == INTENSITY_BT2) { |
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sce->sf_idx[w*16+g] = av_clip(roundf(log2f(sce->is_ener[w*16+g])*2), -155, 100); |
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bands++; |
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} else if (sce->band_type[w*16+g] == NOISE_BT) { |
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sce->sf_idx[w*16+g] = av_clip(3+ceilf(log2f(sce->pns_ener[w*16+g])*2), -100, 155); |
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if (prevscaler_n == -255) |
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prevscaler_n = sce->sf_idx[w*16+g]; |
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bands++; |
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} |
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} |
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} |
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if (!bands) |
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return; |
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/* Clip the scalefactor indices */ |
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for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) { |
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for (g = 0; g < sce->ics.num_swb; g++) { |
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if (sce->zeroes[w*16+g]) |
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continue; |
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if (sce->band_type[w*16+g] == INTENSITY_BT || sce->band_type[w*16+g] == INTENSITY_BT2) { |
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sce->sf_idx[w*16+g] = prevscaler_i = av_clip(sce->sf_idx[w*16+g], prevscaler_i - SCALE_MAX_DIFF, prevscaler_i + SCALE_MAX_DIFF); |
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} else if (sce->band_type[w*16+g] == NOISE_BT) { |
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sce->sf_idx[w*16+g] = prevscaler_n = av_clip(sce->sf_idx[w*16+g], prevscaler_n - SCALE_MAX_DIFF, prevscaler_n + SCALE_MAX_DIFF); |
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} |
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} |
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} |
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} |
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static void search_for_quantizers_anmr(AVCodecContext *avctx, AACEncContext *s, |
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SingleChannelElement *sce, |
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const float lambda) |
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{ |
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int q, w, w2, g, start = 0; |
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int i, j; |
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int idx; |
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TrellisPath paths[TRELLIS_STAGES][TRELLIS_STATES]; |
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int bandaddr[TRELLIS_STAGES]; |
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int minq; |
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float mincost; |
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float q0f = FLT_MAX, q1f = 0.0f, qnrgf = 0.0f; |
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int q0, q1, qcnt = 0; |
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for (i = 0; i < 1024; i++) { |
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float t = fabsf(sce->coeffs[i]); |
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if (t > 0.0f) { |
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q0f = FFMIN(q0f, t); |
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q1f = FFMAX(q1f, t); |
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qnrgf += t*t; |
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qcnt++; |
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} |
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} |
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if (!qcnt) { |
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memset(sce->sf_idx, 0, sizeof(sce->sf_idx)); |
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memset(sce->zeroes, 1, sizeof(sce->zeroes)); |
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return; |
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} |
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//minimum scalefactor index is when minimum nonzero coefficient after quantizing is not clipped |
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q0 = av_clip(coef2minsf(q0f), 0, SCALE_MAX_POS-1); |
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//maximum scalefactor index is when maximum coefficient after quantizing is still not zero |
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q1 = av_clip(coef2maxsf(q1f), 1, SCALE_MAX_POS); |
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if (q1 - q0 > 60) { |
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int q0low = q0; |
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int q1high = q1; |
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//minimum scalefactor index is when maximum nonzero coefficient after quantizing is not clipped |
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int qnrg = av_clip_uint8(log2f(sqrtf(qnrgf/qcnt))*4 - 31 + SCALE_ONE_POS - SCALE_DIV_512); |
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q1 = qnrg + 30; |
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q0 = qnrg - 30; |
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if (q0 < q0low) { |
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q1 += q0low - q0; |
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q0 = q0low; |
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} else if (q1 > q1high) { |
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q0 -= q1 - q1high; |
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q1 = q1high; |
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} |
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} |
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// q0 == q1 isn't really a legal situation |
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if (q0 == q1) { |
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// the following is indirect but guarantees q1 != q0 && q1 near q0 |
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q1 = av_clip(q0+1, 1, SCALE_MAX_POS); |
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q0 = av_clip(q1-1, 0, SCALE_MAX_POS - 1); |
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} |
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for (i = 0; i < TRELLIS_STATES; i++) { |
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paths[0][i].cost = 0.0f; |
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paths[0][i].prev = -1; |
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} |
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for (j = 1; j < TRELLIS_STAGES; j++) { |
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for (i = 0; i < TRELLIS_STATES; i++) { |
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paths[j][i].cost = INFINITY; |
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paths[j][i].prev = -2; |
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} |
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} |
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idx = 1; |
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s->abs_pow34(s->scoefs, sce->coeffs, 1024); |
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for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) { |
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start = w*128; |
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for (g = 0; g < sce->ics.num_swb; g++) { |
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const float *coefs = &sce->coeffs[start]; |
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float qmin, qmax; |
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int nz = 0; |
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bandaddr[idx] = w * 16 + g; |
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qmin = INT_MAX; |
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qmax = 0.0f; |
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for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) { |
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FFPsyBand *band = &s->psy.ch[s->cur_channel].psy_bands[(w+w2)*16+g]; |
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if (band->energy <= band->threshold || band->threshold == 0.0f) { |
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sce->zeroes[(w+w2)*16+g] = 1; |
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continue; |
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} |
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sce->zeroes[(w+w2)*16+g] = 0; |
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nz = 1; |
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for (i = 0; i < sce->ics.swb_sizes[g]; i++) { |
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float t = fabsf(coefs[w2*128+i]); |
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if (t > 0.0f) |
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qmin = FFMIN(qmin, t); |
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qmax = FFMAX(qmax, t); |
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} |
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} |
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if (nz) { |
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int minscale, maxscale; |
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float minrd = INFINITY; |
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float maxval; |
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//minimum scalefactor index is when minimum nonzero coefficient after quantizing is not clipped |
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minscale = coef2minsf(qmin); |
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//maximum scalefactor index is when maximum coefficient after quantizing is still not zero |
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maxscale = coef2maxsf(qmax); |
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minscale = av_clip(minscale - q0, 0, TRELLIS_STATES - 1); |
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maxscale = av_clip(maxscale - q0, 0, TRELLIS_STATES); |
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if (minscale == maxscale) { |
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maxscale = av_clip(minscale+1, 1, TRELLIS_STATES); |
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minscale = av_clip(maxscale-1, 0, TRELLIS_STATES - 1); |
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} |
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maxval = find_max_val(sce->ics.group_len[w], sce->ics.swb_sizes[g], s->scoefs+start); |
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for (q = minscale; q < maxscale; q++) { |
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float dist = 0; |
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int cb = find_min_book(maxval, sce->sf_idx[w*16+g]); |
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for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) { |
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FFPsyBand *band = &s->psy.ch[s->cur_channel].psy_bands[(w+w2)*16+g]; |
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dist += quantize_band_cost(s, coefs + w2*128, s->scoefs + start + w2*128, sce->ics.swb_sizes[g], |
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q + q0, cb, lambda / band->threshold, INFINITY, NULL, NULL, 0); |
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} |
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minrd = FFMIN(minrd, dist); |
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|
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for (i = 0; i < q1 - q0; i++) { |
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float cost; |
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cost = paths[idx - 1][i].cost + dist |
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+ ff_aac_scalefactor_bits[q - i + SCALE_DIFF_ZERO]; |
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if (cost < paths[idx][q].cost) { |
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paths[idx][q].cost = cost; |
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paths[idx][q].prev = i; |
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} |
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} |
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} |
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} else { |
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for (q = 0; q < q1 - q0; q++) { |
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paths[idx][q].cost = paths[idx - 1][q].cost + 1; |
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paths[idx][q].prev = q; |
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} |
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} |
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sce->zeroes[w*16+g] = !nz; |
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start += sce->ics.swb_sizes[g]; |
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idx++; |
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} |
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} |
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idx--; |
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mincost = paths[idx][0].cost; |
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minq = 0; |
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for (i = 1; i < TRELLIS_STATES; i++) { |
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if (paths[idx][i].cost < mincost) { |
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mincost = paths[idx][i].cost; |
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minq = i; |
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} |
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} |
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while (idx) { |
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sce->sf_idx[bandaddr[idx]] = minq + q0; |
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minq = FFMAX(paths[idx][minq].prev, 0); |
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idx--; |
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} |
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//set the same quantizers inside window groups |
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for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) |
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for (g = 0; g < sce->ics.num_swb; g++) |
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for (w2 = 1; w2 < sce->ics.group_len[w]; w2++) |
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sce->sf_idx[(w+w2)*16+g] = sce->sf_idx[w*16+g]; |
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} |
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|
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static void search_for_quantizers_fast(AVCodecContext *avctx, AACEncContext *s, |
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SingleChannelElement *sce, |
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const float lambda) |
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{ |
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int start = 0, i, w, w2, g; |
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int destbits = avctx->bit_rate * 1024.0 / avctx->sample_rate / avctx->channels * (lambda / 120.f); |
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float dists[128] = { 0 }, uplims[128] = { 0 }; |
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float maxvals[128]; |
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int fflag, minscaler; |
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int its = 0; |
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int allz = 0; |
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float minthr = INFINITY; |
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|
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// for values above this the decoder might end up in an endless loop |
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// due to always having more bits than what can be encoded. |
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destbits = FFMIN(destbits, 5800); |
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//some heuristic to determine initial quantizers will reduce search time |
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//determine zero bands and upper limits |
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for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) { |
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start = 0; |
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for (g = 0; g < sce->ics.num_swb; g++) { |
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int nz = 0; |
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float uplim = 0.0f, energy = 0.0f; |
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for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) { |
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FFPsyBand *band = &s->psy.ch[s->cur_channel].psy_bands[(w+w2)*16+g]; |
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uplim += band->threshold; |
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energy += band->energy; |
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if (band->energy <= band->threshold || band->threshold == 0.0f) { |
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sce->zeroes[(w+w2)*16+g] = 1; |
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continue; |
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} |
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nz = 1; |
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} |
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uplims[w*16+g] = uplim *512; |
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sce->band_type[w*16+g] = 0; |
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sce->zeroes[w*16+g] = !nz; |
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if (nz) |
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minthr = FFMIN(minthr, uplim); |
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allz |= nz; |
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start += sce->ics.swb_sizes[g]; |
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} |
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} |
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for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) { |
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for (g = 0; g < sce->ics.num_swb; g++) { |
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if (sce->zeroes[w*16+g]) { |
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sce->sf_idx[w*16+g] = SCALE_ONE_POS; |
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continue; |
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} |
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sce->sf_idx[w*16+g] = SCALE_ONE_POS + FFMIN(log2f(uplims[w*16+g]/minthr)*4,59); |
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} |
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} |
|
|
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if (!allz) |
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return; |
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s->abs_pow34(s->scoefs, sce->coeffs, 1024); |
|
ff_quantize_band_cost_cache_init(s); |
|
|
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for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) { |
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start = w*128; |
|
for (g = 0; g < sce->ics.num_swb; g++) { |
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const float *scaled = s->scoefs + start; |
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maxvals[w*16+g] = find_max_val(sce->ics.group_len[w], sce->ics.swb_sizes[g], scaled); |
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start += sce->ics.swb_sizes[g]; |
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} |
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} |
|
|
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//perform two-loop search |
|
//outer loop - improve quality |
|
do { |
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int tbits, qstep; |
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minscaler = sce->sf_idx[0]; |
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//inner loop - quantize spectrum to fit into given number of bits |
|
qstep = its ? 1 : 32; |
|
do { |
|
int prev = -1; |
|
tbits = 0; |
|
for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) { |
|
start = w*128; |
|
for (g = 0; g < sce->ics.num_swb; g++) { |
|
const float *coefs = sce->coeffs + start; |
|
const float *scaled = s->scoefs + start; |
|
int bits = 0; |
|
int cb; |
|
float dist = 0.0f; |
|
|
|
if (sce->zeroes[w*16+g] || sce->sf_idx[w*16+g] >= 218) { |
|
start += sce->ics.swb_sizes[g]; |
|
continue; |
|
} |
|
minscaler = FFMIN(minscaler, sce->sf_idx[w*16+g]); |
|
cb = find_min_book(maxvals[w*16+g], sce->sf_idx[w*16+g]); |
|
for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) { |
|
int b; |
|
dist += quantize_band_cost_cached(s, w + w2, g, |
|
coefs + w2*128, |
|
scaled + w2*128, |
|
sce->ics.swb_sizes[g], |
|
sce->sf_idx[w*16+g], |
|
cb, 1.0f, INFINITY, |
|
&b, NULL, 0); |
|
bits += b; |
|
} |
|
dists[w*16+g] = dist - bits; |
|
if (prev != -1) { |
|
bits += ff_aac_scalefactor_bits[sce->sf_idx[w*16+g] - prev + SCALE_DIFF_ZERO]; |
|
} |
|
tbits += bits; |
|
start += sce->ics.swb_sizes[g]; |
|
prev = sce->sf_idx[w*16+g]; |
|
} |
|
} |
|
if (tbits > destbits) { |
|
for (i = 0; i < 128; i++) |
|
if (sce->sf_idx[i] < 218 - qstep) |
|
sce->sf_idx[i] += qstep; |
|
} else { |
|
for (i = 0; i < 128; i++) |
|
if (sce->sf_idx[i] > 60 - qstep) |
|
sce->sf_idx[i] -= qstep; |
|
} |
|
qstep >>= 1; |
|
if (!qstep && tbits > destbits*1.02 && sce->sf_idx[0] < 217) |
|
qstep = 1; |
|
} while (qstep); |
|
|
|
fflag = 0; |
|
minscaler = av_clip(minscaler, 60, 255 - SCALE_MAX_DIFF); |
|
|
|
for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) { |
|
for (g = 0; g < sce->ics.num_swb; g++) { |
|
int prevsc = sce->sf_idx[w*16+g]; |
|
if (dists[w*16+g] > uplims[w*16+g] && sce->sf_idx[w*16+g] > 60) { |
|
if (find_min_book(maxvals[w*16+g], sce->sf_idx[w*16+g]-1)) |
|
sce->sf_idx[w*16+g]--; |
|
else //Try to make sure there is some energy in every band |
|
sce->sf_idx[w*16+g]-=2; |
|
} |
|
sce->sf_idx[w*16+g] = av_clip(sce->sf_idx[w*16+g], minscaler, minscaler + SCALE_MAX_DIFF); |
|
sce->sf_idx[w*16+g] = FFMIN(sce->sf_idx[w*16+g], 219); |
|
if (sce->sf_idx[w*16+g] != prevsc) |
|
fflag = 1; |
|
sce->band_type[w*16+g] = find_min_book(maxvals[w*16+g], sce->sf_idx[w*16+g]); |
|
} |
|
} |
|
its++; |
|
} while (fflag && its < 10); |
|
} |
|
|
|
static void search_for_pns(AACEncContext *s, AVCodecContext *avctx, SingleChannelElement *sce) |
|
{ |
|
FFPsyBand *band; |
|
int w, g, w2, i; |
|
int wlen = 1024 / sce->ics.num_windows; |
|
int bandwidth, cutoff; |
|
float *PNS = &s->scoefs[0*128], *PNS34 = &s->scoefs[1*128]; |
|
float *NOR34 = &s->scoefs[3*128]; |
|
uint8_t nextband[128]; |
|
const float lambda = s->lambda; |
|
const float freq_mult = avctx->sample_rate*0.5f/wlen; |
|
const float thr_mult = NOISE_LAMBDA_REPLACE*(100.0f/lambda); |
|
const float spread_threshold = FFMIN(0.75f, NOISE_SPREAD_THRESHOLD*FFMAX(0.5f, lambda/100.f)); |
|
const float dist_bias = av_clipf(4.f * 120 / lambda, 0.25f, 4.0f); |
|
const float pns_transient_energy_r = FFMIN(0.7f, lambda / 140.f); |
|
|
|
int refbits = avctx->bit_rate * 1024.0 / avctx->sample_rate |
|
/ ((avctx->flags & AV_CODEC_FLAG_QSCALE) ? 2.0f : avctx->channels) |
|
* (lambda / 120.f); |
|
|
|
/** Keep this in sync with twoloop's cutoff selection */ |
|
float rate_bandwidth_multiplier = 1.5f; |
|
int prev = -1000, prev_sf = -1; |
|
int frame_bit_rate = (avctx->flags & AV_CODEC_FLAG_QSCALE) |
|
? (refbits * rate_bandwidth_multiplier * avctx->sample_rate / 1024) |
|
: (avctx->bit_rate / avctx->channels); |
|
|
|
frame_bit_rate *= 1.15f; |
|
|
|
if (avctx->cutoff > 0) { |
|
bandwidth = avctx->cutoff; |
|
} else { |
|
bandwidth = FFMAX(3000, AAC_CUTOFF_FROM_BITRATE(frame_bit_rate, 1, avctx->sample_rate)); |
|
} |
|
|
|
cutoff = bandwidth * 2 * wlen / avctx->sample_rate; |
|
|
|
memcpy(sce->band_alt, sce->band_type, sizeof(sce->band_type)); |
|
ff_init_nextband_map(sce, nextband); |
|
for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) { |
|
int wstart = w*128; |
|
for (g = 0; g < sce->ics.num_swb; g++) { |
|
int noise_sfi; |
|
float dist1 = 0.0f, dist2 = 0.0f, noise_amp; |
|
float pns_energy = 0.0f, pns_tgt_energy, energy_ratio, dist_thresh; |
|
float sfb_energy = 0.0f, threshold = 0.0f, spread = 2.0f; |
|
float min_energy = -1.0f, max_energy = 0.0f; |
|
const int start = wstart+sce->ics.swb_offset[g]; |
|
const float freq = (start-wstart)*freq_mult; |
|
const float freq_boost = FFMAX(0.88f*freq/NOISE_LOW_LIMIT, 1.0f); |
|
if (freq < NOISE_LOW_LIMIT || (start-wstart) >= cutoff) { |
|
if (!sce->zeroes[w*16+g]) |
|
prev_sf = sce->sf_idx[w*16+g]; |
|
continue; |
|
} |
|
for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) { |
|
band = &s->psy.ch[s->cur_channel].psy_bands[(w+w2)*16+g]; |
|
sfb_energy += band->energy; |
|
spread = FFMIN(spread, band->spread); |
|
threshold += band->threshold; |
|
if (!w2) { |
|
min_energy = max_energy = band->energy; |
|
} else { |
|
min_energy = FFMIN(min_energy, band->energy); |
|
max_energy = FFMAX(max_energy, band->energy); |
|
} |
|
} |
|
|
|
/* Ramps down at ~8000Hz and loosens the dist threshold */ |
|
dist_thresh = av_clipf(2.5f*NOISE_LOW_LIMIT/freq, 0.5f, 2.5f) * dist_bias; |
|
|
|
/* PNS is acceptable when all of these are true: |
|
* 1. high spread energy (noise-like band) |
|
* 2. near-threshold energy (high PE means the random nature of PNS content will be noticed) |
|
* 3. on short window groups, all windows have similar energy (variations in energy would be destroyed by PNS) |
|
* |
|
* At this stage, point 2 is relaxed for zeroed bands near the noise threshold (hole avoidance is more important) |
|
*/ |
|
if ((!sce->zeroes[w*16+g] && !ff_sfdelta_can_remove_band(sce, nextband, prev_sf, w*16+g)) || |
|
((sce->zeroes[w*16+g] || !sce->band_alt[w*16+g]) && sfb_energy < threshold*sqrtf(1.0f/freq_boost)) || spread < spread_threshold || |
|
(!sce->zeroes[w*16+g] && sce->band_alt[w*16+g] && sfb_energy > threshold*thr_mult*freq_boost) || |
|
min_energy < pns_transient_energy_r * max_energy ) { |
|
sce->pns_ener[w*16+g] = sfb_energy; |
|
if (!sce->zeroes[w*16+g]) |
|
prev_sf = sce->sf_idx[w*16+g]; |
|
continue; |
|
} |
|
|
|
pns_tgt_energy = sfb_energy*FFMIN(1.0f, spread*spread); |
|
noise_sfi = av_clip(roundf(log2f(pns_tgt_energy)*2), -100, 155); /* Quantize */ |
|
noise_amp = -ff_aac_pow2sf_tab[noise_sfi + POW_SF2_ZERO]; /* Dequantize */ |
|
if (prev != -1000) { |
|
int noise_sfdiff = noise_sfi - prev + SCALE_DIFF_ZERO; |
|
if (noise_sfdiff < 0 || noise_sfdiff > 2*SCALE_MAX_DIFF) { |
|
if (!sce->zeroes[w*16+g]) |
|
prev_sf = sce->sf_idx[w*16+g]; |
|
continue; |
|
} |
|
} |
|
for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) { |
|
float band_energy, scale, pns_senergy; |
|
const int start_c = (w+w2)*128+sce->ics.swb_offset[g]; |
|
band = &s->psy.ch[s->cur_channel].psy_bands[(w+w2)*16+g]; |
|
for (i = 0; i < sce->ics.swb_sizes[g]; i++) { |
|
s->random_state = lcg_random(s->random_state); |
|
PNS[i] = s->random_state; |
|
} |
|
band_energy = s->fdsp->scalarproduct_float(PNS, PNS, sce->ics.swb_sizes[g]); |
|
scale = noise_amp/sqrtf(band_energy); |
|
s->fdsp->vector_fmul_scalar(PNS, PNS, scale, sce->ics.swb_sizes[g]); |
|
pns_senergy = s->fdsp->scalarproduct_float(PNS, PNS, sce->ics.swb_sizes[g]); |
|
pns_energy += pns_senergy; |
|
s->abs_pow34(NOR34, &sce->coeffs[start_c], sce->ics.swb_sizes[g]); |
|
s->abs_pow34(PNS34, PNS, sce->ics.swb_sizes[g]); |
|
dist1 += quantize_band_cost(s, &sce->coeffs[start_c], |
|
NOR34, |
|
sce->ics.swb_sizes[g], |
|
sce->sf_idx[(w+w2)*16+g], |
|
sce->band_alt[(w+w2)*16+g], |
|
lambda/band->threshold, INFINITY, NULL, NULL, 0); |
|
/* Estimate rd on average as 5 bits for SF, 4 for the CB, plus spread energy * lambda/thr */ |
|
dist2 += band->energy/(band->spread*band->spread)*lambda*dist_thresh/band->threshold; |
|
} |
|
if (g && sce->band_type[w*16+g-1] == NOISE_BT) { |
|
dist2 += 5; |
|
} else { |
|
dist2 += 9; |
|
} |
|
energy_ratio = pns_tgt_energy/pns_energy; /* Compensates for quantization error */ |
|
sce->pns_ener[w*16+g] = energy_ratio*pns_tgt_energy; |
|
if (sce->zeroes[w*16+g] || !sce->band_alt[w*16+g] || (energy_ratio > 0.85f && energy_ratio < 1.25f && dist2 < dist1)) { |
|
sce->band_type[w*16+g] = NOISE_BT; |
|
sce->zeroes[w*16+g] = 0; |
|
prev = noise_sfi; |
|
} else { |
|
if (!sce->zeroes[w*16+g]) |
|
prev_sf = sce->sf_idx[w*16+g]; |
|
} |
|
} |
|
} |
|
} |
|
|
|
static void mark_pns(AACEncContext *s, AVCodecContext *avctx, SingleChannelElement *sce) |
|
{ |
|
FFPsyBand *band; |
|
int w, g, w2; |
|
int wlen = 1024 / sce->ics.num_windows; |
|
int bandwidth, cutoff; |
|
const float lambda = s->lambda; |
|
const float freq_mult = avctx->sample_rate*0.5f/wlen; |
|
const float spread_threshold = FFMIN(0.75f, NOISE_SPREAD_THRESHOLD*FFMAX(0.5f, lambda/100.f)); |
|
const float pns_transient_energy_r = FFMIN(0.7f, lambda / 140.f); |
|
|
|
int refbits = avctx->bit_rate * 1024.0 / avctx->sample_rate |
|
/ ((avctx->flags & AV_CODEC_FLAG_QSCALE) ? 2.0f : avctx->channels) |
|
* (lambda / 120.f); |
|
|
|
/** Keep this in sync with twoloop's cutoff selection */ |
|
float rate_bandwidth_multiplier = 1.5f; |
|
int frame_bit_rate = (avctx->flags & AV_CODEC_FLAG_QSCALE) |
|
? (refbits * rate_bandwidth_multiplier * avctx->sample_rate / 1024) |
|
: (avctx->bit_rate / avctx->channels); |
|
|
|
frame_bit_rate *= 1.15f; |
|
|
|
if (avctx->cutoff > 0) { |
|
bandwidth = avctx->cutoff; |
|
} else { |
|
bandwidth = FFMAX(3000, AAC_CUTOFF_FROM_BITRATE(frame_bit_rate, 1, avctx->sample_rate)); |
|
} |
|
|
|
cutoff = bandwidth * 2 * wlen / avctx->sample_rate; |
|
|
|
memcpy(sce->band_alt, sce->band_type, sizeof(sce->band_type)); |
|
for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) { |
|
for (g = 0; g < sce->ics.num_swb; g++) { |
|
float sfb_energy = 0.0f, threshold = 0.0f, spread = 2.0f; |
|
float min_energy = -1.0f, max_energy = 0.0f; |
|
const int start = sce->ics.swb_offset[g]; |
|
const float freq = start*freq_mult; |
|
const float freq_boost = FFMAX(0.88f*freq/NOISE_LOW_LIMIT, 1.0f); |
|
if (freq < NOISE_LOW_LIMIT || start >= cutoff) { |
|
sce->can_pns[w*16+g] = 0; |
|
continue; |
|
} |
|
for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) { |
|
band = &s->psy.ch[s->cur_channel].psy_bands[(w+w2)*16+g]; |
|
sfb_energy += band->energy; |
|
spread = FFMIN(spread, band->spread); |
|
threshold += band->threshold; |
|
if (!w2) { |
|
min_energy = max_energy = band->energy; |
|
} else { |
|
min_energy = FFMIN(min_energy, band->energy); |
|
max_energy = FFMAX(max_energy, band->energy); |
|
} |
|
} |
|
|
|
/* PNS is acceptable when all of these are true: |
|
* 1. high spread energy (noise-like band) |
|
* 2. near-threshold energy (high PE means the random nature of PNS content will be noticed) |
|
* 3. on short window groups, all windows have similar energy (variations in energy would be destroyed by PNS) |
|
*/ |
|
sce->pns_ener[w*16+g] = sfb_energy; |
|
if (sfb_energy < threshold*sqrtf(1.5f/freq_boost) || spread < spread_threshold || min_energy < pns_transient_energy_r * max_energy) { |
|
sce->can_pns[w*16+g] = 0; |
|
} else { |
|
sce->can_pns[w*16+g] = 1; |
|
} |
|
} |
|
} |
|
} |
|
|
|
static void search_for_ms(AACEncContext *s, ChannelElement *cpe) |
|
{ |
|
int start = 0, i, w, w2, g, sid_sf_boost, prev_mid, prev_side; |
|
uint8_t nextband0[128], nextband1[128]; |
|
float *M = s->scoefs + 128*0, *S = s->scoefs + 128*1; |
|
float *L34 = s->scoefs + 128*2, *R34 = s->scoefs + 128*3; |
|
float *M34 = s->scoefs + 128*4, *S34 = s->scoefs + 128*5; |
|
const float lambda = s->lambda; |
|
const float mslambda = FFMIN(1.0f, lambda / 120.f); |
|
SingleChannelElement *sce0 = &cpe->ch[0]; |
|
SingleChannelElement *sce1 = &cpe->ch[1]; |
|
if (!cpe->common_window) |
|
return; |
|
|
|
/** Scout out next nonzero bands */ |
|
ff_init_nextband_map(sce0, nextband0); |
|
ff_init_nextband_map(sce1, nextband1); |
|
|
|
prev_mid = sce0->sf_idx[0]; |
|
prev_side = sce1->sf_idx[0]; |
|
for (w = 0; w < sce0->ics.num_windows; w += sce0->ics.group_len[w]) { |
|
start = 0; |
|
for (g = 0; g < sce0->ics.num_swb; g++) { |
|
float bmax = bval2bmax(g * 17.0f / sce0->ics.num_swb) / 0.0045f; |
|
if (!cpe->is_mask[w*16+g]) |
|
cpe->ms_mask[w*16+g] = 0; |
|
if (!sce0->zeroes[w*16+g] && !sce1->zeroes[w*16+g] && !cpe->is_mask[w*16+g]) { |
|
float Mmax = 0.0f, Smax = 0.0f; |
|
|
|
/* Must compute mid/side SF and book for the whole window group */ |
|
for (w2 = 0; w2 < sce0->ics.group_len[w]; w2++) { |
|
for (i = 0; i < sce0->ics.swb_sizes[g]; i++) { |
|
M[i] = (sce0->coeffs[start+(w+w2)*128+i] |
|
+ sce1->coeffs[start+(w+w2)*128+i]) * 0.5; |
|
S[i] = M[i] |
|
- sce1->coeffs[start+(w+w2)*128+i]; |
|
} |
|
s->abs_pow34(M34, M, sce0->ics.swb_sizes[g]); |
|
s->abs_pow34(S34, S, sce0->ics.swb_sizes[g]); |
|
for (i = 0; i < sce0->ics.swb_sizes[g]; i++ ) { |
|
Mmax = FFMAX(Mmax, M34[i]); |
|
Smax = FFMAX(Smax, S34[i]); |
|
} |
|
} |
|
|
|
for (sid_sf_boost = 0; sid_sf_boost < 4; sid_sf_boost++) { |
|
float dist1 = 0.0f, dist2 = 0.0f; |
|
int B0 = 0, B1 = 0; |
|
int minidx; |
|
int mididx, sididx; |
|
int midcb, sidcb; |
|
|
|
minidx = FFMIN(sce0->sf_idx[w*16+g], sce1->sf_idx[w*16+g]); |
|
mididx = av_clip(minidx, 0, SCALE_MAX_POS - SCALE_DIV_512); |
|
sididx = av_clip(minidx - sid_sf_boost * 3, 0, SCALE_MAX_POS - SCALE_DIV_512); |
|
if (sce0->band_type[w*16+g] != NOISE_BT && sce1->band_type[w*16+g] != NOISE_BT |
|
&& ( !ff_sfdelta_can_replace(sce0, nextband0, prev_mid, mididx, w*16+g) |
|
|| !ff_sfdelta_can_replace(sce1, nextband1, prev_side, sididx, w*16+g))) { |
|
/* scalefactor range violation, bad stuff, will decrease quality unacceptably */ |
|
continue; |
|
} |
|
|
|
midcb = find_min_book(Mmax, mididx); |
|
sidcb = find_min_book(Smax, sididx); |
|
|
|
/* No CB can be zero */ |
|
midcb = FFMAX(1,midcb); |
|
sidcb = FFMAX(1,sidcb); |
|
|
|
for (w2 = 0; w2 < sce0->ics.group_len[w]; w2++) { |
|
FFPsyBand *band0 = &s->psy.ch[s->cur_channel+0].psy_bands[(w+w2)*16+g]; |
|
FFPsyBand *band1 = &s->psy.ch[s->cur_channel+1].psy_bands[(w+w2)*16+g]; |
|
float minthr = FFMIN(band0->threshold, band1->threshold); |
|
int b1,b2,b3,b4; |
|
for (i = 0; i < sce0->ics.swb_sizes[g]; i++) { |
|
M[i] = (sce0->coeffs[start+(w+w2)*128+i] |
|
+ sce1->coeffs[start+(w+w2)*128+i]) * 0.5; |
|
S[i] = M[i] |
|
- sce1->coeffs[start+(w+w2)*128+i]; |
|
} |
|
|
|
s->abs_pow34(L34, sce0->coeffs+start+(w+w2)*128, sce0->ics.swb_sizes[g]); |
|
s->abs_pow34(R34, sce1->coeffs+start+(w+w2)*128, sce0->ics.swb_sizes[g]); |
|
s->abs_pow34(M34, M, sce0->ics.swb_sizes[g]); |
|
s->abs_pow34(S34, S, sce0->ics.swb_sizes[g]); |
|
dist1 += quantize_band_cost(s, &sce0->coeffs[start + (w+w2)*128], |
|
L34, |
|
sce0->ics.swb_sizes[g], |
|
sce0->sf_idx[w*16+g], |
|
sce0->band_type[w*16+g], |
|
lambda / (band0->threshold + FLT_MIN), INFINITY, &b1, NULL, 0); |
|
dist1 += quantize_band_cost(s, &sce1->coeffs[start + (w+w2)*128], |
|
R34, |
|
sce1->ics.swb_sizes[g], |
|
sce1->sf_idx[w*16+g], |
|
sce1->band_type[w*16+g], |
|
lambda / (band1->threshold + FLT_MIN), INFINITY, &b2, NULL, 0); |
|
dist2 += quantize_band_cost(s, M, |
|
M34, |
|
sce0->ics.swb_sizes[g], |
|
mididx, |
|
midcb, |
|
lambda / (minthr + FLT_MIN), INFINITY, &b3, NULL, 0); |
|
dist2 += quantize_band_cost(s, S, |
|
S34, |
|
sce1->ics.swb_sizes[g], |
|
sididx, |
|
sidcb, |
|
mslambda / (minthr * bmax + FLT_MIN), INFINITY, &b4, NULL, 0); |
|
B0 += b1+b2; |
|
B1 += b3+b4; |
|
dist1 -= b1+b2; |
|
dist2 -= b3+b4; |
|
} |
|
cpe->ms_mask[w*16+g] = dist2 <= dist1 && B1 < B0; |
|
if (cpe->ms_mask[w*16+g]) { |
|
if (sce0->band_type[w*16+g] != NOISE_BT && sce1->band_type[w*16+g] != NOISE_BT) { |
|
sce0->sf_idx[w*16+g] = mididx; |
|
sce1->sf_idx[w*16+g] = sididx; |
|
sce0->band_type[w*16+g] = midcb; |
|
sce1->band_type[w*16+g] = sidcb; |
|
} else if ((sce0->band_type[w*16+g] != NOISE_BT) ^ (sce1->band_type[w*16+g] != NOISE_BT)) { |
|
/* ms_mask unneeded, and it confuses some decoders */ |
|
cpe->ms_mask[w*16+g] = 0; |
|
} |
|
break; |
|
} else if (B1 > B0) { |
|
/* More boost won't fix this */ |
|
break; |
|
} |
|
} |
|
} |
|
if (!sce0->zeroes[w*16+g] && sce0->band_type[w*16+g] < RESERVED_BT) |
|
prev_mid = sce0->sf_idx[w*16+g]; |
|
if (!sce1->zeroes[w*16+g] && !cpe->is_mask[w*16+g] && sce1->band_type[w*16+g] < RESERVED_BT) |
|
prev_side = sce1->sf_idx[w*16+g]; |
|
start += sce0->ics.swb_sizes[g]; |
|
} |
|
} |
|
} |
|
|
|
const AACCoefficientsEncoder ff_aac_coders[AAC_CODER_NB] = { |
|
[AAC_CODER_ANMR] = { |
|
search_for_quantizers_anmr, |
|
encode_window_bands_info, |
|
quantize_and_encode_band, |
|
ff_aac_encode_tns_info, |
|
ff_aac_encode_ltp_info, |
|
ff_aac_encode_main_pred, |
|
ff_aac_adjust_common_pred, |
|
ff_aac_adjust_common_ltp, |
|
ff_aac_apply_main_pred, |
|
ff_aac_apply_tns, |
|
ff_aac_update_ltp, |
|
ff_aac_ltp_insert_new_frame, |
|
set_special_band_scalefactors, |
|
search_for_pns, |
|
mark_pns, |
|
ff_aac_search_for_tns, |
|
ff_aac_search_for_ltp, |
|
search_for_ms, |
|
ff_aac_search_for_is, |
|
ff_aac_search_for_pred, |
|
}, |
|
[AAC_CODER_TWOLOOP] = { |
|
search_for_quantizers_twoloop, |
|
codebook_trellis_rate, |
|
quantize_and_encode_band, |
|
ff_aac_encode_tns_info, |
|
ff_aac_encode_ltp_info, |
|
ff_aac_encode_main_pred, |
|
ff_aac_adjust_common_pred, |
|
ff_aac_adjust_common_ltp, |
|
ff_aac_apply_main_pred, |
|
ff_aac_apply_tns, |
|
ff_aac_update_ltp, |
|
ff_aac_ltp_insert_new_frame, |
|
set_special_band_scalefactors, |
|
search_for_pns, |
|
mark_pns, |
|
ff_aac_search_for_tns, |
|
ff_aac_search_for_ltp, |
|
search_for_ms, |
|
ff_aac_search_for_is, |
|
ff_aac_search_for_pred, |
|
}, |
|
[AAC_CODER_FAST] = { |
|
search_for_quantizers_fast, |
|
codebook_trellis_rate, |
|
quantize_and_encode_band, |
|
ff_aac_encode_tns_info, |
|
ff_aac_encode_ltp_info, |
|
ff_aac_encode_main_pred, |
|
ff_aac_adjust_common_pred, |
|
ff_aac_adjust_common_ltp, |
|
ff_aac_apply_main_pred, |
|
ff_aac_apply_tns, |
|
ff_aac_update_ltp, |
|
ff_aac_ltp_insert_new_frame, |
|
set_special_band_scalefactors, |
|
search_for_pns, |
|
mark_pns, |
|
ff_aac_search_for_tns, |
|
ff_aac_search_for_ltp, |
|
search_for_ms, |
|
ff_aac_search_for_is, |
|
ff_aac_search_for_pred, |
|
}, |
|
};
|
|
|