ffmpeg/libavutil/common.h

411 lines
10 KiB
C

/*
* copyright (c) 2006 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 common.h
* common internal and external API header
*/
#ifndef AVUTIL_COMMON_H
#define AVUTIL_COMMON_H
#include <inttypes.h>
#ifdef HAVE_AV_CONFIG_H
/* only include the following when compiling package */
# include "config.h"
# include <stdlib.h>
# include <stdio.h>
# include <string.h>
# include <ctype.h>
# include <limits.h>
# include <errno.h>
# include <math.h>
#endif /* HAVE_AV_CONFIG_H */
#define AV_GCC_VERSION_AT_LEAST(x,y) (defined(__GNUC__) && (__GNUC__ > x || __GNUC__ == x && __GNUC_MINOR__ >= y))
#ifndef av_always_inline
#if AV_GCC_VERSION_AT_LEAST(3,1)
# define av_always_inline __attribute__((always_inline)) inline
#else
# define av_always_inline inline
#endif
#endif
#ifndef av_noinline
#if AV_GCC_VERSION_AT_LEAST(3,1)
# define av_noinline __attribute__((noinline))
#else
# define av_noinline
#endif
#endif
#ifndef av_pure
#if AV_GCC_VERSION_AT_LEAST(3,1)
# define av_pure __attribute__((pure))
#else
# define av_pure
#endif
#endif
#ifndef av_const
#if AV_GCC_VERSION_AT_LEAST(2,6)
# define av_const __attribute__((const))
#else
# define av_const
#endif
#endif
#ifndef av_cold
#if (!defined(__ICC) || __ICC > 1100) && AV_GCC_VERSION_AT_LEAST(4,3)
# define av_cold __attribute__((cold))
#else
# define av_cold
#endif
#endif
#ifdef HAVE_AV_CONFIG_H
# include "internal.h"
#endif /* HAVE_AV_CONFIG_H */
#ifndef attribute_deprecated
#if AV_GCC_VERSION_AT_LEAST(3,1)
# define attribute_deprecated __attribute__((deprecated))
#else
# define attribute_deprecated
#endif
#endif
#ifndef av_unused
#if defined(__GNUC__)
# define av_unused __attribute__((unused))
#else
# define av_unused
#endif
#endif
#include "mem.h"
//rounded divison & shift
#define RSHIFT(a,b) ((a) > 0 ? ((a) + ((1<<(b))>>1))>>(b) : ((a) + ((1<<(b))>>1)-1)>>(b))
/* assume b>0 */
#define ROUNDED_DIV(a,b) (((a)>0 ? (a) + ((b)>>1) : (a) - ((b)>>1))/(b))
#define FFABS(a) ((a) >= 0 ? (a) : (-(a)))
#define FFSIGN(a) ((a) > 0 ? 1 : -1)
#define FFMAX(a,b) ((a) > (b) ? (a) : (b))
#define FFMAX3(a,b,c) FFMAX(FFMAX(a,b),c)
#define FFMIN(a,b) ((a) > (b) ? (b) : (a))
#define FFMIN3(a,b,c) FFMIN(FFMIN(a,b),c)
#define FFSWAP(type,a,b) do{type SWAP_tmp= b; b= a; a= SWAP_tmp;}while(0)
#define FF_ARRAY_ELEMS(a) (sizeof(a) / sizeof((a)[0]))
/* misc math functions */
extern const uint8_t ff_log2_tab[256];
static inline av_const int av_log2(unsigned int v)
{
int n = 0;
if (v & 0xffff0000) {
v >>= 16;
n += 16;
}
if (v & 0xff00) {
v >>= 8;
n += 8;
}
n += ff_log2_tab[v];
return n;
}
static inline av_const int av_log2_16bit(unsigned int v)
{
int n = 0;
if (v & 0xff00) {
v >>= 8;
n += 8;
}
n += ff_log2_tab[v];
return n;
}
/* median of 3 */
static inline av_const int mid_pred(int a, int b, int c)
{
#ifdef HAVE_CMOV
int i=b;
__asm__ volatile(
"cmp %2, %1 \n\t"
"cmovg %1, %0 \n\t"
"cmovg %2, %1 \n\t"
"cmp %3, %1 \n\t"
"cmovl %3, %1 \n\t"
"cmp %1, %0 \n\t"
"cmovg %1, %0 \n\t"
:"+&r"(i), "+&r"(a)
:"r"(b), "r"(c)
);
return i;
#elif 0
int t= (a-b)&((a-b)>>31);
a-=t;
b+=t;
b-= (b-c)&((b-c)>>31);
b+= (a-b)&((a-b)>>31);
return b;
#else
if(a>b){
if(c>b){
if(c>a) b=a;
else b=c;
}
}else{
if(b>c){
if(c>a) b=c;
else b=a;
}
}
return b;
#endif
}
/**
* clip a signed integer value into the amin-amax range
* @param a value to clip
* @param amin minimum value of the clip range
* @param amax maximum value of the clip range
* @return clipped value
*/
static inline av_const int av_clip(int a, int amin, int amax)
{
if (a < amin) return amin;
else if (a > amax) return amax;
else return a;
}
/**
* clip a signed integer value into the 0-255 range
* @param a value to clip
* @return clipped value
*/
static inline av_const uint8_t av_clip_uint8(int a)
{
if (a&(~255)) return (-a)>>31;
else return a;
}
/**
* clip a signed integer value into the -32768,32767 range
* @param a value to clip
* @return clipped value
*/
static inline av_const int16_t av_clip_int16(int a)
{
if ((a+32768) & ~65535) return (a>>31) ^ 32767;
else return a;
}
/**
* clip a float value into the amin-amax range
* @param a value to clip
* @param amin minimum value of the clip range
* @param amax maximum value of the clip range
* @return clipped value
*/
static inline av_const float av_clipf(float a, float amin, float amax)
{
if (a < amin) return amin;
else if (a > amax) return amax;
else return a;
}
/* math */
int64_t av_const ff_gcd(int64_t a, int64_t b);
/**
* converts fourcc string to int
*/
static inline av_pure int ff_get_fourcc(const char *s){
#ifdef HAVE_AV_CONFIG_H
assert( strlen(s)==4 );
#endif
return (s[0]) + (s[1]<<8) + (s[2]<<16) + (s[3]<<24);
}
#define MKTAG(a,b,c,d) (a | (b << 8) | (c << 16) | (d << 24))
#define MKBETAG(a,b,c,d) (d | (c << 8) | (b << 16) | (a << 24))
/*!
* \def GET_UTF8(val, GET_BYTE, ERROR)
* converts a UTF-8 character (up to 4 bytes long) to its 32-bit UCS-4 encoded form
* \param val is the output and should be of type uint32_t. It holds the converted
* UCS-4 character and should be a left value.
* \param GET_BYTE gets UTF-8 encoded bytes from any proper source. It can be
* a function or a statement whose return value or evaluated value is of type
* uint8_t. It will be executed up to 4 times for values in the valid UTF-8 range,
* and up to 7 times in the general case.
* \param ERROR action that should be taken when an invalid UTF-8 byte is returned
* from GET_BYTE. It should be a statement that jumps out of the macro,
* like exit(), goto, return, break, or continue.
*/
#define GET_UTF8(val, GET_BYTE, ERROR)\
val= GET_BYTE;\
{\
int ones= 7 - av_log2(val ^ 255);\
if(ones==1)\
ERROR\
val&= 127>>ones;\
while(--ones > 0){\
int tmp= GET_BYTE - 128;\
if(tmp>>6)\
ERROR\
val= (val<<6) + tmp;\
}\
}
/*!
* \def PUT_UTF8(val, tmp, PUT_BYTE)
* converts a 32-bit unicode character to its UTF-8 encoded form (up to 4 bytes long).
* \param val is an input only argument and should be of type uint32_t. It holds
* a ucs4 encoded unicode character that is to be converted to UTF-8. If
* val is given as a function it's executed only once.
* \param tmp is a temporary variable and should be of type uint8_t. It
* represents an intermediate value during conversion that is to be
* outputted by PUT_BYTE.
* \param PUT_BYTE writes the converted UTF-8 bytes to any proper destination.
* It could be a function or a statement, and uses tmp as the input byte.
* For example, PUT_BYTE could be "*output++ = tmp;" PUT_BYTE will be
* executed up to 4 times for values in the valid UTF-8 range and up to
* 7 times in the general case, depending on the length of the converted
* unicode character.
*/
#define PUT_UTF8(val, tmp, PUT_BYTE)\
{\
int bytes, shift;\
uint32_t in = val;\
if (in < 0x80) {\
tmp = in;\
PUT_BYTE\
} else {\
bytes = (av_log2(in) + 4) / 5;\
shift = (bytes - 1) * 6;\
tmp = (256 - (256 >> bytes)) | (in >> shift);\
PUT_BYTE\
while (shift >= 6) {\
shift -= 6;\
tmp = 0x80 | ((in >> shift) & 0x3f);\
PUT_BYTE\
}\
}\
}
#if defined(ARCH_X86) || defined(ARCH_PPC) || defined(ARCH_BFIN)
#define AV_READ_TIME read_time
#if defined(ARCH_X86)
static inline uint64_t read_time(void)
{
uint32_t a, d;
__asm__ volatile("rdtsc\n\t"
: "=a" (a), "=d" (d));
return ((uint64_t)d << 32) + a;
}
#elif ARCH_BFIN
static inline uint64_t read_time(void)
{
union {
struct {
unsigned lo;
unsigned hi;
} p;
unsigned long long c;
} t;
__asm__ volatile ("%0=cycles; %1=cycles2;" : "=d" (t.p.lo), "=d" (t.p.hi));
return t.c;
}
#else //FIXME check ppc64
static inline uint64_t read_time(void)
{
uint32_t tbu, tbl, temp;
/* from section 2.2.1 of the 32-bit PowerPC PEM */
__asm__ volatile(
"1:\n"
"mftbu %2\n"
"mftb %0\n"
"mftbu %1\n"
"cmpw %2,%1\n"
"bne 1b\n"
: "=r"(tbl), "=r"(tbu), "=r"(temp)
:
: "cc");
return (((uint64_t)tbu)<<32) | (uint64_t)tbl;
}
#endif
#elif defined(HAVE_GETHRTIME)
#define AV_READ_TIME gethrtime
#endif
#ifdef AV_READ_TIME
#define START_TIMER \
uint64_t tend;\
uint64_t tstart= AV_READ_TIME();\
#define STOP_TIMER(id) \
tend= AV_READ_TIME();\
{\
static uint64_t tsum=0;\
static int tcount=0;\
static int tskip_count=0;\
if(tcount<2 || tend - tstart < FFMAX(8*tsum/tcount, 2000)){\
tsum+= tend - tstart;\
tcount++;\
}else\
tskip_count++;\
if(((tcount+tskip_count)&(tcount+tskip_count-1))==0){\
av_log(NULL, AV_LOG_ERROR, "%"PRIu64" dezicycles in %s, %d runs, %d skips\n",\
tsum*10/tcount, id, tcount, tskip_count);\
}\
}
#else
#define START_TIMER
#define STOP_TIMER(id) {}
#endif
/**
* Returns NULL if CONFIG_SMALL is defined otherwise the argument
* without modifications, used to disable the definition of strings
* (for example AVCodec long_names).
*/
#ifdef CONFIG_SMALL
# define NULL_IF_CONFIG_SMALL(x) NULL
#else
# define NULL_IF_CONFIG_SMALL(x) x
#endif
#endif /* AVUTIL_COMMON_H */