| /* |
| * AAC coefficients encoder |
| * 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 coefficients encoder |
| */ |
| |
| /*********************************** |
| * TODOs: |
| * speedup quantizer selection |
| * add sane pulse detection |
| ***********************************/ |
| |
| #include "libavutil/libm.h" // brought forward to work around cygwin header breakage |
| |
| #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" |
| #include "aacenc_utils.h" |
| #include "aacenc_quantization.h" |
| |
| #include "aacenc_is.h" |
| #include "aacenc_tns.h" |
| |
| #include "libavcodec/aaccoder_twoloop.h" |
| |
| /* Parameter of f(x) = a*(lambda/100), defines the maximum fourier spread |
| * beyond which no PNS is used (since the SFBs contain tone rather than noise) */ |
| #define NOISE_SPREAD_THRESHOLD 0.9f |
| |
| /* Parameter of f(x) = a*(100/lambda), defines how much PNS is allowed to |
| * replace low energy non zero bands */ |
| #define NOISE_LAMBDA_REPLACE 1.948f |
| |
| #include "libavcodec/aaccoder_trellis.h" |
| |
| typedef float (*quantize_and_encode_band_func)(struct AACEncContext *s, PutBitContext *pb, |
| const float *in, float *quant, const float *scaled, |
| int size, int scale_idx, int cb, |
| const float lambda, const float uplim, |
| int *bits, float *energy); |
| |
| /** |
| * Calculate rate distortion cost for quantizing with given codebook |
| * |
| * @return quantization distortion |
| */ |
| static av_always_inline float quantize_and_encode_band_cost_template( |
| struct AACEncContext *s, |
| PutBitContext *pb, const float *in, float *out, |
| const float *scaled, int size, int scale_idx, |
| int cb, const float lambda, const float uplim, |
| int *bits, float *energy, int BT_ZERO, int BT_UNSIGNED, |
| int BT_PAIR, int BT_ESC, int BT_NOISE, int BT_STEREO, |
| const float ROUNDING) |
| { |
| const int q_idx = POW_SF2_ZERO - scale_idx + SCALE_ONE_POS - SCALE_DIV_512; |
| const float Q = ff_aac_pow2sf_tab [q_idx]; |
| const float Q34 = ff_aac_pow34sf_tab[q_idx]; |
| const float IQ = ff_aac_pow2sf_tab [POW_SF2_ZERO + scale_idx - SCALE_ONE_POS + SCALE_DIV_512]; |
| const float CLIPPED_ESCAPE = 165140.0f*IQ; |
| float cost = 0; |
| float qenergy = 0; |
| const int dim = BT_PAIR ? 2 : 4; |
| int resbits = 0; |
| int off; |
| |
| if (BT_ZERO || BT_NOISE || BT_STEREO) { |
| for (int i = 0; i < size; i++) |
| cost += in[i]*in[i]; |
| if (bits) |
| *bits = 0; |
| if (energy) |
| *energy = qenergy; |
| if (out) { |
| for (int i = 0; i < size; i += dim) |
| for (int j = 0; j < dim; j++) |
| out[i+j] = 0.0f; |
| } |
| return cost * lambda; |
| } |
| if (!scaled) { |
| s->aacdsp.abs_pow34(s->scoefs, in, size); |
| scaled = s->scoefs; |
| } |
| s->aacdsp.quant_bands(s->qcoefs, in, scaled, size, !BT_UNSIGNED, aac_cb_maxval[cb], Q34, ROUNDING); |
| if (BT_UNSIGNED) { |
| off = 0; |
| } else { |
| off = aac_cb_maxval[cb]; |
| } |
| for (int i = 0; i < size; i += dim) { |
| const float *vec; |
| int *quants = s->qcoefs + i; |
| int curidx = 0; |
| int curbits; |
| float quantized, rd = 0.0f; |
| for (int j = 0; j < dim; j++) { |
| curidx *= aac_cb_range[cb]; |
| curidx += quants[j] + off; |
| } |
| curbits = ff_aac_spectral_bits[cb-1][curidx]; |
| vec = &ff_aac_codebook_vectors[cb-1][curidx*dim]; |
| if (BT_UNSIGNED) { |
| for (int j = 0; j < dim; j++) { |
| float t = fabsf(in[i+j]); |
| float di; |
| if (BT_ESC && vec[j] == 64.0f) { //FIXME: slow |
| if (t >= CLIPPED_ESCAPE) { |
| quantized = CLIPPED_ESCAPE; |
| curbits += 21; |
| } else { |
| int c = av_clip_uintp2(quant(t, Q, ROUNDING), 13); |
| quantized = c*cbrtf(c)*IQ; |
| curbits += av_log2(c)*2 - 4 + 1; |
| } |
| } else { |
| quantized = vec[j]*IQ; |
| } |
| di = t - quantized; |
| if (out) |
| out[i+j] = in[i+j] >= 0 ? quantized : -quantized; |
| if (vec[j] != 0.0f) |
| curbits++; |
| qenergy += quantized*quantized; |
| rd += di*di; |
| } |
| } else { |
| for (int j = 0; j < dim; j++) { |
| quantized = vec[j]*IQ; |
| qenergy += quantized*quantized; |
| if (out) |
| out[i+j] = quantized; |
| rd += (in[i+j] - quantized)*(in[i+j] - quantized); |
| } |
| } |
| cost += rd * lambda + curbits; |
| resbits += curbits; |
| if (cost >= uplim) |
| return uplim; |
| if (pb) { |
| put_bits(pb, ff_aac_spectral_bits[cb-1][curidx], ff_aac_spectral_codes[cb-1][curidx]); |
| if (BT_UNSIGNED) |
| for (int j = 0; j < dim; j++) |
| if (ff_aac_codebook_vectors[cb-1][curidx*dim+j] != 0.0f) |
| put_bits(pb, 1, in[i+j] < 0.0f); |
| if (BT_ESC) { |
| for (int j = 0; j < 2; j++) { |
| if (ff_aac_codebook_vectors[cb-1][curidx*2+j] == 64.0f) { |
| int coef = av_clip_uintp2(quant(fabsf(in[i+j]), Q, ROUNDING), 13); |
| int len = av_log2(coef); |
| |
| put_bits(pb, len - 4 + 1, (1 << (len - 4 + 1)) - 2); |
| put_sbits(pb, len, coef); |
| } |
| } |
| } |
| } |
| } |
| |
| if (bits) |
| *bits = resbits; |
| if (energy) |
| *energy = qenergy; |
| return cost; |
| } |
| |
| static inline float quantize_and_encode_band_cost_NONE(struct AACEncContext *s, PutBitContext *pb, |
| const float *in, float *quant, const float *scaled, |
| int size, int scale_idx, int cb, |
| const float lambda, const float uplim, |
| int *bits, float *energy) { |
| av_assert0(0); |
| return 0.0f; |
| } |
| |
| #define QUANTIZE_AND_ENCODE_BAND_COST_FUNC(NAME, BT_ZERO, BT_UNSIGNED, BT_PAIR, BT_ESC, BT_NOISE, BT_STEREO, ROUNDING) \ |
| static float quantize_and_encode_band_cost_ ## NAME( \ |
| struct AACEncContext *s, \ |
| PutBitContext *pb, const float *in, float *quant, \ |
| const float *scaled, int size, int scale_idx, \ |
| int cb, const float lambda, const float uplim, \ |
| int *bits, float *energy) { \ |
| return quantize_and_encode_band_cost_template( \ |
| s, pb, in, quant, scaled, size, scale_idx, \ |
| BT_ESC ? ESC_BT : cb, lambda, uplim, bits, energy, \ |
| BT_ZERO, BT_UNSIGNED, BT_PAIR, BT_ESC, BT_NOISE, BT_STEREO, \ |
| ROUNDING); \ |
| } |
| |
| QUANTIZE_AND_ENCODE_BAND_COST_FUNC(ZERO, 1, 0, 0, 0, 0, 0, ROUND_STANDARD) |
| QUANTIZE_AND_ENCODE_BAND_COST_FUNC(SQUAD, 0, 0, 0, 0, 0, 0, ROUND_STANDARD) |
| QUANTIZE_AND_ENCODE_BAND_COST_FUNC(UQUAD, 0, 1, 0, 0, 0, 0, ROUND_STANDARD) |
| QUANTIZE_AND_ENCODE_BAND_COST_FUNC(SPAIR, 0, 0, 1, 0, 0, 0, ROUND_STANDARD) |
| QUANTIZE_AND_ENCODE_BAND_COST_FUNC(UPAIR, 0, 1, 1, 0, 0, 0, ROUND_STANDARD) |
| QUANTIZE_AND_ENCODE_BAND_COST_FUNC(ESC, 0, 1, 1, 1, 0, 0, ROUND_STANDARD) |
| QUANTIZE_AND_ENCODE_BAND_COST_FUNC(ESC_RTZ, 0, 1, 1, 1, 0, 0, ROUND_TO_ZERO) |
| QUANTIZE_AND_ENCODE_BAND_COST_FUNC(NOISE, 0, 0, 0, 0, 1, 0, ROUND_STANDARD) |
| QUANTIZE_AND_ENCODE_BAND_COST_FUNC(STEREO,0, 0, 0, 0, 0, 1, ROUND_STANDARD) |
| |
| static const quantize_and_encode_band_func quantize_and_encode_band_cost_arr[] = |
| { |
| quantize_and_encode_band_cost_ZERO, |
| quantize_and_encode_band_cost_SQUAD, |
| quantize_and_encode_band_cost_SQUAD, |
| quantize_and_encode_band_cost_UQUAD, |
| quantize_and_encode_band_cost_UQUAD, |
| quantize_and_encode_band_cost_SPAIR, |
| quantize_and_encode_band_cost_SPAIR, |
| quantize_and_encode_band_cost_UPAIR, |
| quantize_and_encode_band_cost_UPAIR, |
| quantize_and_encode_band_cost_UPAIR, |
| quantize_and_encode_band_cost_UPAIR, |
| quantize_and_encode_band_cost_ESC, |
| quantize_and_encode_band_cost_NONE, /* CB 12 doesn't exist */ |
| quantize_and_encode_band_cost_NOISE, |
| quantize_and_encode_band_cost_STEREO, |
| quantize_and_encode_band_cost_STEREO, |
| }; |
| |
| static const quantize_and_encode_band_func quantize_and_encode_band_cost_rtz_arr[] = |
| { |
| quantize_and_encode_band_cost_ZERO, |
| quantize_and_encode_band_cost_SQUAD, |
| quantize_and_encode_band_cost_SQUAD, |
| quantize_and_encode_band_cost_UQUAD, |
| quantize_and_encode_band_cost_UQUAD, |
| quantize_and_encode_band_cost_SPAIR, |
| quantize_and_encode_band_cost_SPAIR, |
| quantize_and_encode_band_cost_UPAIR, |
| quantize_and_encode_band_cost_UPAIR, |
| quantize_and_encode_band_cost_UPAIR, |
| quantize_and_encode_band_cost_UPAIR, |
| quantize_and_encode_band_cost_ESC_RTZ, |
| quantize_and_encode_band_cost_NONE, /* CB 12 doesn't exist */ |
| quantize_and_encode_band_cost_NOISE, |
| quantize_and_encode_band_cost_STEREO, |
| quantize_and_encode_band_cost_STEREO, |
| }; |
| |
| float ff_quantize_and_encode_band_cost(struct AACEncContext *s, PutBitContext *pb, |
| const float *in, float *quant, const float *scaled, |
| int size, int scale_idx, int cb, |
| const float lambda, const float uplim, |
| int *bits, float *energy) |
| { |
| return quantize_and_encode_band_cost_arr[cb](s, pb, in, quant, scaled, size, |
| scale_idx, cb, lambda, uplim, |
| bits, energy); |
| } |
| |
| static inline void quantize_and_encode_band(struct AACEncContext *s, PutBitContext *pb, |
| const float *in, float *out, int size, int scale_idx, |
| int cb, const float lambda, int rtz) |
| { |
| (rtz ? quantize_and_encode_band_cost_rtz_arr : quantize_and_encode_band_cost_arr)[cb](s, pb, in, out, NULL, size, scale_idx, cb, |
| lambda, INFINITY, NULL, NULL); |
| } |
| |
| /** |
| * structure used in optimal codebook search |
| */ |
| typedef struct BandCodingPath { |
| int prev_idx; ///< pointer to the previous path point |
| float cost; ///< path cost |
| int run; |
| } BandCodingPath; |
| |
| typedef struct TrellisPath { |
| float cost; |
| int prev; |
| } TrellisPath; |
| |
| #define TRELLIS_STAGES 121 |
| #define TRELLIS_STATES (SCALE_MAX_DIFF+1) |
| |
| static void set_special_band_scalefactors(AACEncContext *s, SingleChannelElement *sce) |
| { |
| int w, g; |
| int prevscaler_n = -255, prevscaler_i = 0; |
| int bands = 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]) |
| continue; |
| if (sce->band_type[w*16+g] == INTENSITY_BT || sce->band_type[w*16+g] == INTENSITY_BT2) { |
| sce->sf_idx[w*16+g] = av_clip(roundf(log2f(sce->is_ener[w*16+g])*2), -155, 100); |
| bands++; |
| } else if (sce->band_type[w*16+g] == NOISE_BT) { |
| sce->sf_idx[w*16+g] = av_clip(3+ceilf(log2f(sce->pns_ener[w*16+g])*2), -100, 155); |
| if (prevscaler_n == -255) |
| prevscaler_n = sce->sf_idx[w*16+g]; |
| bands++; |
| } |
| } |
| } |
| |
| if (!bands) |
| return; |
| |
| /* Clip the scalefactor indices */ |
| 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]) |
| continue; |
| if (sce->band_type[w*16+g] == INTENSITY_BT || sce->band_type[w*16+g] == INTENSITY_BT2) { |
| 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); |
| } else if (sce->band_type[w*16+g] == NOISE_BT) { |
| 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); |
| } |
| } |
| } |
| } |
| |
| static void search_for_quantizers_fast(AVCodecContext *avctx, AACEncContext *s, |
| SingleChannelElement *sce, |
| const float lambda) |
| { |
| int start = 0, i, w, w2, g; |
| int destbits = avctx->bit_rate * 1024.0 / avctx->sample_rate / avctx->ch_layout.nb_channels * (lambda / 120.f); |
| float dists[128] = { 0 }, uplims[128] = { 0 }; |
| float maxvals[128]; |
| int fflag, minscaler; |
| int its = 0; |
| int allz = 0; |
| float minthr = INFINITY; |
| |
| // 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); |
| //some heuristic to determine initial quantizers will reduce search time |
| //determine zero bands and upper limits |
| for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) { |
| start = 0; |
| for (g = 0; g < sce->ics.num_swb; g++) { |
| int nz = 0; |
| float uplim = 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]; |
| uplim += band->threshold; |
| if (band->energy <= band->threshold || band->threshold == 0.0f) { |
| sce->zeroes[(w+w2)*16+g] = 1; |
| continue; |
| } |
| nz = 1; |
| } |
| uplims[w*16+g] = uplim *512; |
| sce->band_type[w*16+g] = 0; |
| sce->zeroes[w*16+g] = !nz; |
| if (nz) |
| minthr = FFMIN(minthr, uplim); |
| allz |= nz; |
| start += sce->ics.swb_sizes[g]; |
| } |
| } |
| 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; |
| } |
| sce->sf_idx[w*16+g] = SCALE_ONE_POS + FFMIN(log2f(uplims[w*16+g]/minthr)*4,59); |
| } |
| } |
| |
| if (!allz) |
| return; |
| s->aacdsp.abs_pow34(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]; |
| } |
| } |
| |
| //perform two-loop search |
| //outer loop - improve quality |
| do { |
| int tbits, qstep; |
| minscaler = sce->sf_idx[0]; |
| //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->ch_layout.nb_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->ch_layout.nb_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->aacdsp.abs_pow34(NOR34, &sce->coeffs[start_c], sce->ics.swb_sizes[g]); |
| s->aacdsp.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); |
| /* 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->ch_layout.nb_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->ch_layout.nb_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->aacdsp.abs_pow34(M34, M, sce0->ics.swb_sizes[g]); |
| s->aacdsp.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->aacdsp.abs_pow34(L34, sce0->coeffs+start+(w+w2)*128, sce0->ics.swb_sizes[g]); |
| s->aacdsp.abs_pow34(R34, sce1->coeffs+start+(w+w2)*128, sce0->ics.swb_sizes[g]); |
| s->aacdsp.abs_pow34(M34, M, sce0->ics.swb_sizes[g]); |
| s->aacdsp.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); |
| 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); |
| dist2 += quantize_band_cost(s, M, |
| M34, |
| sce0->ics.swb_sizes[g], |
| mididx, |
| midcb, |
| lambda / (minthr + FLT_MIN), INFINITY, &b3, NULL); |
| dist2 += quantize_band_cost(s, S, |
| S34, |
| sce1->ics.swb_sizes[g], |
| sididx, |
| sidcb, |
| mslambda / (minthr * bmax + FLT_MIN), INFINITY, &b4, NULL); |
| 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_TWOLOOP] = { |
| search_for_quantizers_twoloop, |
| codebook_trellis_rate, |
| quantize_and_encode_band, |
| ff_aac_encode_tns_info, |
| ff_aac_apply_tns, |
| set_special_band_scalefactors, |
| search_for_pns, |
| mark_pns, |
| ff_aac_search_for_tns, |
| search_for_ms, |
| ff_aac_search_for_is, |
| }, |
| [AAC_CODER_FAST] = { |
| search_for_quantizers_fast, |
| codebook_trellis_rate, |
| quantize_and_encode_band, |
| ff_aac_encode_tns_info, |
| ff_aac_apply_tns, |
| set_special_band_scalefactors, |
| search_for_pns, |
| mark_pns, |
| ff_aac_search_for_tns, |
| search_for_ms, |
| ff_aac_search_for_is, |
| }, |
| }; |
