484 lines · 17.9 KB · C
RawDownload
/* * Copyright (c) 2012 Andrew D'Addesio * Copyright (c) 2013-2014 Mozilla Corporation * * 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 */ #include <stdint.h> #include "celt.h"#include "pvq.h"#include "tab.h" void ff_celt_quant_bands(CeltFrame *f, OpusRangeCoder *rc){    float lowband_scratch[8 * 22];    float norm1[2 * 8 * 100];    float *norm2 = norm1 + 8 * 100;     int totalbits = (f->framebits << 3) - f->anticollapse_needed;     int update_lowband = 1;    int lowband_offset = 0;     int i, j;     for (i = f->start_band; i < f->end_band; i++) {        uint32_t cm[2] = { (1 << f->blocks) - 1, (1 << f->blocks) - 1 };        int band_offset = ff_celt_freq_bands[i] << f->size;        int band_size   = ff_celt_freq_range[i] << f->size;        float *X = f->block[0].coeffs + band_offset;        float *Y = (f->channels == 2) ? f->block[1].coeffs + band_offset : NULL;        float *norm_loc1, *norm_loc2;         int consumed = opus_rc_tell_frac(rc);        int effective_lowband = -1;        int b = 0;         /* Compute how many bits we want to allocate to this band */        if (i != f->start_band)            f->remaining -= consumed;        f->remaining2 = totalbits - consumed - 1;        if (i <= f->coded_bands - 1) {            int curr_balance = f->remaining / FFMIN(3, f->coded_bands-i);            b = av_clip_uintp2(FFMIN(f->remaining2 + 1, f->pulses[i] + curr_balance), 14);        }         if ((ff_celt_freq_bands[i] - ff_celt_freq_range[i] >= ff_celt_freq_bands[f->start_band] ||            i == f->start_band + 1) && (update_lowband || lowband_offset == 0))            lowband_offset = i;         if (i == f->start_band + 1) {            /* Special Hybrid Folding (RFC 8251 section 9). Copy the first band into            the second to ensure the second band never has to use the LCG. */            int count = (ff_celt_freq_range[i] - ff_celt_freq_range[i-1]) << f->size;             memcpy(&norm1[band_offset], &norm1[band_offset - count], count * sizeof(float));             if (f->channels == 2)                memcpy(&norm2[band_offset], &norm2[band_offset - count], count * sizeof(float));        }         /* Get a conservative estimate of the collapse_mask's for the bands we're           going to be folding from. */        if (lowband_offset != 0 && (f->spread != CELT_SPREAD_AGGRESSIVE ||                                    f->blocks > 1 || f->tf_change[i] < 0)) {            int foldstart, foldend;             /* This ensures we never repeat spectral content within one band */            effective_lowband = FFMAX(ff_celt_freq_bands[f->start_band],                                      ff_celt_freq_bands[lowband_offset] - ff_celt_freq_range[i]);            foldstart = lowband_offset;            while (ff_celt_freq_bands[--foldstart] > effective_lowband);            foldend = lowband_offset - 1;            while (++foldend < i && ff_celt_freq_bands[foldend] < effective_lowband + ff_celt_freq_range[i]);             cm[0] = cm[1] = 0;            for (j = foldstart; j < foldend; j++) {                cm[0] |= f->block[0].collapse_masks[j];                cm[1] |= f->block[f->channels - 1].collapse_masks[j];            }        }         if (f->dual_stereo && i == f->intensity_stereo) {            /* Switch off dual stereo to do intensity */            f->dual_stereo = 0;            for (j = ff_celt_freq_bands[f->start_band] << f->size; j < band_offset; j++)                norm1[j] = (norm1[j] + norm2[j]) / 2;        }         norm_loc1 = effective_lowband != -1 ? norm1 + (effective_lowband << f->size) : NULL;        norm_loc2 = effective_lowband != -1 ? norm2 + (effective_lowband << f->size) : NULL;         if (f->dual_stereo) {            cm[0] = f->pvq->quant_band(f->pvq, f, rc, i, X, NULL, band_size, b >> 1,                                       f->blocks, norm_loc1, f->size,                                       norm1 + band_offset, 0, 1.0f,                                       lowband_scratch, cm[0]);             cm[1] = f->pvq->quant_band(f->pvq, f, rc, i, Y, NULL, band_size, b >> 1,                                       f->blocks, norm_loc2, f->size,                                       norm2 + band_offset, 0, 1.0f,                                       lowband_scratch, cm[1]);        } else {            cm[0] = f->pvq->quant_band(f->pvq, f, rc, i, X,    Y, band_size, b >> 0,                                       f->blocks, norm_loc1, f->size,                                       norm1 + band_offset, 0, 1.0f,                                       lowband_scratch, cm[0] | cm[1]);            cm[1] = cm[0];        }         f->block[0].collapse_masks[i]               = (uint8_t)cm[0];        f->block[f->channels - 1].collapse_masks[i] = (uint8_t)cm[1];        f->remaining += f->pulses[i] + consumed;         /* Update the folding position only as long as we have 1 bit/sample depth */        update_lowband = (b > band_size << 3);    }} #define NORMC(bits) ((bits) << (f->channels - 1) << f->size >> 2) void ff_celt_bitalloc(CeltFrame *f, OpusRangeCoder *rc, int encode){    int i, j, low, high, total, done, bandbits, remaining, tbits_8ths;    int skip_startband      = f->start_band;    int skip_bit            = 0;    int intensitystereo_bit = 0;    int dualstereo_bit      = 0;    int dynalloc            = 6;    int extrabits           = 0;     int boost[CELT_MAX_BANDS] = { 0 };    int trim_offset[CELT_MAX_BANDS];    int threshold[CELT_MAX_BANDS];    int bits1[CELT_MAX_BANDS];    int bits2[CELT_MAX_BANDS];     /* Spread */    if (opus_rc_tell(rc) + 4 <= f->framebits) {        if (encode)            ff_opus_rc_enc_cdf(rc, f->spread, ff_celt_model_spread);        else            f->spread = ff_opus_rc_dec_cdf(rc, ff_celt_model_spread);    } else {        f->spread = CELT_SPREAD_NORMAL;    }     /* Initialize static allocation caps */    for (i = 0; i < CELT_MAX_BANDS; i++)        f->caps[i] = NORMC((ff_celt_static_caps[f->size][f->channels - 1][i] + 64) * ff_celt_freq_range[i]);     /* Band boosts */    tbits_8ths = f->framebits << 3;    for (i = f->start_band; i < f->end_band; i++) {        int quanta = ff_celt_freq_range[i] << (f->channels - 1) << f->size;        int b_dynalloc = dynalloc;        int boost_amount = f->alloc_boost[i];        quanta = FFMIN(quanta << 3, FFMAX(6 << 3, quanta));         while (opus_rc_tell_frac(rc) + (b_dynalloc << 3) < tbits_8ths && boost[i] < f->caps[i]) {            int is_boost;            if (encode) {                is_boost = boost_amount--;                ff_opus_rc_enc_log(rc, is_boost, b_dynalloc);            } else {                is_boost = ff_opus_rc_dec_log(rc, b_dynalloc);            }             if (!is_boost)                break;             boost[i]   += quanta;            tbits_8ths -= quanta;             b_dynalloc = 1;        }         if (boost[i])            dynalloc = FFMAX(dynalloc - 1, 2);    }     /* Allocation trim */    if (!encode)        f->alloc_trim = 5;    if (opus_rc_tell_frac(rc) + (6 << 3) <= tbits_8ths)        if (encode)            ff_opus_rc_enc_cdf(rc, f->alloc_trim, ff_celt_model_alloc_trim);        else            f->alloc_trim = ff_opus_rc_dec_cdf(rc, ff_celt_model_alloc_trim);     /* Anti-collapse bit reservation */    tbits_8ths = (f->framebits << 3) - opus_rc_tell_frac(rc) - 1;    f->anticollapse_needed = 0;    if (f->transient && f->size >= 2 && tbits_8ths >= ((f->size + 2) << 3))        f->anticollapse_needed = 1 << 3;    tbits_8ths -= f->anticollapse_needed;     /* Band skip bit reservation */    if (tbits_8ths >= 1 << 3)        skip_bit = 1 << 3;    tbits_8ths -= skip_bit;     /* Intensity/dual stereo bit reservation */    if (f->channels == 2) {        intensitystereo_bit = ff_celt_log2_frac[f->end_band - f->start_band];        if (intensitystereo_bit <= tbits_8ths) {            tbits_8ths -= intensitystereo_bit;            if (tbits_8ths >= 1 << 3) {                dualstereo_bit = 1 << 3;                tbits_8ths -= 1 << 3;            }        } else {            intensitystereo_bit = 0;        }    }     /* Trim offsets */    for (i = f->start_band; i < f->end_band; i++) {        int trim     = f->alloc_trim - 5 - f->size;        int band     = ff_celt_freq_range[i] * (f->end_band - i - 1);        int duration = f->size + 3;        int scale    = duration + f->channels - 1;         /* PVQ minimum allocation threshold, below this value the band is         * skipped */        threshold[i] = FFMAX(3 * ff_celt_freq_range[i] << duration >> 4,                             f->channels << 3);         trim_offset[i] = trim * (band << scale) >> 6;         if (ff_celt_freq_range[i] << f->size == 1)            trim_offset[i] -= f->channels << 3;    }     /* Bisection */    low  = 1;    high = CELT_VECTORS - 1;    while (low <= high) {        int center = (low + high) >> 1;        done = total = 0;         for (i = f->end_band - 1; i >= f->start_band; i--) {            bandbits = NORMC(ff_celt_freq_range[i] * ff_celt_static_alloc[center][i]);             if (bandbits)                bandbits = FFMAX(bandbits + trim_offset[i], 0);            bandbits += boost[i];             if (bandbits >= threshold[i] || done) {                done = 1;                total += FFMIN(bandbits, f->caps[i]);            } else if (bandbits >= f->channels << 3) {                total += f->channels << 3;            }        }         if (total > tbits_8ths)            high = center - 1;        else            low = center + 1;    }    high = low--;     /* Bisection */    for (i = f->start_band; i < f->end_band; i++) {        bits1[i] = NORMC(ff_celt_freq_range[i] * ff_celt_static_alloc[low][i]);        bits2[i] = high >= CELT_VECTORS ? f->caps[i] :                   NORMC(ff_celt_freq_range[i] * ff_celt_static_alloc[high][i]);         if (bits1[i])            bits1[i] = FFMAX(bits1[i] + trim_offset[i], 0);        if (bits2[i])            bits2[i] = FFMAX(bits2[i] + trim_offset[i], 0);         if (low)            bits1[i] += boost[i];        bits2[i] += boost[i];         if (boost[i])            skip_startband = i;        bits2[i] = FFMAX(bits2[i] - bits1[i], 0);    }     /* Bisection */    low  = 0;    high = 1 << CELT_ALLOC_STEPS;    for (i = 0; i < CELT_ALLOC_STEPS; i++) {        int center = (low + high) >> 1;        done = total = 0;         for (j = f->end_band - 1; j >= f->start_band; j--) {            bandbits = bits1[j] + (center * bits2[j] >> CELT_ALLOC_STEPS);             if (bandbits >= threshold[j] || done) {                done = 1;                total += FFMIN(bandbits, f->caps[j]);            } else if (bandbits >= f->channels << 3)                total += f->channels << 3;        }        if (total > tbits_8ths)            high = center;        else            low = center;    }     /* Bisection */    done = total = 0;    for (i = f->end_band - 1; i >= f->start_band; i--) {        bandbits = bits1[i] + (low * bits2[i] >> CELT_ALLOC_STEPS);         if (bandbits >= threshold[i] || done)            done = 1;        else            bandbits = (bandbits >= f->channels << 3) ?            f->channels << 3 : 0;         bandbits     = FFMIN(bandbits, f->caps[i]);        f->pulses[i] = bandbits;        total      += bandbits;    }     /* Band skipping */    for (f->coded_bands = f->end_band; ; f->coded_bands--) {        int allocation;        j = f->coded_bands - 1;         if (j == skip_startband) {            /* all remaining bands are not skipped */            tbits_8ths += skip_bit;            break;        }         /* determine the number of bits available for coding "do not skip" markers */        remaining   = tbits_8ths - total;        bandbits    = remaining / (ff_celt_freq_bands[j+1] - ff_celt_freq_bands[f->start_band]);        remaining  -= bandbits  * (ff_celt_freq_bands[j+1] - ff_celt_freq_bands[f->start_band]);        allocation  = f->pulses[j] + bandbits * ff_celt_freq_range[j];        allocation += FFMAX(remaining - (ff_celt_freq_bands[j] - ff_celt_freq_bands[f->start_band]), 0);         /* a "do not skip" marker is only coded if the allocation is         * above the chosen threshold */        if (allocation >= FFMAX(threshold[j], (f->channels + 1) << 3)) {            int do_not_skip;            if (encode) {                do_not_skip = f->coded_bands <= f->skip_band_floor;                ff_opus_rc_enc_log(rc, do_not_skip, 1);            } else {                do_not_skip = ff_opus_rc_dec_log(rc, 1);            }             if (do_not_skip)                break;             total      += 1 << 3;            allocation -= 1 << 3;        }         /* the band is skipped, so reclaim its bits */        total -= f->pulses[j];        if (intensitystereo_bit) {            total -= intensitystereo_bit;            intensitystereo_bit = ff_celt_log2_frac[j - f->start_band];            total += intensitystereo_bit;        }         total += f->pulses[j] = (allocation >= f->channels << 3) ? f->channels << 3 : 0;    }     /* IS start band */    if (encode) {        if (intensitystereo_bit) {            f->intensity_stereo = FFMIN(f->intensity_stereo, f->coded_bands);            ff_opus_rc_enc_uint(rc, f->intensity_stereo, f->coded_bands + 1 - f->start_band);        }    } else {        f->intensity_stereo = f->dual_stereo = 0;        if (intensitystereo_bit)            f->intensity_stereo = f->start_band + ff_opus_rc_dec_uint(rc, f->coded_bands + 1 - f->start_band);    }     /* DS flag */    if (f->intensity_stereo <= f->start_band)        tbits_8ths += dualstereo_bit; /* no intensity stereo means no dual stereo */    else if (dualstereo_bit)        if (encode)            ff_opus_rc_enc_log(rc, f->dual_stereo, 1);        else            f->dual_stereo = ff_opus_rc_dec_log(rc, 1);     /* Supply the remaining bits in this frame to lower bands */    remaining = tbits_8ths - total;    bandbits  = remaining / (ff_celt_freq_bands[f->coded_bands] - ff_celt_freq_bands[f->start_band]);    remaining -= bandbits * (ff_celt_freq_bands[f->coded_bands] - ff_celt_freq_bands[f->start_band]);    for (i = f->start_band; i < f->coded_bands; i++) {        const int bits = FFMIN(remaining, ff_celt_freq_range[i]);        f->pulses[i] += bits + bandbits * ff_celt_freq_range[i];        remaining    -= bits;    }     /* Finally determine the allocation */    for (i = f->start_band; i < f->coded_bands; i++) {        int N = ff_celt_freq_range[i] << f->size;        int prev_extra = extrabits;        f->pulses[i] += extrabits;         if (N > 1) {            int dof;        /* degrees of freedom */            int temp;       /* dof * channels * log(dof) */            int fine_bits;            int max_bits;            int offset;     /* fine energy quantization offset, i.e.                             * extra bits assigned over the standard                             * totalbits/dof */             extrabits = FFMAX(f->pulses[i] - f->caps[i], 0);            f->pulses[i] -= extrabits;             /* intensity stereo makes use of an extra degree of freedom */            dof = N * f->channels + (f->channels == 2 && N > 2 && !f->dual_stereo && i < f->intensity_stereo);            temp = dof * (ff_celt_log_freq_range[i] + (f->size << 3));            offset = (temp >> 1) - dof * CELT_FINE_OFFSET;            if (N == 2) /* dof=2 is the only case that doesn't fit the model */                offset += dof << 1;             /* grant an additional bias for the first and second pulses */            if (f->pulses[i] + offset < 2 * (dof << 3))                offset += temp >> 2;            else if (f->pulses[i] + offset < 3 * (dof << 3))                offset += temp >> 3;             fine_bits = (f->pulses[i] + offset + (dof << 2)) / (dof << 3);            max_bits  = FFMIN((f->pulses[i] >> 3) >> (f->channels - 1), CELT_MAX_FINE_BITS);            max_bits  = FFMAX(max_bits, 0);            f->fine_bits[i] = av_clip(fine_bits, 0, max_bits);             /* If fine_bits was rounded down or capped,             * give priority for the final fine energy pass */            f->fine_priority[i] = (f->fine_bits[i] * (dof << 3) >= f->pulses[i] + offset);             /* the remaining bits are assigned to PVQ */            f->pulses[i] -= f->fine_bits[i] << (f->channels - 1) << 3;        } else {            /* all bits go to fine energy except for the sign bit */            extrabits = FFMAX(f->pulses[i] - (f->channels << 3), 0);            f->pulses[i] -= extrabits;            f->fine_bits[i] = 0;            f->fine_priority[i] = 1;        }         /* hand back a limited number of extra fine energy bits to this band */        if (extrabits > 0) {            int fineextra = FFMIN(extrabits >> (f->channels + 2),                                  CELT_MAX_FINE_BITS - f->fine_bits[i]);            f->fine_bits[i] += fineextra;             fineextra <<= f->channels + 2;            f->fine_priority[i] = (fineextra >= extrabits - prev_extra);            extrabits -= fineextra;        }    }    f->remaining = extrabits;     /* skipped bands dedicate all of their bits for fine energy */    for (; i < f->end_band; i++) {        f->fine_bits[i]     = f->pulses[i] >> (f->channels - 1) >> 3;        f->pulses[i]        = 0;        f->fine_priority[i] = f->fine_bits[i] < 1;    }}

Keyboard shortcuts

General

Show keyboard shortcuts
?
Focus the current search
/

Issues and pull requests

Open filters
f

Issues, pull requests and Inbox

Select next item
j↓
Select previous item
k↑
Open selected item
Enter
Dismiss filters or clear selection
Esc

Repository code

Go to file
t