- 21 Oct, 2016 1 commit
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Andreas Cadhalpun authored
Thanks to Mathieu Malaterre <malat@debian.org> for reporting the Que/Queue typo. (https://bugs.debian.org/839542) Reviewed-by: Lou Logan <lou@lrcd.com> Signed-off-by: Andreas Cadhalpun <Andreas.Cadhalpun@googlemail.com>
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- 02 Dec, 2015 1 commit
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Claudio Freire authored
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
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- 11 Oct, 2015 1 commit
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Claudio Freire authored
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.
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- 23 Sep, 2015 1 commit
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Claudio Freire authored
This patch modifies the encode frame function to retry encoding the frame when the resulting bit count is too far off target, but only adjusting lambda in small, incremental step. It also makes the logic more conservative - otherwise it will contend with bit reservoir-related variations in bit allocation, and result in artifacts when frame have to be truncated (usually at high bit rates transitioning from low complexity to high complexity).
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- 27 Jul, 2015 1 commit
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Claudio Freire authored
Avoid clipping due to quantization noise to produce audible artifacts, by detecting near-clipping signals and both attenuating them a little and encoding escape-encoded bands (usually the loudest) rounding towards zero instead of nearest, which tends to decrease overall energy and thus clipping. Currently fate tests measure numerical error so this change makes tests using asynth (which are near clipping) report higher error not less, because of window attenuation. Yet, they sound better, not worse (albeit subtle, other samples aren't subtle at all). Only measuring psychoacoustically weighted error would make for a representative test, so that will be left for a future patch. Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
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- 28 Jun, 2015 1 commit
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Rostislav Pehlivanov authored
This commit adds the energy spread to the struct for each band and removes 2 unused fields. distortion and perceptual_weight were not referenced in any file nor were they set to any value, so it was safe to remove them. The energy spread is currently only used in the aac psy model. It's defined as being proportional to the tonality of each band. Reviewed-by: Claudio Freire <klaussfreire@gmail.com> Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
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- 25 May, 2014 1 commit
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Michael Niedermayer authored
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
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- 23 Feb, 2013 1 commit
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Diego Biurrun authored
The init functions marked as av_cold have to be executed in any case, so there is no gain from trying to mark paths leading to such functions as unlikely.
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- 29 Jul, 2012 1 commit
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Michael Niedermayer authored
Improves subjective quality Formula and testing by: kamedo2 <fujisakihir90@yahoo.co.jp> Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
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- 23 Jan, 2012 2 commits
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Nathan Caldwell authored
Signed-off-by: Alex Converse <alex.converse@gmail.com>
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Nathan Caldwell authored
Signed-off-by: Alex Converse <alex.converse@gmail.com>
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- 29 Jun, 2011 2 commits
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Nathan Caldwell authored
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Nathan Caldwell authored
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- 08 May, 2011 1 commit
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Nathan Caldwell authored
Instead use the function pointers directly.
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- 05 Apr, 2011 1 commit
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Nathan Caldwell authored
Signed-off-by: Janne Grunau <janne-libav@jannau.net>
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- 19 Mar, 2011 1 commit
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Mans Rullgard authored
Signed-off-by: Mans Rullgard <mans@mansr.com>
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- 30 Aug, 2010 1 commit
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Alex Converse authored
Originally committed as revision 24999 to svn://svn.ffmpeg.org/ffmpeg/trunk
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- 08 Jul, 2009 2 commits
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Alex Converse authored
Originally committed as revision 19376 to svn://svn.ffmpeg.org/ffmpeg/trunk
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Alex Converse authored
Originally committed as revision 19375 to svn://svn.ffmpeg.org/ffmpeg/trunk
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