From 43a97878ce14b72f0981164f87f2e35e14151312 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 11:22:09 +0200 Subject: Adding upstream version 110.0.1. Signed-off-by: Daniel Baumann --- media/ffvpx/libavutil/ffmath.h | 67 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 67 insertions(+) create mode 100644 media/ffvpx/libavutil/ffmath.h (limited to 'media/ffvpx/libavutil/ffmath.h') diff --git a/media/ffvpx/libavutil/ffmath.h b/media/ffvpx/libavutil/ffmath.h new file mode 100644 index 0000000000..aad1347f26 --- /dev/null +++ b/media/ffvpx/libavutil/ffmath.h @@ -0,0 +1,67 @@ +/* + * copyright (c) 2016 Ganesh Ajjanagadde + * + * 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 + * internal math functions header + */ + +#ifndef AVUTIL_FFMATH_H +#define AVUTIL_FFMATH_H + +#include "attributes.h" +#include "libm.h" + +/** + * Compute 10^x for floating point values. Note: this function is by no means + * "correctly rounded", and is meant as a fast, reasonably accurate approximation. + * For instance, maximum relative error for the double precision variant is + * ~ 1e-13 for very small and very large values. + * This is ~2x faster than GNU libm's approach, which is still off by 2ulp on + * some inputs. + * @param x exponent + * @return 10^x + */ +static av_always_inline double ff_exp10(double x) +{ + return exp2(M_LOG2_10 * x); +} + +static av_always_inline float ff_exp10f(float x) +{ + return exp2f(M_LOG2_10 * x); +} + +/** + * Compute x^y for floating point x, y. Note: this function is faster than the + * libm variant due to mainly 2 reasons: + * 1. It does not handle any edge cases. In particular, this is only guaranteed + * to work correctly for x > 0. + * 2. It is not as accurate as a standard nearly "correctly rounded" libm variant. + * @param x base + * @param y exponent + * @return x^y + */ +static av_always_inline float ff_fast_powf(float x, float y) +{ + return expf(logf(x) * y); +} + +#endif /* AVUTIL_FFMATH_H */ -- cgit v1.2.3