| /* |
| * AAC encoder twoloop coder |
| * Copyright (C) 2008-2009 Konstantin Shishkov |
| * |
| * 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 encoder twoloop coder |
| * @author Konstantin Shishkov, Claudio Freire |
| */ |
| |
| /** |
| * This file contains a template for the twoloop coder function. |
| * It needs to be provided, externally, as an already included declaration, |
| * the following functions from aacenc_quantization/util.h. They're not included |
| * explicitly here to make it possible to provide alternative implementations: |
| * - quantize_band_cost |
| * - abs_pow34_v |
| * - find_max_val |
| * - find_min_book |
| * - find_form_factor |
| */ |
| |
| #ifndef AVCODEC_AACCODER_TWOLOOP_H |
| #define AVCODEC_AACCODER_TWOLOOP_H |
| |
| #include <float.h> |
| #include "libavutil/mathematics.h" |
| #include "mathops.h" |
| #include "avcodec.h" |
| #include "put_bits.h" |
| #include "aac.h" |
| #include "aacenc.h" |
| #include "aactab.h" |
| #include "aacenctab.h" |
| |
| /** Frequency in Hz for lower limit of noise substitution **/ |
| #define NOISE_LOW_LIMIT 4000 |
| |
| #define sclip(x) av_clip(x,60,218) |
| |
| /* Reflects the cost to change codebooks */ |
| static inline int ff_pns_bits(SingleChannelElement *sce, int w, int g) |
| { |
| return (!g || !sce->zeroes[w*16+g-1] || !sce->can_pns[w*16+g-1]) ? 9 : 5; |
| } |
| |
| /** |
| * two-loop quantizers search taken from ISO 13818-7 Appendix C |
| */ |
| static void search_for_quantizers_twoloop(AVCodecContext *avctx, |
| AACEncContext *s, |
| SingleChannelElement *sce, |
| const float lambda) |
| { |
| int start = 0, i, w, w2, g, recomprd; |
| int destbits = avctx->bit_rate * 1024.0 / avctx->sample_rate |
| / ((avctx->flags & CODEC_FLAG_QSCALE) ? 2.0f : avctx->channels) |
| * (lambda / 120.f); |
| int refbits = destbits; |
| int toomanybits, toofewbits; |
| char nzs[128]; |
| uint8_t nextband[128]; |
| int maxsf[128]; |
| float dists[128] = { 0 }, qenergies[128] = { 0 }, uplims[128], euplims[128], energies[128]; |
| float maxvals[128], spread_thr_r[128]; |
| float min_spread_thr_r, max_spread_thr_r; |
| |
| /** |
| * rdlambda controls the maximum tolerated distortion. Twoloop |
| * will keep iterating until it fails to lower it or it reaches |
| * ulimit * rdlambda. Keeping it low increases quality on difficult |
| * signals, but lower it too much, and bits will be taken from weak |
| * signals, creating "holes". A balance is necesary. |
| * rdmax and rdmin specify the relative deviation from rdlambda |
| * allowed for tonality compensation |
| */ |
| float rdlambda = av_clipf(2.0f * 120.f / lambda, 0.0625f, 16.0f); |
| const float nzslope = 1.5f; |
| float rdmin = 0.03125f; |
| float rdmax = 1.0f; |
| |
| /** |
| * sfoffs controls an offset of optmium allocation that will be |
| * applied based on lambda. Keep it real and modest, the loop |
| * will take care of the rest, this just accelerates convergence |
| */ |
| float sfoffs = av_clipf(log2f(120.0f / lambda) * 4.0f, -5, 10); |
| |
| int fflag, minscaler, maxscaler, nminscaler; |
| int its = 0; |
| int maxits = 30; |
| int allz = 0; |
| int tbits; |
| int cutoff = 1024; |
| int pns_start_pos; |
| int prev; |
| |
| /** |
| * zeroscale controls a multiplier of the threshold, if band energy |
| * is below this, a zero is forced. Keep it lower than 1, unless |
| * low lambda is used, because energy < threshold doesn't mean there's |
| * no audible signal outright, it's just energy. Also make it rise |
| * slower than rdlambda, as rdscale has due compensation with |
| * noisy band depriorization below, whereas zeroing logic is rather dumb |
| */ |
| float zeroscale; |
| if (lambda > 120.f) { |
| zeroscale = av_clipf(powf(120.f / lambda, 0.25f), 0.0625f, 1.0f); |
| } else { |
| zeroscale = 1.f; |
| } |
| |
| if (s->psy.bitres.alloc >= 0) { |
| /** |
| * Psy granted us extra bits to use, from the reservoire |
| * adjust for lambda except what psy already did |
| */ |
| destbits = s->psy.bitres.alloc |
| * (lambda / (avctx->global_quality ? avctx->global_quality : 120)); |
| } |
| |
| if (avctx->flags & CODEC_FLAG_QSCALE) { |
| /** |
| * Constant Q-scale doesn't compensate MS coding on its own |
| * No need to be overly precise, this only controls RD |
| * adjustment CB limits when going overboard |
| */ |
| if (s->options.mid_side && s->cur_type == TYPE_CPE) |
| destbits *= 2; |
| |
| /** |
| * When using a constant Q-scale, don't adjust bits, just use RD |
| * Don't let it go overboard, though... 8x psy target is enough |
| */ |
| toomanybits = 5800; |
| toofewbits = destbits / 16; |
| |
| /** Don't offset scalers, just RD */ |
| sfoffs = sce->ics.num_windows - 1; |
| rdlambda = sqrtf(rdlambda); |
| |
| /** search further */ |
| maxits *= 2; |
| } else { |
| /* When using ABR, be strict, but a reasonable leeway is |
| * critical to allow RC to smoothly track desired bitrate |
| * without sudden quality drops that cause audible artifacts. |
| * Symmetry is also desirable, to avoid systematic bias. |
| */ |
| toomanybits = destbits + destbits/8; |
| toofewbits = destbits - destbits/8; |
| |
| sfoffs = 0; |
| rdlambda = sqrtf(rdlambda); |
| } |
| |
| /** and zero out above cutoff frequency */ |
| { |
| int wlen = 1024 / sce->ics.num_windows; |
| int bandwidth; |
| |
| /** |
| * Scale, psy gives us constant quality, this LP only scales |
| * bitrate by lambda, so we save bits on subjectively unimportant HF |
| * rather than increase quantization noise. Adjust nominal bitrate |
| * to effective bitrate according to encoding parameters, |
| * AAC_CUTOFF_FROM_BITRATE is calibrated for effective bitrate. |
| */ |
| float rate_bandwidth_multiplier = 1.5f; |
| int frame_bit_rate = (avctx->flags & CODEC_FLAG_QSCALE) |
| ? (refbits * rate_bandwidth_multiplier * avctx->sample_rate / 1024) |
| : (avctx->bit_rate / avctx->channels); |
| |
| /** Compensate for extensions that increase efficiency */ |
| if (s->options.pns || s->options.intensity_stereo) |
| 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)); |
| s->psy.cutoff = bandwidth; |
| } |
| |
| cutoff = bandwidth * 2 * wlen / avctx->sample_rate; |
| pns_start_pos = NOISE_LOW_LIMIT * 2 * wlen / avctx->sample_rate; |
| } |
| |
| /** |
| * for values above this the decoder might end up in an endless loop |
| * due to always having more bits than what can be encoded. |
| */ |
| destbits = FFMIN(destbits, 5800); |
| toomanybits = FFMIN(toomanybits, 5800); |
| toofewbits = FFMIN(toofewbits, 5800); |
| /** |
| * XXX: some heuristic to determine initial quantizers will reduce search time |
| * determine zero bands and upper distortion limits |
| */ |
| min_spread_thr_r = -1; |
| max_spread_thr_r = -1; |
| for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) { |
| for (g = start = 0; g < sce->ics.num_swb; start += sce->ics.swb_sizes[g++]) { |
| int nz = 0; |
| float uplim = 0.0f, energy = 0.0f, spread = 0.0f; |
| for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) { |
| FFPsyBand *band = &s->psy.ch[s->cur_channel].psy_bands[(w+w2)*16+g]; |
| if (start >= cutoff || band->energy <= (band->threshold * zeroscale) || band->threshold == 0.0f) { |
| sce->zeroes[(w+w2)*16+g] = 1; |
| continue; |
| } |
| nz = 1; |
| } |
| if (!nz) { |
| uplim = 0.0f; |
| } else { |
| nz = 0; |
| for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) { |
| FFPsyBand *band = &s->psy.ch[s->cur_channel].psy_bands[(w+w2)*16+g]; |
| if (band->energy <= (band->threshold * zeroscale) || band->threshold == 0.0f) |
| continue; |
| uplim += band->threshold; |
| energy += band->energy; |
| spread += band->spread; |
| nz++; |
| } |
| } |
| uplims[w*16+g] = uplim; |
| energies[w*16+g] = energy; |
| nzs[w*16+g] = nz; |
| sce->zeroes[w*16+g] = !nz; |
| allz |= nz; |
| if (nz && sce->can_pns[w*16+g]) { |
| spread_thr_r[w*16+g] = energy * nz / (uplim * spread); |
| if (min_spread_thr_r < 0) { |
| min_spread_thr_r = max_spread_thr_r = spread_thr_r[w*16+g]; |
| } else { |
| min_spread_thr_r = FFMIN(min_spread_thr_r, spread_thr_r[w*16+g]); |
| max_spread_thr_r = FFMAX(max_spread_thr_r, spread_thr_r[w*16+g]); |
| } |
| } |
| } |
| } |
| |
| /** Compute initial scalers */ |
| minscaler = 65535; |
| for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) { |
| for (g = 0; g < sce->ics.num_swb; g++) { |
| if (sce->zeroes[w*16+g]) { |
| sce->sf_idx[w*16+g] = SCALE_ONE_POS; |
| continue; |
| } |
| /** |
| * log2f-to-distortion ratio is, technically, 2 (1.5db = 4, but it's power vs level so it's 2). |
| * But, as offsets are applied, low-frequency signals are too sensitive to the induced distortion, |
| * so we make scaling more conservative by choosing a lower log2f-to-distortion ratio, and thus |
| * more robust. |
| */ |
| sce->sf_idx[w*16+g] = av_clip( |
| SCALE_ONE_POS |
| + 1.75*log2f(FFMAX(0.00125f,uplims[w*16+g]) / sce->ics.swb_sizes[g]) |
| + sfoffs, |
| 60, SCALE_MAX_POS); |
| minscaler = FFMIN(minscaler, sce->sf_idx[w*16+g]); |
| } |
| } |
| |
| /** Clip */ |
| minscaler = av_clip(minscaler, SCALE_ONE_POS - SCALE_DIV_512, SCALE_MAX_POS - SCALE_DIV_512); |
| for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) |
| for (g = 0; g < sce->ics.num_swb; g++) |
| if (!sce->zeroes[w*16+g]) |
| sce->sf_idx[w*16+g] = av_clip(sce->sf_idx[w*16+g], minscaler, minscaler + SCALE_MAX_DIFF - 1); |
| |
| if (!allz) |
| return; |
| abs_pow34_v(s->scoefs, sce->coeffs, 1024); |
| ff_quantize_band_cost_cache_init(s); |
| |
| 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 *scaled = s->scoefs + start; |
| maxvals[w*16+g] = find_max_val(sce->ics.group_len[w], sce->ics.swb_sizes[g], scaled); |
| start += sce->ics.swb_sizes[g]; |
| } |
| } |
| |
| /** |
| * Scale uplims to match rate distortion to quality |
| * bu applying noisy band depriorization and tonal band priorization. |
| * Maxval-energy ratio gives us an idea of how noisy/tonal the band is. |
| * If maxval^2 ~ energy, then that band is mostly noise, and we can relax |
| * rate distortion requirements. |
| */ |
| memcpy(euplims, uplims, sizeof(euplims)); |
| for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) { |
| /** psy already priorizes transients to some extent */ |
| float de_psy_factor = (sce->ics.num_windows > 1) ? 8.0f / sce->ics.group_len[w] : 1.0f; |
| start = w*128; |
| for (g = 0; g < sce->ics.num_swb; g++) { |
| if (nzs[g] > 0) { |
| float cleanup_factor = ff_sqrf(av_clipf(start / (cutoff * 0.75f), 1.0f, 2.0f)); |
| float energy2uplim = find_form_factor( |
| sce->ics.group_len[w], sce->ics.swb_sizes[g], |
| uplims[w*16+g] / (nzs[g] * sce->ics.swb_sizes[w]), |
| sce->coeffs + start, |
| nzslope * cleanup_factor); |
| energy2uplim *= de_psy_factor; |
| if (!(avctx->flags & CODEC_FLAG_QSCALE)) { |
| /** In ABR, we need to priorize less and let rate control do its thing */ |
| energy2uplim = sqrtf(energy2uplim); |
| } |
| energy2uplim = FFMAX(0.015625f, FFMIN(1.0f, energy2uplim)); |
| uplims[w*16+g] *= av_clipf(rdlambda * energy2uplim, rdmin, rdmax) |
| * sce->ics.group_len[w]; |
| |
| energy2uplim = find_form_factor( |
| sce->ics.group_len[w], sce->ics.swb_sizes[g], |
| uplims[w*16+g] / (nzs[g] * sce->ics.swb_sizes[w]), |
| sce->coeffs + start, |
| 2.0f); |
| energy2uplim *= de_psy_factor; |
| if (!(avctx->flags & CODEC_FLAG_QSCALE)) { |
| /** In ABR, we need to priorize less and let rate control do its thing */ |
| energy2uplim = sqrtf(energy2uplim); |
| } |
| energy2uplim = FFMAX(0.015625f, FFMIN(1.0f, energy2uplim)); |
| euplims[w*16+g] *= av_clipf(rdlambda * energy2uplim * sce->ics.group_len[w], |
| 0.5f, 1.0f); |
| } |
| start += sce->ics.swb_sizes[g]; |
| } |
| } |
| |
| for (i = 0; i < sizeof(maxsf) / sizeof(maxsf[0]); ++i) |
| maxsf[i] = SCALE_MAX_POS; |
| |
| //perform two-loop search |
| //outer loop - improve quality |
| do { |
| //inner loop - quantize spectrum to fit into given number of bits |
| int overdist; |
| int qstep = its ? 1 : 32; |
| do { |
| int changed = 0; |
| prev = -1; |
| recomprd = 0; |
| 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; |
| float qenergy = 0.0f; |
| |
| if (sce->zeroes[w*16+g] || sce->sf_idx[w*16+g] >= 218) { |
| start += sce->ics.swb_sizes[g]; |
| if (sce->can_pns[w*16+g]) { |
| /** PNS isn't free */ |
| tbits += ff_pns_bits(sce, w, g); |
| } |
| continue; |
| } |
| 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; |
| float sqenergy; |
| 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, &sqenergy, |
| 0); |
| bits += b; |
| qenergy += sqenergy; |
| } |
| dists[w*16+g] = dist - bits; |
| qenergies[w*16+g] = qenergy; |
| if (prev != -1) { |
| int sfdiff = av_clip(sce->sf_idx[w*16+g] - prev + SCALE_DIFF_ZERO, 0, 2*SCALE_MAX_DIFF); |
| bits += ff_aac_scalefactor_bits[sfdiff]; |
| } |
| tbits += bits; |
| start += sce->ics.swb_sizes[g]; |
| prev = sce->sf_idx[w*16+g]; |
| } |
| } |
| if (tbits > toomanybits) { |
| recomprd = 1; |
| for (i = 0; i < 128; i++) { |
| if (sce->sf_idx[i] < (SCALE_MAX_POS - SCALE_DIV_512)) { |
| int maxsf_i = (tbits > 5800) ? SCALE_MAX_POS : maxsf[i]; |
| int new_sf = FFMIN(maxsf_i, sce->sf_idx[i] + qstep); |
| if (new_sf != sce->sf_idx[i]) { |
| sce->sf_idx[i] = new_sf; |
| changed = 1; |
| } |
| } |
| } |
| } else if (tbits < toofewbits) { |
| recomprd = 1; |
| for (i = 0; i < 128; i++) { |
| if (sce->sf_idx[i] > SCALE_ONE_POS) { |
| int new_sf = FFMAX(SCALE_ONE_POS, sce->sf_idx[i] - qstep); |
| if (new_sf != sce->sf_idx[i]) { |
| sce->sf_idx[i] = new_sf; |
| changed = 1; |
| } |
| } |
| } |
| } |
| qstep >>= 1; |
| if (!qstep && tbits > toomanybits && sce->sf_idx[0] < 217 && changed) |
| qstep = 1; |
| } while (qstep); |
| |
| overdist = 1; |
| fflag = tbits < toofewbits; |
| for (i = 0; i < 2 && (overdist || recomprd); ++i) { |
| if (recomprd) { |
| /** Must recompute distortion */ |
| 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; |
| float qenergy = 0.0f; |
| |
| if (sce->zeroes[w*16+g] || sce->sf_idx[w*16+g] >= 218) { |
| start += sce->ics.swb_sizes[g]; |
| if (sce->can_pns[w*16+g]) { |
| /** PNS isn't free */ |
| tbits += ff_pns_bits(sce, w, g); |
| } |
| continue; |
| } |
| 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; |
| float sqenergy; |
| 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, &sqenergy, |
| 0); |
| bits += b; |
| qenergy += sqenergy; |
| } |
| dists[w*16+g] = dist - bits; |
| qenergies[w*16+g] = qenergy; |
| if (prev != -1) { |
| int sfdiff = av_clip(sce->sf_idx[w*16+g] - prev + SCALE_DIFF_ZERO, 0, 2*SCALE_MAX_DIFF); |
| bits += ff_aac_scalefactor_bits[sfdiff]; |
| } |
| tbits += bits; |
| start += sce->ics.swb_sizes[g]; |
| prev = sce->sf_idx[w*16+g]; |
| } |
| } |
| } |
| if (!i && s->options.pns && its > maxits/2 && tbits > toofewbits) { |
| float maxoverdist = 0.0f; |
| float ovrfactor = 1.f+(maxits-its)*16.f/maxits; |
| overdist = recomprd = 0; |
| for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) { |
| for (g = start = 0; g < sce->ics.num_swb; start += sce->ics.swb_sizes[g++]) { |
| if (!sce->zeroes[w*16+g] && sce->sf_idx[w*16+g] > SCALE_ONE_POS && dists[w*16+g] > uplims[w*16+g]*ovrfactor) { |
| float ovrdist = dists[w*16+g] / FFMAX(uplims[w*16+g],euplims[w*16+g]); |
| maxoverdist = FFMAX(maxoverdist, ovrdist); |
| overdist++; |
| } |
| } |
| } |
| if (overdist) { |
| /* We have overdistorted bands, trade for zeroes (that can be noise) |
| * Zero the bands in the lowest 1.25% spread-energy-threshold ranking |
| */ |
| float minspread = max_spread_thr_r; |
| float maxspread = min_spread_thr_r; |
| float zspread; |
| int zeroable = 0; |
| int zeroed = 0; |
| int maxzeroed, zloop; |
| for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) { |
| for (g = start = 0; g < sce->ics.num_swb; start += sce->ics.swb_sizes[g++]) { |
| if (start >= pns_start_pos && !sce->zeroes[w*16+g] && sce->can_pns[w*16+g]) { |
| minspread = FFMIN(minspread, spread_thr_r[w*16+g]); |
| maxspread = FFMAX(maxspread, spread_thr_r[w*16+g]); |
| zeroable++; |
| } |
| } |
| } |
| zspread = (maxspread-minspread) * 0.0125f + minspread; |
| /* Don't PNS everything even if allowed. It suppresses bit starvation signals from RC, |
| * and forced the hand of the later search_for_pns step. |
| * Instead, PNS a fraction of the spread_thr_r range depending on how starved for bits we are, |
| * and leave further PNSing to search_for_pns if worthwhile. |
| */ |
| zspread = FFMIN3(min_spread_thr_r * 8.f, zspread, |
| ((toomanybits - tbits) * min_spread_thr_r + (tbits - toofewbits) * max_spread_thr_r) / (toomanybits - toofewbits + 1)); |
| maxzeroed = FFMIN(zeroable, FFMAX(1, (zeroable * its + maxits - 1) / (2 * maxits))); |
| for (zloop = 0; zloop < 2; zloop++) { |
| /* Two passes: first distorted stuff - two birds in one shot and all that, |
| * then anything viable. Viable means not zero, but either CB=zero-able |
| * (too high SF), not SF <= 1 (that means we'd be operating at very high |
| * quality, we don't want PNS when doing VHQ), PNS allowed, and within |
| * the lowest ranking percentile. |
| */ |
| float loopovrfactor = (zloop) ? 1.0f : ovrfactor; |
| int loopminsf = (zloop) ? (SCALE_ONE_POS - SCALE_DIV_512) : SCALE_ONE_POS; |
| int mcb; |
| for (g = sce->ics.num_swb-1; g > 0 && zeroed < maxzeroed; g--) { |
| if (sce->ics.swb_offset[g] < pns_start_pos) |
| continue; |
| for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) { |
| if (!sce->zeroes[w*16+g] && sce->can_pns[w*16+g] && spread_thr_r[w*16+g] <= zspread |
| && sce->sf_idx[w*16+g] > loopminsf |
| && (dists[w*16+g] > loopovrfactor*uplims[w*16+g] || !(mcb = find_min_book(maxvals[w*16+g], sce->sf_idx[w*16+g])) |
| || (mcb <= 1 && dists[w*16+g] > FFMIN(uplims[w*16+g], euplims[w*16+g]))) ) { |
| sce->zeroes[w*16+g] = 1; |
| sce->band_type[w*16+g] = 0; |
| zeroed++; |
| } |
| } |
| } |
| } |
| if (zeroed) |
| recomprd = fflag = 1; |
| } else { |
| overdist = 0; |
| } |
| } |
| } |
| |
| minscaler = SCALE_MAX_POS; |
| maxscaler = 0; |
| for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) { |
| for (g = 0; g < sce->ics.num_swb; g++) { |
| if (!sce->zeroes[w*16+g]) { |
| minscaler = FFMIN(minscaler, sce->sf_idx[w*16+g]); |
| maxscaler = FFMAX(maxscaler, sce->sf_idx[w*16+g]); |
| } |
| } |
| } |
| |
| minscaler = nminscaler = av_clip(minscaler, SCALE_ONE_POS - SCALE_DIV_512, SCALE_MAX_POS - SCALE_DIV_512); |
| prev = -1; |
| for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) { |
| /** Start with big steps, end up fine-tunning */ |
| int depth = (its > maxits/2) ? ((its > maxits*2/3) ? 1 : 3) : 10; |
| int edepth = depth+2; |
| float uplmax = its / (maxits*0.25f) + 1.0f; |
| uplmax *= (tbits > destbits) ? FFMIN(2.0f, tbits / (float)FFMAX(1,destbits)) : 1.0f; |
| start = w * 128; |
| for (g = 0; g < sce->ics.num_swb; g++) { |
| int prevsc = sce->sf_idx[w*16+g]; |
| if (prev < 0 && !sce->zeroes[w*16+g]) |
| prev = sce->sf_idx[0]; |
| if (!sce->zeroes[w*16+g]) { |
| const float *coefs = sce->coeffs + start; |
| const float *scaled = s->scoefs + start; |
| int cmb = find_min_book(maxvals[w*16+g], sce->sf_idx[w*16+g]); |
| int mindeltasf = FFMAX(0, prev - SCALE_MAX_DIFF); |
| int maxdeltasf = FFMIN(SCALE_MAX_POS - SCALE_DIV_512, prev + SCALE_MAX_DIFF); |
| if ((!cmb || dists[w*16+g] > uplims[w*16+g]) && sce->sf_idx[w*16+g] > mindeltasf) { |
| /* Try to make sure there is some energy in every nonzero band |
| * NOTE: This algorithm must be forcibly imbalanced, pushing harder |
| * on holes or more distorted bands at first, otherwise there's |
| * no net gain (since the next iteration will offset all bands |
| * on the opposite direction to compensate for extra bits) |
| */ |
| for (i = 0; i < edepth && sce->sf_idx[w*16+g] > mindeltasf; ++i) { |
| int cb, bits; |
| float dist, qenergy; |
| int mb = find_min_book(maxvals[w*16+g], sce->sf_idx[w*16+g]-1); |
| cb = find_min_book(maxvals[w*16+g], sce->sf_idx[w*16+g]); |
| dist = qenergy = 0.f; |
| bits = 0; |
| if (!cb) { |
| maxsf[w*16+g] = FFMIN(sce->sf_idx[w*16+g]-1, maxsf[w*16+g]); |
| } else if (i >= depth && dists[w*16+g] < euplims[w*16+g]) { |
| break; |
| } |
| /* !g is the DC band, it's important, since quantization error here |
| * applies to less than a cycle, it creates horrible intermodulation |
| * distortion if it doesn't stick to what psy requests |
| */ |
| if (!g && sce->ics.num_windows > 1 && dists[w*16+g] >= euplims[w*16+g]) |
| maxsf[w*16+g] = FFMIN(sce->sf_idx[w*16+g], maxsf[w*16+g]); |
| for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) { |
| int b; |
| float sqenergy; |
| 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]-1, |
| cb, |
| 1.0f, |
| INFINITY, |
| &b, &sqenergy, |
| 0); |
| bits += b; |
| qenergy += sqenergy; |
| } |
| sce->sf_idx[w*16+g]--; |
| dists[w*16+g] = dist - bits; |
| qenergies[w*16+g] = qenergy; |
| if (mb && (sce->sf_idx[w*16+g] < mindeltasf || ( |
| (dists[w*16+g] < FFMIN(uplmax*uplims[w*16+g], euplims[w*16+g])) |
| && (fabsf(qenergies[w*16+g]-energies[w*16+g]) < euplims[w*16+g]) |
| ) )) { |
| break; |
| } |
| } |
| } else if (tbits > toofewbits && sce->sf_idx[w*16+g] < FFMIN(maxdeltasf, maxsf[w*16+g]) |
| && (dists[w*16+g] < FFMIN(euplims[w*16+g], uplims[w*16+g])) |
| && (fabsf(qenergies[w*16+g]-energies[w*16+g]) < euplims[w*16+g]) |
| ) { |
| /** Um... over target. Save bits for more important stuff. */ |
| for (i = 0; i < depth && sce->sf_idx[w*16+g] < maxdeltasf; ++i) { |
| int cb, bits; |
| float dist, qenergy; |
| cb = find_min_book(maxvals[w*16+g], sce->sf_idx[w*16+g]+1); |
| if (cb > 0) { |
| dist = qenergy = 0.f; |
| bits = 0; |
| for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) { |
| int b; |
| float sqenergy; |
| 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]+1, |
| cb, |
| 1.0f, |
| INFINITY, |
| &b, &sqenergy, |
| 0); |
| bits += b; |
| qenergy += sqenergy; |
| } |
| dist -= bits; |
| if (dist < FFMIN(euplims[w*16+g], uplims[w*16+g])) { |
| sce->sf_idx[w*16+g]++; |
| dists[w*16+g] = dist; |
| qenergies[w*16+g] = qenergy; |
| } else { |
| break; |
| } |
| } else { |
| maxsf[w*16+g] = FFMIN(sce->sf_idx[w*16+g], maxsf[w*16+g]); |
| break; |
| } |
| } |
| } |
| prev = sce->sf_idx[w*16+g] = av_clip(sce->sf_idx[w*16+g], mindeltasf, maxdeltasf); |
| if (sce->sf_idx[w*16+g] != prevsc) |
| fflag = 1; |
| nminscaler = FFMIN(nminscaler, sce->sf_idx[w*16+g]); |
| sce->band_type[w*16+g] = find_min_book(maxvals[w*16+g], sce->sf_idx[w*16+g]); |
| } |
| start += sce->ics.swb_sizes[g]; |
| } |
| } |
| |
| /** SF difference limit violation risk. Must re-clamp. */ |
| prev = -1; |
| for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) { |
| for (g = 0; g < sce->ics.num_swb; g++) { |
| if (!sce->zeroes[w*16+g]) { |
| int prevsf = sce->sf_idx[w*16+g]; |
| if (prev < 0) |
| prev = prevsf; |
| sce->sf_idx[w*16+g] = av_clip(sce->sf_idx[w*16+g], prev - SCALE_MAX_DIFF, prev + SCALE_MAX_DIFF); |
| sce->band_type[w*16+g] = find_min_book(maxvals[w*16+g], sce->sf_idx[w*16+g]); |
| prev = sce->sf_idx[w*16+g]; |
| if (!fflag && prevsf != sce->sf_idx[w*16+g]) |
| fflag = 1; |
| } |
| } |
| } |
| |
| its++; |
| } while (fflag && its < maxits); |
| |
| /** Scout out next nonzero bands */ |
| ff_init_nextband_map(sce, nextband); |
| |
| prev = -1; |
| for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) { |
| /** Make sure proper codebooks are set */ |
| for (g = 0; g < sce->ics.num_swb; g++) { |
| if (!sce->zeroes[w*16+g]) { |
| sce->band_type[w*16+g] = find_min_book(maxvals[w*16+g], sce->sf_idx[w*16+g]); |
| if (sce->band_type[w*16+g] <= 0) { |
| if (!ff_sfdelta_can_remove_band(sce, nextband, prev, w*16+g)) { |
| /** Cannot zero out, make sure it's not attempted */ |
| sce->band_type[w*16+g] = 1; |
| } else { |
| sce->zeroes[w*16+g] = 1; |
| sce->band_type[w*16+g] = 0; |
| } |
| } |
| } else { |
| sce->band_type[w*16+g] = 0; |
| } |
| /** Check that there's no SF delta range violations */ |
| if (!sce->zeroes[w*16+g]) { |
| if (prev != -1) { |
| av_unused int sfdiff = sce->sf_idx[w*16+g] - prev + SCALE_DIFF_ZERO; |
| av_assert1(sfdiff >= 0 && sfdiff <= 2*SCALE_MAX_DIFF); |
| } else if (sce->zeroes[0]) { |
| /** Set global gain to something useful */ |
| sce->sf_idx[0] = sce->sf_idx[w*16+g]; |
| } |
| prev = sce->sf_idx[w*16+g]; |
| } |
| } |
| } |
| } |
| |
| #endif /* AVCODEC_AACCODER_TWOLOOP_H */ |
