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FFmpeg/libavcodec/aacenc_is.c

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aaccoder: move the Intensity Stereo implementation out This commit moves the intensity stereo implementation out from aaccoder and into a separate file. This was possible using the previous commits. This commit also drastically improves the IS implementation by making it phase invariant e.g. it will always choose the best possible phase regardless of whether M/S coding is on or most of the coefficients have identical phases. This also increases the quality and reduces any distortions introduced by enablind intensity stereo. Users are encouraged to test it out using the -aac_is 1 parameter as it has always been. Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2015-08-21 20:13:26 +02:00
/*
* AAC encoder intensity stereo
* Copyright (C) 2015 Rostislav Pehlivanov
*
* 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 Intensity Stereo
* @author Rostislav Pehlivanov ( atomnuker gmail com )
*/
#include "aacenc.h"
#include "aacenc_utils.h"
#include "aacenc_is.h"
#include "aacenc_quantization.h"
aacenc_is: rename struct to follow guidelines Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2015-08-22 07:47:14 +02:00
struct AACISError ff_aac_is_encoding_err(AACEncContext *s, ChannelElement *cpe,
int start, int w, int g, float ener0,
aacenc_is: add a flag to use pure coefficients instead This commit adds a flag to use the pure coefficients instead of the processed ones (sce->coeffs). This is needed because IS will apply the changes to the coefficients immediately before the adjust_common_prediction function and it doesn't make sense to measure stereo channel coefficient difference when one of the channels coefficients are all zero. Therefore add a flag to use pure coefficients in that case. TNS is the only thing touching the coefficients before IS so common window prediction will not take that into account but the effect of the TNS filter per coefficient can be small (a few percent) so to some approximation it's fine to just ignore that. Also fixed a small error which doesn't alter the results that much. pow(sqrt(number), 3.0/4.0) == pow(number, 3.0/8.0) != pow(number, 3.0/4.0). Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2015-09-05 09:32:09 +02:00
float ener1, float ener01,
int use_pcoeffs, int phase)
aaccoder: move the Intensity Stereo implementation out This commit moves the intensity stereo implementation out from aaccoder and into a separate file. This was possible using the previous commits. This commit also drastically improves the IS implementation by making it phase invariant e.g. it will always choose the best possible phase regardless of whether M/S coding is on or most of the coefficients have identical phases. This also increases the quality and reduces any distortions introduced by enablind intensity stereo. Users are encouraged to test it out using the -aac_is 1 parameter as it has always been. Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2015-08-21 20:13:26 +02:00
{
int i, w2;
aacenc_is: add a flag to use pure coefficients instead This commit adds a flag to use the pure coefficients instead of the processed ones (sce->coeffs). This is needed because IS will apply the changes to the coefficients immediately before the adjust_common_prediction function and it doesn't make sense to measure stereo channel coefficient difference when one of the channels coefficients are all zero. Therefore add a flag to use pure coefficients in that case. TNS is the only thing touching the coefficients before IS so common window prediction will not take that into account but the effect of the TNS filter per coefficient can be small (a few percent) so to some approximation it's fine to just ignore that. Also fixed a small error which doesn't alter the results that much. pow(sqrt(number), 3.0/4.0) == pow(number, 3.0/8.0) != pow(number, 3.0/4.0). Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2015-09-05 09:32:09 +02:00
SingleChannelElement *sce0 = &cpe->ch[0];
SingleChannelElement *sce1 = &cpe->ch[1];
float *L = use_pcoeffs ? sce0->pcoeffs : sce0->coeffs;
float *R = use_pcoeffs ? sce1->pcoeffs : sce1->coeffs;
aaccoder: move the Intensity Stereo implementation out This commit moves the intensity stereo implementation out from aaccoder and into a separate file. This was possible using the previous commits. This commit also drastically improves the IS implementation by making it phase invariant e.g. it will always choose the best possible phase regardless of whether M/S coding is on or most of the coefficients have identical phases. This also increases the quality and reduces any distortions introduced by enablind intensity stereo. Users are encouraged to test it out using the -aac_is 1 parameter as it has always been. Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2015-08-21 20:13:26 +02:00
float *L34 = &s->scoefs[256*0], *R34 = &s->scoefs[256*1];
float *IS = &s->scoefs[256*2], *I34 = &s->scoefs[256*3];
float dist1 = 0.0f, dist2 = 0.0f;
aacenc_is: rename struct to follow guidelines Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2015-08-22 07:47:14 +02:00
struct AACISError is_error = {0};
aaccoder: move the Intensity Stereo implementation out This commit moves the intensity stereo implementation out from aaccoder and into a separate file. This was possible using the previous commits. This commit also drastically improves the IS implementation by making it phase invariant e.g. it will always choose the best possible phase regardless of whether M/S coding is on or most of the coefficients have identical phases. This also increases the quality and reduces any distortions introduced by enablind intensity stereo. Users are encouraged to test it out using the -aac_is 1 parameter as it has always been. Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2015-08-21 20:13:26 +02:00
AAC encoder: Extensive improvements This finalizes merging of the work in the patches in ticket #2686. Improvements to twoloop and RC logic are extensive. The non-exhaustive list of twoloop improvments includes: - Tweaks to distortion limits on the RD optimization phase of twoloop - Deeper search in twoloop - PNS information marking to let twoloop decide when to use it (turned out having the decision made separately wasn't working) - Tonal band detection and priorization - Better band energy conservation rules - Strict hole avoidance For rate control: - Use psymodel's bit allocation to allow proper use of the bit reservoir. Don't work against the bit reservoir by moving lambda in the opposite direction when psymodel decides to allocate more/less bits to a frame. - Retry the encode if the effective rate lies outside a reasonable margin of psymodel's allocation or the selected ABR. - Log average lambda at the end. Useful info for everyone, but especially for tuning of the various encoder constants that relate to lambda feedback. Psy: - Do not apply lowpass with a FIR filter, instead just let the coder zero bands above the cutoff. The FIR filter induces group delay, and while zeroing bands causes ripple, it's lost in the quantization noise. - Experimental VBR bit allocation code - Tweak automatic lowpass filter threshold to maximize audio bandwidth at all bitrates while still providing acceptable, stable quality. I/S: - Phase decision fixes. Unrelated to #2686, but the bugs only surfaced when the merge was finalized. Measure I/S band energy accounting for phase, and prevent I/S and M/S from being applied both. PNS: - Avoid marking short bands with PNS when they're part of a window group in which there's a large variation of energy from one window to the next. PNS can't preserve those and the effect is extremely noticeable. M/S: - Implement BMLD protection similar to the specified in ISO-IEC/13818:7-2003, Appendix C Section 6.1. Since M/S decision doesn't conform to section 6.1, a different method had to be implemented, but should provide equivalent protection. - Move the decision logic closer to the method specified in ISO-IEC/13818:7-2003, Appendix C Section 6.1. Specifically, make sure M/S needs less bits than dual stereo. - Don't apply M/S in bands that are using I/S Now, this of course needed adjustments in the compare targets and fuzz factors of the AAC encoder's fate tests, but if wondering why the targets go up (more distortion), consider the previous coder was using too many bits on LF content (far more than required by psy), and thus those signals will now be more distorted, not less. The extra distortion isn't audible though, I carried extensive ABX testing to make sure. A very similar patch was also extensively tested by Kamendo2 in the context of #2686.
2015-10-11 22:29:50 +02:00
if (ener01 <= 0 || ener0 <= 0) {
is_error.pass = 0;
return is_error;
}
aaccoder: move the Intensity Stereo implementation out This commit moves the intensity stereo implementation out from aaccoder and into a separate file. This was possible using the previous commits. This commit also drastically improves the IS implementation by making it phase invariant e.g. it will always choose the best possible phase regardless of whether M/S coding is on or most of the coefficients have identical phases. This also increases the quality and reduces any distortions introduced by enablind intensity stereo. Users are encouraged to test it out using the -aac_is 1 parameter as it has always been. Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2015-08-21 20:13:26 +02:00
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];
AAC encoder: in IS, fix index of sf_idx, band_type Correct addressing of sf_idx and band_type arrays in I/S code. Both arrays don't guarantee valid values for subwindows at all times, depending on which coder is being used, which could result in reading of garbage values. Instead, only the first subwindow in the window group has to be used, ie: use w*16+g instead of (w+w2)*16+g
2016-01-08 10:16:18 +02:00
int is_band_type, is_sf_idx = FFMAX(1, sce0->sf_idx[w*16+g]-4);
avcodec/aacenc_is: replace pow(x, 0.75) by x/sqrtf(sqrtf(x)) This is quite an accurate approximation; testing shows ~ 2ulp error in the floating point result. Tested with FATE. Alternatively, if one wants "full accuracy", one can use powf, or sqrt instead of sqrtf. With powf, one gets 1 ulp error (theoretically should be 0, as 0.75 is exactly representable) on GNU libm, with sqrt, 0 ulp error. Signed-off-by: Ganesh Ajjanagadde <gajjanagadde@gmail.com> Abstracted into pos_pow34 utility function Signed-off-by: Claudio Freire <klaussfreire@gmail.com>
2016-01-14 05:38:22 +02:00
float e01_34 = phase*pos_pow34(ener1/ener0);
aaccoder: move the Intensity Stereo implementation out This commit moves the intensity stereo implementation out from aaccoder and into a separate file. This was possible using the previous commits. This commit also drastically improves the IS implementation by making it phase invariant e.g. it will always choose the best possible phase regardless of whether M/S coding is on or most of the coefficients have identical phases. This also increases the quality and reduces any distortions introduced by enablind intensity stereo. Users are encouraged to test it out using the -aac_is 1 parameter as it has always been. Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2015-08-21 20:13:26 +02:00
float maxval, dist_spec_err = 0.0f;
float minthr = FFMIN(band0->threshold, band1->threshold);
aacenc_is: add a flag to use pure coefficients instead This commit adds a flag to use the pure coefficients instead of the processed ones (sce->coeffs). This is needed because IS will apply the changes to the coefficients immediately before the adjust_common_prediction function and it doesn't make sense to measure stereo channel coefficient difference when one of the channels coefficients are all zero. Therefore add a flag to use pure coefficients in that case. TNS is the only thing touching the coefficients before IS so common window prediction will not take that into account but the effect of the TNS filter per coefficient can be small (a few percent) so to some approximation it's fine to just ignore that. Also fixed a small error which doesn't alter the results that much. pow(sqrt(number), 3.0/4.0) == pow(number, 3.0/8.0) != pow(number, 3.0/4.0). Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2015-09-05 09:32:09 +02:00
for (i = 0; i < sce0->ics.swb_sizes[g]; i++)
IS[i] = (L[start+(w+w2)*128+i] + phase*R[start+(w+w2)*128+i])*sqrt(ener0/ener01);
aacenc: add SIMD optimizations for abs_pow34 and quantization Performance improvements: quant_bands: with: 681 decicycles in quant_bands, 8388453 runs, 155 skips without: 1190 decicycles in quant_bands, 8388386 runs, 222 skips Around 42% for the function Twoloop coder: abs_pow34: with/without: 7.82s/8.17s Around 4% for the entire encoder Both: with/without: 7.15s/8.17s Around 12% for the entire encoder Fast coder: abs_pow34: with/without: 3.40s/3.77s Around 10% for the entire encoder Both: with/without: 3.02s/3.77s Around 20% faster for the entire encoder Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com> Tested-by: Michael Niedermayer <michael@niedermayer.cc> Reviewed-by: James Almer <jamrial@gmail.com>
2016-10-08 16:59:14 +02:00
s->abs_pow34(L34, &L[start+(w+w2)*128], sce0->ics.swb_sizes[g]);
s->abs_pow34(R34, &R[start+(w+w2)*128], sce0->ics.swb_sizes[g]);
s->abs_pow34(I34, IS, sce0->ics.swb_sizes[g]);
aaccoder: move the Intensity Stereo implementation out This commit moves the intensity stereo implementation out from aaccoder and into a separate file. This was possible using the previous commits. This commit also drastically improves the IS implementation by making it phase invariant e.g. it will always choose the best possible phase regardless of whether M/S coding is on or most of the coefficients have identical phases. This also increases the quality and reduces any distortions introduced by enablind intensity stereo. Users are encouraged to test it out using the -aac_is 1 parameter as it has always been. Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2015-08-21 20:13:26 +02:00
maxval = find_max_val(1, sce0->ics.swb_sizes[g], I34);
is_band_type = find_min_book(maxval, is_sf_idx);
aacenc_is: add a flag to use pure coefficients instead This commit adds a flag to use the pure coefficients instead of the processed ones (sce->coeffs). This is needed because IS will apply the changes to the coefficients immediately before the adjust_common_prediction function and it doesn't make sense to measure stereo channel coefficient difference when one of the channels coefficients are all zero. Therefore add a flag to use pure coefficients in that case. TNS is the only thing touching the coefficients before IS so common window prediction will not take that into account but the effect of the TNS filter per coefficient can be small (a few percent) so to some approximation it's fine to just ignore that. Also fixed a small error which doesn't alter the results that much. pow(sqrt(number), 3.0/4.0) == pow(number, 3.0/8.0) != pow(number, 3.0/4.0). Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2015-09-05 09:32:09 +02:00
dist1 += quantize_band_cost(s, &L[start + (w+w2)*128], L34,
aaccoder: move the Intensity Stereo implementation out This commit moves the intensity stereo implementation out from aaccoder and into a separate file. This was possible using the previous commits. This commit also drastically improves the IS implementation by making it phase invariant e.g. it will always choose the best possible phase regardless of whether M/S coding is on or most of the coefficients have identical phases. This also increases the quality and reduces any distortions introduced by enablind intensity stereo. Users are encouraged to test it out using the -aac_is 1 parameter as it has always been. Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2015-08-21 20:13:26 +02:00
sce0->ics.swb_sizes[g],
AAC encoder: in IS, fix index of sf_idx, band_type Correct addressing of sf_idx and band_type arrays in I/S code. Both arrays don't guarantee valid values for subwindows at all times, depending on which coder is being used, which could result in reading of garbage values. Instead, only the first subwindow in the window group has to be used, ie: use w*16+g instead of (w+w2)*16+g
2016-01-08 10:16:18 +02:00
sce0->sf_idx[w*16+g],
sce0->band_type[w*16+g],
avcodec/aacenc_quantization: Remove always-zero function parameter rtz is only ever nonzero for quantize_and_encode_band(). Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2022-08-01 09:45:10 +02:00
s->lambda / band0->threshold, INFINITY, NULL, NULL);
aacenc_is: add a flag to use pure coefficients instead This commit adds a flag to use the pure coefficients instead of the processed ones (sce->coeffs). This is needed because IS will apply the changes to the coefficients immediately before the adjust_common_prediction function and it doesn't make sense to measure stereo channel coefficient difference when one of the channels coefficients are all zero. Therefore add a flag to use pure coefficients in that case. TNS is the only thing touching the coefficients before IS so common window prediction will not take that into account but the effect of the TNS filter per coefficient can be small (a few percent) so to some approximation it's fine to just ignore that. Also fixed a small error which doesn't alter the results that much. pow(sqrt(number), 3.0/4.0) == pow(number, 3.0/8.0) != pow(number, 3.0/4.0). Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2015-09-05 09:32:09 +02:00
dist1 += quantize_band_cost(s, &R[start + (w+w2)*128], R34,
aaccoder: move the Intensity Stereo implementation out This commit moves the intensity stereo implementation out from aaccoder and into a separate file. This was possible using the previous commits. This commit also drastically improves the IS implementation by making it phase invariant e.g. it will always choose the best possible phase regardless of whether M/S coding is on or most of the coefficients have identical phases. This also increases the quality and reduces any distortions introduced by enablind intensity stereo. Users are encouraged to test it out using the -aac_is 1 parameter as it has always been. Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2015-08-21 20:13:26 +02:00
sce1->ics.swb_sizes[g],
AAC encoder: in IS, fix index of sf_idx, band_type Correct addressing of sf_idx and band_type arrays in I/S code. Both arrays don't guarantee valid values for subwindows at all times, depending on which coder is being used, which could result in reading of garbage values. Instead, only the first subwindow in the window group has to be used, ie: use w*16+g instead of (w+w2)*16+g
2016-01-08 10:16:18 +02:00
sce1->sf_idx[w*16+g],
sce1->band_type[w*16+g],
avcodec/aacenc_quantization: Remove always-zero function parameter rtz is only ever nonzero for quantize_and_encode_band(). Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2022-08-01 09:45:10 +02:00
s->lambda / band1->threshold, INFINITY, NULL, NULL);
aaccoder: move the Intensity Stereo implementation out This commit moves the intensity stereo implementation out from aaccoder and into a separate file. This was possible using the previous commits. This commit also drastically improves the IS implementation by making it phase invariant e.g. it will always choose the best possible phase regardless of whether M/S coding is on or most of the coefficients have identical phases. This also increases the quality and reduces any distortions introduced by enablind intensity stereo. Users are encouraged to test it out using the -aac_is 1 parameter as it has always been. Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2015-08-21 20:13:26 +02:00
dist2 += quantize_band_cost(s, IS, I34, sce0->ics.swb_sizes[g],
is_sf_idx, is_band_type,
avcodec/aacenc_quantization: Remove always-zero function parameter rtz is only ever nonzero for quantize_and_encode_band(). Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2022-08-01 09:45:10 +02:00
s->lambda / minthr, INFINITY, NULL, NULL);
aaccoder: move the Intensity Stereo implementation out This commit moves the intensity stereo implementation out from aaccoder and into a separate file. This was possible using the previous commits. This commit also drastically improves the IS implementation by making it phase invariant e.g. it will always choose the best possible phase regardless of whether M/S coding is on or most of the coefficients have identical phases. This also increases the quality and reduces any distortions introduced by enablind intensity stereo. Users are encouraged to test it out using the -aac_is 1 parameter as it has always been. Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2015-08-21 20:13:26 +02:00
for (i = 0; i < sce0->ics.swb_sizes[g]; i++) {
dist_spec_err += (L34[i] - I34[i])*(L34[i] - I34[i]);
dist_spec_err += (R34[i] - I34[i]*e01_34)*(R34[i] - I34[i]*e01_34);
}
dist_spec_err *= s->lambda / minthr;
dist2 += dist_spec_err;
}
is_error.pass = dist2 <= dist1;
is_error.phase = phase;
AAC encoder: fix I/S relative error evaluation The relative error between two encoding strategies is the simple difference of rate-distortion values, and not the absolute difference. An absolute measure would allow worsening of the quantization error as well as improving.
2016-01-08 11:18:24 +02:00
is_error.error = dist2 - dist1;
aaccoder: move the Intensity Stereo implementation out This commit moves the intensity stereo implementation out from aaccoder and into a separate file. This was possible using the previous commits. This commit also drastically improves the IS implementation by making it phase invariant e.g. it will always choose the best possible phase regardless of whether M/S coding is on or most of the coefficients have identical phases. This also increases the quality and reduces any distortions introduced by enablind intensity stereo. Users are encouraged to test it out using the -aac_is 1 parameter as it has always been. Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2015-08-21 20:13:26 +02:00
is_error.dist1 = dist1;
is_error.dist2 = dist2;
AAC encoder: Extensive improvements This finalizes merging of the work in the patches in ticket #2686. Improvements to twoloop and RC logic are extensive. The non-exhaustive list of twoloop improvments includes: - Tweaks to distortion limits on the RD optimization phase of twoloop - Deeper search in twoloop - PNS information marking to let twoloop decide when to use it (turned out having the decision made separately wasn't working) - Tonal band detection and priorization - Better band energy conservation rules - Strict hole avoidance For rate control: - Use psymodel's bit allocation to allow proper use of the bit reservoir. Don't work against the bit reservoir by moving lambda in the opposite direction when psymodel decides to allocate more/less bits to a frame. - Retry the encode if the effective rate lies outside a reasonable margin of psymodel's allocation or the selected ABR. - Log average lambda at the end. Useful info for everyone, but especially for tuning of the various encoder constants that relate to lambda feedback. Psy: - Do not apply lowpass with a FIR filter, instead just let the coder zero bands above the cutoff. The FIR filter induces group delay, and while zeroing bands causes ripple, it's lost in the quantization noise. - Experimental VBR bit allocation code - Tweak automatic lowpass filter threshold to maximize audio bandwidth at all bitrates while still providing acceptable, stable quality. I/S: - Phase decision fixes. Unrelated to #2686, but the bugs only surfaced when the merge was finalized. Measure I/S band energy accounting for phase, and prevent I/S and M/S from being applied both. PNS: - Avoid marking short bands with PNS when they're part of a window group in which there's a large variation of energy from one window to the next. PNS can't preserve those and the effect is extremely noticeable. M/S: - Implement BMLD protection similar to the specified in ISO-IEC/13818:7-2003, Appendix C Section 6.1. Since M/S decision doesn't conform to section 6.1, a different method had to be implemented, but should provide equivalent protection. - Move the decision logic closer to the method specified in ISO-IEC/13818:7-2003, Appendix C Section 6.1. Specifically, make sure M/S needs less bits than dual stereo. - Don't apply M/S in bands that are using I/S Now, this of course needed adjustments in the compare targets and fuzz factors of the AAC encoder's fate tests, but if wondering why the targets go up (more distortion), consider the previous coder was using too many bits on LF content (far more than required by psy), and thus those signals will now be more distorted, not less. The extra distortion isn't audible though, I carried extensive ABX testing to make sure. A very similar patch was also extensively tested by Kamendo2 in the context of #2686.
2015-10-11 22:29:50 +02:00
is_error.ener01 = ener01;
aaccoder: move the Intensity Stereo implementation out This commit moves the intensity stereo implementation out from aaccoder and into a separate file. This was possible using the previous commits. This commit also drastically improves the IS implementation by making it phase invariant e.g. it will always choose the best possible phase regardless of whether M/S coding is on or most of the coefficients have identical phases. This also increases the quality and reduces any distortions introduced by enablind intensity stereo. Users are encouraged to test it out using the -aac_is 1 parameter as it has always been. Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2015-08-21 20:13:26 +02:00
return is_error;
}
aacenc: Add missing ff_ prefixes Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com> Reviewed-by: Ganesh Ajjanagadde <gajjanag@mit.edu>
2015-08-22 07:11:23 +02:00
void ff_aac_search_for_is(AACEncContext *s, AVCodecContext *avctx, ChannelElement *cpe)
aaccoder: move the Intensity Stereo implementation out This commit moves the intensity stereo implementation out from aaccoder and into a separate file. This was possible using the previous commits. This commit also drastically improves the IS implementation by making it phase invariant e.g. it will always choose the best possible phase regardless of whether M/S coding is on or most of the coefficients have identical phases. This also increases the quality and reduces any distortions introduced by enablind intensity stereo. Users are encouraged to test it out using the -aac_is 1 parameter as it has always been. Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2015-08-21 20:13:26 +02:00
{
SingleChannelElement *sce0 = &cpe->ch[0];
SingleChannelElement *sce1 = &cpe->ch[1];
AAC encoder: encode out-of-phase I/S efficiently Use the ability to invert phase with ms_mask instead of changing the codebook when possible, to avoid having to switch codebooks if some bands are INTENSTY_BT and others are INTENSITY_BT2, since usually a set ms_mask uses less bits that a codebook change. While it may not always be a win (ie: if it causes an ms_mask bitmap to be sent when it wouldn't have been otherwise), it's unlikely since the ms_mask bitmap will almost always be there already for M/S itself.
2016-01-10 08:04:21 +02:00
int start = 0, count = 0, w, w2, g, i, prev_sf1 = -1, prev_bt = -1, prev_is = 0;
aaccoder: move the Intensity Stereo implementation out This commit moves the intensity stereo implementation out from aaccoder and into a separate file. This was possible using the previous commits. This commit also drastically improves the IS implementation by making it phase invariant e.g. it will always choose the best possible phase regardless of whether M/S coding is on or most of the coefficients have identical phases. This also increases the quality and reduces any distortions introduced by enablind intensity stereo. Users are encouraged to test it out using the -aac_is 1 parameter as it has always been. Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2015-08-21 20:13:26 +02:00
const float freq_mult = avctx->sample_rate/(1024.0f/sce0->ics.num_windows)/2.0f;
AAC encoder: improve SF range utilization This patch does 4 things, all of which interact and thus it woudln't be possible to commit them separately without causing either quality regressions or assertion failures. Fate comparison targets don't all reflect improvements in quality, yet listening tests show substantially improved quality and stability. 1. Increase SF range utilization. The spec requires SF delta values to be constrained within the range -60..60. The previous code was applying that range to the whole SF array and not only the deltas of consecutive values, because doing so requires smarter code: zeroing or otherwise skipping a band may invalidate lots of SF choices. This patch implements that logic to allow the coders to utilize the full dynamic range of scalefactors, increasing quality quite considerably, and fixing delta-SF-related assertion failures, since now the limitation is enforced rather than asserted. 2. PNS tweaks The previous modification makes big improvements in twoloop's efficiency, and every time that happens PNS logic needs to be tweaked accordingly to avoid it from stepping all over twoloop's decisions. This patch includes modifications of the sort. 3. Account for lowpass cutoff during PSY analysis The closer PSY's allocation is to final allocation the better the quality is, and given these modifications, twoloop is now very efficient at avoiding holes. Thus, to compute accurate thresholds, PSY needs to account for the lowpass applied implicitly during twoloop (by zeroing high bands). This patch makes twoloop set the cutoff in psymodel's context the first time it runs, and makes PSY account for it during threshold computation, making PE and threshold computations closer to the final allocation and thus achieving better subjective quality. 4. Tweaks to RC lambda tracking loop in relation to PNS Without this tweak some corner cases cause quality regressions. Basically, lambda needs to react faster to overall bitrate efficiency changes since now PNS can be quite successful in enforcing maximum bitrates, when PSY allocates too many bits to the lower bands, suppressing the signals RC logic uses to lower lambda in those cases and causing aggressive PNS. This tweak makes PNS much less aggressive, though it can still use some further tweaks. Also update MIPS specializations and adjust fuzz Also in lavc/mips/aacpsy_mips.h: remove trailing whitespace
2015-12-01 08:28:36 +02:00
uint8_t nextband1[128];
aaccoder: move the Intensity Stereo implementation out This commit moves the intensity stereo implementation out from aaccoder and into a separate file. This was possible using the previous commits. This commit also drastically improves the IS implementation by making it phase invariant e.g. it will always choose the best possible phase regardless of whether M/S coding is on or most of the coefficients have identical phases. This also increases the quality and reduces any distortions introduced by enablind intensity stereo. Users are encouraged to test it out using the -aac_is 1 parameter as it has always been. Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2015-08-21 20:13:26 +02:00
if (!cpe->common_window)
return;
AAC encoder: improve SF range utilization This patch does 4 things, all of which interact and thus it woudln't be possible to commit them separately without causing either quality regressions or assertion failures. Fate comparison targets don't all reflect improvements in quality, yet listening tests show substantially improved quality and stability. 1. Increase SF range utilization. The spec requires SF delta values to be constrained within the range -60..60. The previous code was applying that range to the whole SF array and not only the deltas of consecutive values, because doing so requires smarter code: zeroing or otherwise skipping a band may invalidate lots of SF choices. This patch implements that logic to allow the coders to utilize the full dynamic range of scalefactors, increasing quality quite considerably, and fixing delta-SF-related assertion failures, since now the limitation is enforced rather than asserted. 2. PNS tweaks The previous modification makes big improvements in twoloop's efficiency, and every time that happens PNS logic needs to be tweaked accordingly to avoid it from stepping all over twoloop's decisions. This patch includes modifications of the sort. 3. Account for lowpass cutoff during PSY analysis The closer PSY's allocation is to final allocation the better the quality is, and given these modifications, twoloop is now very efficient at avoiding holes. Thus, to compute accurate thresholds, PSY needs to account for the lowpass applied implicitly during twoloop (by zeroing high bands). This patch makes twoloop set the cutoff in psymodel's context the first time it runs, and makes PSY account for it during threshold computation, making PE and threshold computations closer to the final allocation and thus achieving better subjective quality. 4. Tweaks to RC lambda tracking loop in relation to PNS Without this tweak some corner cases cause quality regressions. Basically, lambda needs to react faster to overall bitrate efficiency changes since now PNS can be quite successful in enforcing maximum bitrates, when PSY allocates too many bits to the lower bands, suppressing the signals RC logic uses to lower lambda in those cases and causing aggressive PNS. This tweak makes PNS much less aggressive, though it can still use some further tweaks. Also update MIPS specializations and adjust fuzz Also in lavc/mips/aacpsy_mips.h: remove trailing whitespace
2015-12-01 08:28:36 +02:00
/** Scout out next nonzero bands */
ff_init_nextband_map(sce1, nextband1);
aaccoder: move the Intensity Stereo implementation out This commit moves the intensity stereo implementation out from aaccoder and into a separate file. This was possible using the previous commits. This commit also drastically improves the IS implementation by making it phase invariant e.g. it will always choose the best possible phase regardless of whether M/S coding is on or most of the coefficients have identical phases. This also increases the quality and reduces any distortions introduced by enablind intensity stereo. Users are encouraged to test it out using the -aac_is 1 parameter as it has always been. Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2015-08-21 20:13:26 +02:00
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++) {
if (start*freq_mult > INT_STEREO_LOW_LIMIT*(s->lambda/170.0f) &&
cpe->ch[0].band_type[w*16+g] != NOISE_BT && !cpe->ch[0].zeroes[w*16+g] &&
AAC encoder: improve SF range utilization This patch does 4 things, all of which interact and thus it woudln't be possible to commit them separately without causing either quality regressions or assertion failures. Fate comparison targets don't all reflect improvements in quality, yet listening tests show substantially improved quality and stability. 1. Increase SF range utilization. The spec requires SF delta values to be constrained within the range -60..60. The previous code was applying that range to the whole SF array and not only the deltas of consecutive values, because doing so requires smarter code: zeroing or otherwise skipping a band may invalidate lots of SF choices. This patch implements that logic to allow the coders to utilize the full dynamic range of scalefactors, increasing quality quite considerably, and fixing delta-SF-related assertion failures, since now the limitation is enforced rather than asserted. 2. PNS tweaks The previous modification makes big improvements in twoloop's efficiency, and every time that happens PNS logic needs to be tweaked accordingly to avoid it from stepping all over twoloop's decisions. This patch includes modifications of the sort. 3. Account for lowpass cutoff during PSY analysis The closer PSY's allocation is to final allocation the better the quality is, and given these modifications, twoloop is now very efficient at avoiding holes. Thus, to compute accurate thresholds, PSY needs to account for the lowpass applied implicitly during twoloop (by zeroing high bands). This patch makes twoloop set the cutoff in psymodel's context the first time it runs, and makes PSY account for it during threshold computation, making PE and threshold computations closer to the final allocation and thus achieving better subjective quality. 4. Tweaks to RC lambda tracking loop in relation to PNS Without this tweak some corner cases cause quality regressions. Basically, lambda needs to react faster to overall bitrate efficiency changes since now PNS can be quite successful in enforcing maximum bitrates, when PSY allocates too many bits to the lower bands, suppressing the signals RC logic uses to lower lambda in those cases and causing aggressive PNS. This tweak makes PNS much less aggressive, though it can still use some further tweaks. Also update MIPS specializations and adjust fuzz Also in lavc/mips/aacpsy_mips.h: remove trailing whitespace
2015-12-01 08:28:36 +02:00
cpe->ch[1].band_type[w*16+g] != NOISE_BT && !cpe->ch[1].zeroes[w*16+g] &&
ff_sfdelta_can_remove_band(sce1, nextband1, prev_sf1, w*16+g)) {
AAC encoder: Extensive improvements This finalizes merging of the work in the patches in ticket #2686. Improvements to twoloop and RC logic are extensive. The non-exhaustive list of twoloop improvments includes: - Tweaks to distortion limits on the RD optimization phase of twoloop - Deeper search in twoloop - PNS information marking to let twoloop decide when to use it (turned out having the decision made separately wasn't working) - Tonal band detection and priorization - Better band energy conservation rules - Strict hole avoidance For rate control: - Use psymodel's bit allocation to allow proper use of the bit reservoir. Don't work against the bit reservoir by moving lambda in the opposite direction when psymodel decides to allocate more/less bits to a frame. - Retry the encode if the effective rate lies outside a reasonable margin of psymodel's allocation or the selected ABR. - Log average lambda at the end. Useful info for everyone, but especially for tuning of the various encoder constants that relate to lambda feedback. Psy: - Do not apply lowpass with a FIR filter, instead just let the coder zero bands above the cutoff. The FIR filter induces group delay, and while zeroing bands causes ripple, it's lost in the quantization noise. - Experimental VBR bit allocation code - Tweak automatic lowpass filter threshold to maximize audio bandwidth at all bitrates while still providing acceptable, stable quality. I/S: - Phase decision fixes. Unrelated to #2686, but the bugs only surfaced when the merge was finalized. Measure I/S band energy accounting for phase, and prevent I/S and M/S from being applied both. PNS: - Avoid marking short bands with PNS when they're part of a window group in which there's a large variation of energy from one window to the next. PNS can't preserve those and the effect is extremely noticeable. M/S: - Implement BMLD protection similar to the specified in ISO-IEC/13818:7-2003, Appendix C Section 6.1. Since M/S decision doesn't conform to section 6.1, a different method had to be implemented, but should provide equivalent protection. - Move the decision logic closer to the method specified in ISO-IEC/13818:7-2003, Appendix C Section 6.1. Specifically, make sure M/S needs less bits than dual stereo. - Don't apply M/S in bands that are using I/S Now, this of course needed adjustments in the compare targets and fuzz factors of the AAC encoder's fate tests, but if wondering why the targets go up (more distortion), consider the previous coder was using too many bits on LF content (far more than required by psy), and thus those signals will now be more distorted, not less. The extra distortion isn't audible though, I carried extensive ABX testing to make sure. A very similar patch was also extensively tested by Kamendo2 in the context of #2686.
2015-10-11 22:29:50 +02:00
float ener0 = 0.0f, ener1 = 0.0f, ener01 = 0.0f, ener01p = 0.0f;
aacenc_is: rename variable 'erf' is far from the best name for a variable and is not very descriptive since the actual variable points to the comparitively best IS phase. Therefore rename it to 'best'. Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2015-12-21 19:23:38 +02:00
struct AACISError ph_err1, ph_err2, *best;
aaccoder: move the Intensity Stereo implementation out This commit moves the intensity stereo implementation out from aaccoder and into a separate file. This was possible using the previous commits. This commit also drastically improves the IS implementation by making it phase invariant e.g. it will always choose the best possible phase regardless of whether M/S coding is on or most of the coefficients have identical phases. This also increases the quality and reduces any distortions introduced by enablind intensity stereo. Users are encouraged to test it out using the -aac_is 1 parameter as it has always been. Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2015-08-21 20:13:26 +02:00
for (w2 = 0; w2 < sce0->ics.group_len[w]; w2++) {
for (i = 0; i < sce0->ics.swb_sizes[g]; i++) {
AAC encoder: use signed coeffs when measuring IS energy I/S energy, especially when it comes to phase cancellations, needs to use signed coefficients as input, yet it was using abs'd coefficients. That was a slight bug.
2016-01-17 01:47:00 +02:00
float coef0 = sce0->coeffs[start+(w+w2)*128+i];
float coef1 = sce1->coeffs[start+(w+w2)*128+i];
aacenc_is: add a flag to use pure coefficients instead This commit adds a flag to use the pure coefficients instead of the processed ones (sce->coeffs). This is needed because IS will apply the changes to the coefficients immediately before the adjust_common_prediction function and it doesn't make sense to measure stereo channel coefficient difference when one of the channels coefficients are all zero. Therefore add a flag to use pure coefficients in that case. TNS is the only thing touching the coefficients before IS so common window prediction will not take that into account but the effect of the TNS filter per coefficient can be small (a few percent) so to some approximation it's fine to just ignore that. Also fixed a small error which doesn't alter the results that much. pow(sqrt(number), 3.0/4.0) == pow(number, 3.0/8.0) != pow(number, 3.0/4.0). Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2015-09-05 09:32:09 +02:00
ener0 += coef0*coef0;
ener1 += coef1*coef1;
aaccoder: move the Intensity Stereo implementation out This commit moves the intensity stereo implementation out from aaccoder and into a separate file. This was possible using the previous commits. This commit also drastically improves the IS implementation by making it phase invariant e.g. it will always choose the best possible phase regardless of whether M/S coding is on or most of the coefficients have identical phases. This also increases the quality and reduces any distortions introduced by enablind intensity stereo. Users are encouraged to test it out using the -aac_is 1 parameter as it has always been. Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2015-08-21 20:13:26 +02:00
ener01 += (coef0 + coef1)*(coef0 + coef1);
AAC encoder: Extensive improvements This finalizes merging of the work in the patches in ticket #2686. Improvements to twoloop and RC logic are extensive. The non-exhaustive list of twoloop improvments includes: - Tweaks to distortion limits on the RD optimization phase of twoloop - Deeper search in twoloop - PNS information marking to let twoloop decide when to use it (turned out having the decision made separately wasn't working) - Tonal band detection and priorization - Better band energy conservation rules - Strict hole avoidance For rate control: - Use psymodel's bit allocation to allow proper use of the bit reservoir. Don't work against the bit reservoir by moving lambda in the opposite direction when psymodel decides to allocate more/less bits to a frame. - Retry the encode if the effective rate lies outside a reasonable margin of psymodel's allocation or the selected ABR. - Log average lambda at the end. Useful info for everyone, but especially for tuning of the various encoder constants that relate to lambda feedback. Psy: - Do not apply lowpass with a FIR filter, instead just let the coder zero bands above the cutoff. The FIR filter induces group delay, and while zeroing bands causes ripple, it's lost in the quantization noise. - Experimental VBR bit allocation code - Tweak automatic lowpass filter threshold to maximize audio bandwidth at all bitrates while still providing acceptable, stable quality. I/S: - Phase decision fixes. Unrelated to #2686, but the bugs only surfaced when the merge was finalized. Measure I/S band energy accounting for phase, and prevent I/S and M/S from being applied both. PNS: - Avoid marking short bands with PNS when they're part of a window group in which there's a large variation of energy from one window to the next. PNS can't preserve those and the effect is extremely noticeable. M/S: - Implement BMLD protection similar to the specified in ISO-IEC/13818:7-2003, Appendix C Section 6.1. Since M/S decision doesn't conform to section 6.1, a different method had to be implemented, but should provide equivalent protection. - Move the decision logic closer to the method specified in ISO-IEC/13818:7-2003, Appendix C Section 6.1. Specifically, make sure M/S needs less bits than dual stereo. - Don't apply M/S in bands that are using I/S Now, this of course needed adjustments in the compare targets and fuzz factors of the AAC encoder's fate tests, but if wondering why the targets go up (more distortion), consider the previous coder was using too many bits on LF content (far more than required by psy), and thus those signals will now be more distorted, not less. The extra distortion isn't audible though, I carried extensive ABX testing to make sure. A very similar patch was also extensively tested by Kamendo2 in the context of #2686.
2015-10-11 22:29:50 +02:00
ener01p += (coef0 - coef1)*(coef0 - coef1);
aaccoder: move the Intensity Stereo implementation out This commit moves the intensity stereo implementation out from aaccoder and into a separate file. This was possible using the previous commits. This commit also drastically improves the IS implementation by making it phase invariant e.g. it will always choose the best possible phase regardless of whether M/S coding is on or most of the coefficients have identical phases. This also increases the quality and reduces any distortions introduced by enablind intensity stereo. Users are encouraged to test it out using the -aac_is 1 parameter as it has always been. Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2015-08-21 20:13:26 +02:00
}
}
aacenc: Add missing ff_ prefixes Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com> Reviewed-by: Ganesh Ajjanagadde <gajjanag@mit.edu>
2015-08-22 07:11:23 +02:00
ph_err1 = ff_aac_is_encoding_err(s, cpe, start, w, g,
AAC encoder: Extensive improvements This finalizes merging of the work in the patches in ticket #2686. Improvements to twoloop and RC logic are extensive. The non-exhaustive list of twoloop improvments includes: - Tweaks to distortion limits on the RD optimization phase of twoloop - Deeper search in twoloop - PNS information marking to let twoloop decide when to use it (turned out having the decision made separately wasn't working) - Tonal band detection and priorization - Better band energy conservation rules - Strict hole avoidance For rate control: - Use psymodel's bit allocation to allow proper use of the bit reservoir. Don't work against the bit reservoir by moving lambda in the opposite direction when psymodel decides to allocate more/less bits to a frame. - Retry the encode if the effective rate lies outside a reasonable margin of psymodel's allocation or the selected ABR. - Log average lambda at the end. Useful info for everyone, but especially for tuning of the various encoder constants that relate to lambda feedback. Psy: - Do not apply lowpass with a FIR filter, instead just let the coder zero bands above the cutoff. The FIR filter induces group delay, and while zeroing bands causes ripple, it's lost in the quantization noise. - Experimental VBR bit allocation code - Tweak automatic lowpass filter threshold to maximize audio bandwidth at all bitrates while still providing acceptable, stable quality. I/S: - Phase decision fixes. Unrelated to #2686, but the bugs only surfaced when the merge was finalized. Measure I/S band energy accounting for phase, and prevent I/S and M/S from being applied both. PNS: - Avoid marking short bands with PNS when they're part of a window group in which there's a large variation of energy from one window to the next. PNS can't preserve those and the effect is extremely noticeable. M/S: - Implement BMLD protection similar to the specified in ISO-IEC/13818:7-2003, Appendix C Section 6.1. Since M/S decision doesn't conform to section 6.1, a different method had to be implemented, but should provide equivalent protection. - Move the decision logic closer to the method specified in ISO-IEC/13818:7-2003, Appendix C Section 6.1. Specifically, make sure M/S needs less bits than dual stereo. - Don't apply M/S in bands that are using I/S Now, this of course needed adjustments in the compare targets and fuzz factors of the AAC encoder's fate tests, but if wondering why the targets go up (more distortion), consider the previous coder was using too many bits on LF content (far more than required by psy), and thus those signals will now be more distorted, not less. The extra distortion isn't audible though, I carried extensive ABX testing to make sure. A very similar patch was also extensively tested by Kamendo2 in the context of #2686.
2015-10-11 22:29:50 +02:00
ener0, ener1, ener01p, 0, -1);
aacenc: Add missing ff_ prefixes Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com> Reviewed-by: Ganesh Ajjanagadde <gajjanag@mit.edu>
2015-08-22 07:11:23 +02:00
ph_err2 = ff_aac_is_encoding_err(s, cpe, start, w, g,
aacenc_is: add a flag to use pure coefficients instead This commit adds a flag to use the pure coefficients instead of the processed ones (sce->coeffs). This is needed because IS will apply the changes to the coefficients immediately before the adjust_common_prediction function and it doesn't make sense to measure stereo channel coefficient difference when one of the channels coefficients are all zero. Therefore add a flag to use pure coefficients in that case. TNS is the only thing touching the coefficients before IS so common window prediction will not take that into account but the effect of the TNS filter per coefficient can be small (a few percent) so to some approximation it's fine to just ignore that. Also fixed a small error which doesn't alter the results that much. pow(sqrt(number), 3.0/4.0) == pow(number, 3.0/8.0) != pow(number, 3.0/4.0). Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2015-09-05 09:32:09 +02:00
ener0, ener1, ener01, 0, +1);
aacenc_is: rename variable 'erf' is far from the best name for a variable and is not very descriptive since the actual variable points to the comparitively best IS phase. Therefore rename it to 'best'. Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2015-12-21 19:23:38 +02:00
best = (ph_err1.pass && ph_err1.error < ph_err2.error) ? &ph_err1 : &ph_err2;
if (best->pass) {
aaccoder: move the Intensity Stereo implementation out This commit moves the intensity stereo implementation out from aaccoder and into a separate file. This was possible using the previous commits. This commit also drastically improves the IS implementation by making it phase invariant e.g. it will always choose the best possible phase regardless of whether M/S coding is on or most of the coefficients have identical phases. This also increases the quality and reduces any distortions introduced by enablind intensity stereo. Users are encouraged to test it out using the -aac_is 1 parameter as it has always been. Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2015-08-21 20:13:26 +02:00
cpe->is_mask[w*16+g] = 1;
AAC encoder: Extensive improvements This finalizes merging of the work in the patches in ticket #2686. Improvements to twoloop and RC logic are extensive. The non-exhaustive list of twoloop improvments includes: - Tweaks to distortion limits on the RD optimization phase of twoloop - Deeper search in twoloop - PNS information marking to let twoloop decide when to use it (turned out having the decision made separately wasn't working) - Tonal band detection and priorization - Better band energy conservation rules - Strict hole avoidance For rate control: - Use psymodel's bit allocation to allow proper use of the bit reservoir. Don't work against the bit reservoir by moving lambda in the opposite direction when psymodel decides to allocate more/less bits to a frame. - Retry the encode if the effective rate lies outside a reasonable margin of psymodel's allocation or the selected ABR. - Log average lambda at the end. Useful info for everyone, but especially for tuning of the various encoder constants that relate to lambda feedback. Psy: - Do not apply lowpass with a FIR filter, instead just let the coder zero bands above the cutoff. The FIR filter induces group delay, and while zeroing bands causes ripple, it's lost in the quantization noise. - Experimental VBR bit allocation code - Tweak automatic lowpass filter threshold to maximize audio bandwidth at all bitrates while still providing acceptable, stable quality. I/S: - Phase decision fixes. Unrelated to #2686, but the bugs only surfaced when the merge was finalized. Measure I/S band energy accounting for phase, and prevent I/S and M/S from being applied both. PNS: - Avoid marking short bands with PNS when they're part of a window group in which there's a large variation of energy from one window to the next. PNS can't preserve those and the effect is extremely noticeable. M/S: - Implement BMLD protection similar to the specified in ISO-IEC/13818:7-2003, Appendix C Section 6.1. Since M/S decision doesn't conform to section 6.1, a different method had to be implemented, but should provide equivalent protection. - Move the decision logic closer to the method specified in ISO-IEC/13818:7-2003, Appendix C Section 6.1. Specifically, make sure M/S needs less bits than dual stereo. - Don't apply M/S in bands that are using I/S Now, this of course needed adjustments in the compare targets and fuzz factors of the AAC encoder's fate tests, but if wondering why the targets go up (more distortion), consider the previous coder was using too many bits on LF content (far more than required by psy), and thus those signals will now be more distorted, not less. The extra distortion isn't audible though, I carried extensive ABX testing to make sure. A very similar patch was also extensively tested by Kamendo2 in the context of #2686.
2015-10-11 22:29:50 +02:00
cpe->ms_mask[w*16+g] = 0;
aacenc_is: rename variable 'erf' is far from the best name for a variable and is not very descriptive since the actual variable points to the comparitively best IS phase. Therefore rename it to 'best'. Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2015-12-21 19:23:38 +02:00
cpe->ch[0].is_ener[w*16+g] = sqrt(ener0 / best->ener01);
aaccoder: move the Intensity Stereo implementation out This commit moves the intensity stereo implementation out from aaccoder and into a separate file. This was possible using the previous commits. This commit also drastically improves the IS implementation by making it phase invariant e.g. it will always choose the best possible phase regardless of whether M/S coding is on or most of the coefficients have identical phases. This also increases the quality and reduces any distortions introduced by enablind intensity stereo. Users are encouraged to test it out using the -aac_is 1 parameter as it has always been. Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2015-08-21 20:13:26 +02:00
cpe->ch[1].is_ener[w*16+g] = ener0/ener1;
aacenc_is: rename variable 'erf' is far from the best name for a variable and is not very descriptive since the actual variable points to the comparitively best IS phase. Therefore rename it to 'best'. Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2015-12-21 19:23:38 +02:00
cpe->ch[1].band_type[w*16+g] = (best->phase > 0) ? INTENSITY_BT : INTENSITY_BT2;
AAC encoder: encode out-of-phase I/S efficiently Use the ability to invert phase with ms_mask instead of changing the codebook when possible, to avoid having to switch codebooks if some bands are INTENSTY_BT and others are INTENSITY_BT2, since usually a set ms_mask uses less bits that a codebook change. While it may not always be a win (ie: if it causes an ms_mask bitmap to be sent when it wouldn't have been otherwise), it's unlikely since the ms_mask bitmap will almost always be there already for M/S itself.
2016-01-10 08:04:21 +02:00
if (prev_is && prev_bt != cpe->ch[1].band_type[w*16+g]) {
/** Flip M/S mask and pick the other CB, since it encodes more efficiently */
cpe->ms_mask[w*16+g] = 1;
cpe->ch[1].band_type[w*16+g] = (best->phase > 0) ? INTENSITY_BT2 : INTENSITY_BT;
}
prev_bt = cpe->ch[1].band_type[w*16+g];
aaccoder: move the Intensity Stereo implementation out This commit moves the intensity stereo implementation out from aaccoder and into a separate file. This was possible using the previous commits. This commit also drastically improves the IS implementation by making it phase invariant e.g. it will always choose the best possible phase regardless of whether M/S coding is on or most of the coefficients have identical phases. This also increases the quality and reduces any distortions introduced by enablind intensity stereo. Users are encouraged to test it out using the -aac_is 1 parameter as it has always been. Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2015-08-21 20:13:26 +02:00
count++;
}
}
AAC encoder: improve SF range utilization This patch does 4 things, all of which interact and thus it woudln't be possible to commit them separately without causing either quality regressions or assertion failures. Fate comparison targets don't all reflect improvements in quality, yet listening tests show substantially improved quality and stability. 1. Increase SF range utilization. The spec requires SF delta values to be constrained within the range -60..60. The previous code was applying that range to the whole SF array and not only the deltas of consecutive values, because doing so requires smarter code: zeroing or otherwise skipping a band may invalidate lots of SF choices. This patch implements that logic to allow the coders to utilize the full dynamic range of scalefactors, increasing quality quite considerably, and fixing delta-SF-related assertion failures, since now the limitation is enforced rather than asserted. 2. PNS tweaks The previous modification makes big improvements in twoloop's efficiency, and every time that happens PNS logic needs to be tweaked accordingly to avoid it from stepping all over twoloop's decisions. This patch includes modifications of the sort. 3. Account for lowpass cutoff during PSY analysis The closer PSY's allocation is to final allocation the better the quality is, and given these modifications, twoloop is now very efficient at avoiding holes. Thus, to compute accurate thresholds, PSY needs to account for the lowpass applied implicitly during twoloop (by zeroing high bands). This patch makes twoloop set the cutoff in psymodel's context the first time it runs, and makes PSY account for it during threshold computation, making PE and threshold computations closer to the final allocation and thus achieving better subjective quality. 4. Tweaks to RC lambda tracking loop in relation to PNS Without this tweak some corner cases cause quality regressions. Basically, lambda needs to react faster to overall bitrate efficiency changes since now PNS can be quite successful in enforcing maximum bitrates, when PSY allocates too many bits to the lower bands, suppressing the signals RC logic uses to lower lambda in those cases and causing aggressive PNS. This tweak makes PNS much less aggressive, though it can still use some further tweaks. Also update MIPS specializations and adjust fuzz Also in lavc/mips/aacpsy_mips.h: remove trailing whitespace
2015-12-01 08:28:36 +02:00
if (!sce1->zeroes[w*16+g] && sce1->band_type[w*16+g] < RESERVED_BT)
prev_sf1 = sce1->sf_idx[w*16+g];
AAC encoder: encode out-of-phase I/S efficiently Use the ability to invert phase with ms_mask instead of changing the codebook when possible, to avoid having to switch codebooks if some bands are INTENSTY_BT and others are INTENSITY_BT2, since usually a set ms_mask uses less bits that a codebook change. While it may not always be a win (ie: if it causes an ms_mask bitmap to be sent when it wouldn't have been otherwise), it's unlikely since the ms_mask bitmap will almost always be there already for M/S itself.
2016-01-10 08:04:21 +02:00
prev_is = cpe->is_mask[w*16+g];
aaccoder: move the Intensity Stereo implementation out This commit moves the intensity stereo implementation out from aaccoder and into a separate file. This was possible using the previous commits. This commit also drastically improves the IS implementation by making it phase invariant e.g. it will always choose the best possible phase regardless of whether M/S coding is on or most of the coefficients have identical phases. This also increases the quality and reduces any distortions introduced by enablind intensity stereo. Users are encouraged to test it out using the -aac_is 1 parameter as it has always been. Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2015-08-21 20:13:26 +02:00
start += sce0->ics.swb_sizes[g];
}
}
cpe->is_mode = !!count;
}
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