mirror of
https://github.com/FFmpeg/FFmpeg.git
synced 2024-11-21 10:55:51 +02:00
0b9a69f244
* qatar/master: (22 commits) aacdec: Fix PS in ADTS. avconv: Consistently use PIX_FMT_NONE. dsputil: use cpuflags in x86 emu_edge_core dsputil: use movups instead of movdqu in ff_emu_edge_core_sse() wma: initialize prev_block_len_bits, next_block_len_bits, and block_len_bits. mov: Remove some redundant and obsolete comments. Add libavutil/mathematics.h #includes for INFINITY doxy: structure libavformat groups doxy: introduce an empty structure in libavcodec doxy: provide a start page and document libavutil doxy: cleanup pixfmt.h regtest: split video encode/decode tests into individual targets ARM: add explicit .arch and .fpu directives to asm.S pthread: do not touch has_b_frames avconv: cleanup the transcoding loop in output_packet(). avconv: split subtitle transcoding out of output_packet(). avconv: split video transcoding out of output_packet(). avconv: split audio transcoding out of output_packet(). avconv: reindent. avconv: move streamcopy-only code out of decoding loop. ... Conflicts: avconv.c libavcodec/aaccoder.c libavcodec/pthread.c libavcodec/version.h libavutil/audioconvert.h libavutil/avutil.h libavutil/mem.h tests/ref/vsynth1/dv tests/ref/vsynth1/mpeg2thread tests/ref/vsynth2/dv tests/ref/vsynth2/mpeg2thread Merged-by: Michael Niedermayer <michaelni@gmx.at>
145 lines
3.7 KiB
C
145 lines
3.7 KiB
C
/*
|
|
* rational numbers
|
|
* Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
|
|
*
|
|
* 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
|
|
* rational numbers
|
|
* @author Michael Niedermayer <michaelni@gmx.at>
|
|
*/
|
|
|
|
#ifndef AVUTIL_RATIONAL_H
|
|
#define AVUTIL_RATIONAL_H
|
|
|
|
#include <stdint.h>
|
|
#include <limits.h>
|
|
#include "attributes.h"
|
|
|
|
/**
|
|
* @addtogroup lavu_math
|
|
* @{
|
|
*/
|
|
|
|
/**
|
|
* rational number numerator/denominator
|
|
*/
|
|
typedef struct AVRational{
|
|
int num; ///< numerator
|
|
int den; ///< denominator
|
|
} AVRational;
|
|
|
|
/**
|
|
* Compare two rationals.
|
|
* @param a first rational
|
|
* @param b second rational
|
|
* @return 0 if a==b, 1 if a>b, -1 if a<b, and INT_MIN if one of the
|
|
* values is of the form 0/0
|
|
*/
|
|
static inline int av_cmp_q(AVRational a, AVRational b){
|
|
const int64_t tmp= a.num * (int64_t)b.den - b.num * (int64_t)a.den;
|
|
|
|
if(tmp) return ((tmp ^ a.den ^ b.den)>>63)|1;
|
|
else if(b.den && a.den) return 0;
|
|
else if(a.num && b.num) return (a.num>>31) - (b.num>>31);
|
|
else return INT_MIN;
|
|
}
|
|
|
|
/**
|
|
* Convert rational to double.
|
|
* @param a rational to convert
|
|
* @return (double) a
|
|
*/
|
|
static inline double av_q2d(AVRational a){
|
|
return a.num / (double) a.den;
|
|
}
|
|
|
|
/**
|
|
* Reduce a fraction.
|
|
* This is useful for framerate calculations.
|
|
* @param dst_num destination numerator
|
|
* @param dst_den destination denominator
|
|
* @param num source numerator
|
|
* @param den source denominator
|
|
* @param max the maximum allowed for dst_num & dst_den
|
|
* @return 1 if exact, 0 otherwise
|
|
*/
|
|
int av_reduce(int *dst_num, int *dst_den, int64_t num, int64_t den, int64_t max);
|
|
|
|
/**
|
|
* Multiply two rationals.
|
|
* @param b first rational
|
|
* @param c second rational
|
|
* @return b*c
|
|
*/
|
|
AVRational av_mul_q(AVRational b, AVRational c) av_const;
|
|
|
|
/**
|
|
* Divide one rational by another.
|
|
* @param b first rational
|
|
* @param c second rational
|
|
* @return b/c
|
|
*/
|
|
AVRational av_div_q(AVRational b, AVRational c) av_const;
|
|
|
|
/**
|
|
* Add two rationals.
|
|
* @param b first rational
|
|
* @param c second rational
|
|
* @return b+c
|
|
*/
|
|
AVRational av_add_q(AVRational b, AVRational c) av_const;
|
|
|
|
/**
|
|
* Subtract one rational from another.
|
|
* @param b first rational
|
|
* @param c second rational
|
|
* @return b-c
|
|
*/
|
|
AVRational av_sub_q(AVRational b, AVRational c) av_const;
|
|
|
|
/**
|
|
* Convert a double precision floating point number to a rational.
|
|
* inf is expressed as {1,0} or {-1,0} depending on the sign.
|
|
*
|
|
* @param d double to convert
|
|
* @param max the maximum allowed numerator and denominator
|
|
* @return (AVRational) d
|
|
*/
|
|
AVRational av_d2q(double d, int max) av_const;
|
|
|
|
/**
|
|
* @return 1 if q1 is nearer to q than q2, -1 if q2 is nearer
|
|
* than q1, 0 if they have the same distance.
|
|
*/
|
|
int av_nearer_q(AVRational q, AVRational q1, AVRational q2);
|
|
|
|
/**
|
|
* Find the nearest value in q_list to q.
|
|
* @param q_list an array of rationals terminated by {0, 0}
|
|
* @return the index of the nearest value found in the array
|
|
*/
|
|
int av_find_nearest_q_idx(AVRational q, const AVRational* q_list);
|
|
|
|
/**
|
|
* @}
|
|
*/
|
|
|
|
#endif /* AVUTIL_RATIONAL_H */
|