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12 Commits

Author SHA1 Message Date
Andreas Rheinhardt
57d305207a avcodec/aacenc_quantization: Deduplicate quantization functions
Up until now, there were four copies of
quantize_and_encode_band_cost_(ZERO|[SU]QUAD|[SU]PAIR|ESC|NONE|NOISE|STEREO)
(namely in aaccoder.o, aacenc_is.o, aacenc_ltp.o, aacenc_pred.o).
As 43b378a0d3 says, this is meant to
enable more optimizations.

Yet neither GCC nor Clang performed such optimizations: The functions
in the aforementioned files are not optimized according to
the specifics of the calls in the respective file. Therefore
duplicating them is a waste of space; this commit therefore stops doing
so. The remaining copy is placed into aaccoder.c (which is the only
place where the "round to zero" variant of quantize_and_encode_band()
is used, so that this can be completely internal to aaccoder.c).

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2022-08-05 03:28:45 +02:00
Andreas Rheinhardt
386990a955 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>
2022-08-05 03:28:45 +02:00
Rostislav Pehlivanov
d2ae5f77c6 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>
2016-10-18 21:41:18 +01:00
Rostislav Pehlivanov
02172d93f6 Revert "aacenc: use av_clip() instead of av_clip() during quantization"
This reverts commit c0918613a0, since it
triggered a new assertion with gcc.
This bug definitely needs a true proper fix.
2016-03-30 02:31:22 +01:00
Rostislav Pehlivanov
c0918613a0 aacenc: use av_clip() instead of av_clip() during quantization
Seems like clang might be miscompiling it and causing a signed integer overflow,
making a FATE test fail.
Doesn't seem to affect performance, it only runs on the ESC codebook.

Reviewed-by: Claudio Freire <klaussfreire@gmail.com>
Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2016-03-30 01:04:43 +01:00
Rostislav Pehlivanov
e679a1e65f aacenc_quantization: fix header description
Two guesses as to which file was used as boilerplate.
2015-10-12 15:41:50 +01:00
Claudio Freire
b629c67ddf AAC encoder: memoize quantize_band_cost
The bulk of calls to quantize_band_cost are replaced
by a call to a version that memoizes, greatly improving
performance, since during coefficient search there is
a great deal of repeat work.

Memoization cannot always be applied, so do this in a
different function, and leave the original as-is.
2015-10-12 03:56:22 -03:00
Claudio Freire
01ecb7172b AAC encoder: Extensive improvements
This finalizes merging of the work in the patches in ticket .

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 , 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 .
2015-10-11 17:29:50 -03:00
Claudio Freire
8df9bf8e39 AAC encoder: refactor to resynchronize MIPS port
This patch refactors the AAC coders to reuse code
between the MIPS port and the regular, portable C code.
There were two main functions that had to use
hand-optimized versions of quantization code:
 - search_for_quantizers_twoloop
 - codebook_trellis_rate

Those two were split into their own template header
files so they can be inlined inside both the MIPS port
and the generic code. In each context, they'll link
to their specialized implementations, and thus be
optimized by the compiler.

This approach I believe is better than maintaining
several copies of each function. As past experience has
proven, having to keep those in sync was error prone.
In this way, they will remain in sync by default.

Also, an implementation of the dequantized output
argument for the optimized quantize_and_encode
functions is included in the patch. While the current
implementation of search_for_pred still isn't using
it, future iterations of main prediction probably will.
It should not imply any measurable performance hit while
not being used.
2015-09-16 23:14:26 -03:00
Rostislav Pehlivanov
7adb6d5aab aacenc_quantization: replace copysign() with a ternary operator
This commit removes the last thing a Windows environment can
complain about the AAC encoder code. Leftover from an old revision.

Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2015-08-22 08:50:41 +01:00
Timothy Gu
d4401a9e0d aacenc: Harmonize multiple inclusion guards
Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
Reviewed-by: Ganesh Ajjanagadde <gajjanag@mit.edu>
2015-08-22 04:56:36 +01:00
Rostislav Pehlivanov
43b378a0d3 aaccoder: move the quantization functions to a separate file
This commit moves the quantizer to a separate header file.
This allows the quantizer to be used from a separate files outside
of aaccoder without having to put another function pointer and will
result in a slight speedup as the compiler can do more optimizations.

This is required for commits following.

Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2015-08-21 18:53:14 +01:00