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Macros | Functions
common.h File Reference

common internal and external API header More...

#include <errno.h>
#include <inttypes.h>
#include <limits.h>
#include <math.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "attributes.h"
#include "version.h"
#include "libavutil/avconfig.h"
#include "common.h"
#include "mem.h"

Go to the source code of this file.

Macros

#define AV_NE(be, le)   (le)
 
#define RSHIFT(a, b)   ((a) > 0 ? ((a) + ((1<<(b))>>1))>>(b) : ((a) + ((1<<(b))>>1)-1)>>(b))
 
#define ROUNDED_DIV(a, b)   (((a)>0 ? (a) + ((b)>>1) : (a) - ((b)>>1))/(b))
 
#define FF_CEIL_RSHIFT(a, b)
 
#define FFUDIV(a, b)   (((a)>0 ?(a):(a)-(b)+1) / (b))
 
#define FFUMOD(a, b)   ((a)-(b)*FFUDIV(a,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]))
 
#define FFALIGN(x, a)   (((x)+(a)-1)&~((a)-1))
 
#define MKTAG(a, b, c, d)   ((a) | ((b) << 8) | ((c) << 16) | ((unsigned)(d) << 24))
 
#define MKBETAG(a, b, c, d)   ((d) | ((c) << 8) | ((b) << 16) | ((unsigned)(a) << 24))
 
#define GET_UTF8(val, GET_BYTE, ERROR)
 Convert a UTF-8 character (up to 4 bytes) to its 32-bit UCS-4 encoded form. More...
 
#define GET_UTF16(val, GET_16BIT, ERROR)
 Convert a UTF-16 character (2 or 4 bytes) to its 32-bit UCS-4 encoded form. More...
 
#define PUT_UTF8(val, tmp, PUT_BYTE)
 Convert a 32-bit Unicode character to its UTF-8 encoded form (up to 4 bytes long). More...
 
#define PUT_UTF16(val, tmp, PUT_16BIT)
 Convert a 32-bit Unicode character to its UTF-16 encoded form (2 or 4 bytes). More...
 

Functions

av_const int av_log2 (unsigned v)
 Reverse the order of the bits of an 8-bits unsigned integer. More...
 
av_const int av_log2_16bit (unsigned v)
 
static av_always_inline
av_const int 
av_clip_c (int a, int amin, int amax)
 Clip a signed integer value into the amin-amax range. More...
 
static av_always_inline
av_const int64_t 
av_clip64_c (int64_t a, int64_t amin, int64_t amax)
 Clip a signed 64bit integer value into the amin-amax range. More...
 
static av_always_inline
av_const uint8_t 
av_clip_uint8_c (int a)
 Clip a signed integer value into the 0-255 range. More...
 
static av_always_inline
av_const int8_t 
av_clip_int8_c (int a)
 Clip a signed integer value into the -128,127 range. More...
 
static av_always_inline
av_const uint16_t 
av_clip_uint16_c (int a)
 Clip a signed integer value into the 0-65535 range. More...
 
static av_always_inline
av_const int16_t 
av_clip_int16_c (int a)
 Clip a signed integer value into the -32768,32767 range. More...
 
static av_always_inline
av_const int32_t 
av_clipl_int32_c (int64_t a)
 Clip a signed 64-bit integer value into the -2147483648,2147483647 range. More...
 
static av_always_inline
av_const unsigned 
av_clip_uintp2_c (int a, int p)
 Clip a signed integer to an unsigned power of two range. More...
 
static av_always_inline int av_sat_add32_c (int a, int b)
 Add two signed 32-bit values with saturation. More...
 
static av_always_inline int av_sat_dadd32_c (int a, int b)
 Add a doubled value to another value with saturation at both stages. More...
 
static av_always_inline
av_const float 
av_clipf_c (float a, float amin, float amax)
 Clip a float value into the amin-amax range. More...
 
static av_always_inline
av_const double 
av_clipd_c (double a, double amin, double amax)
 Clip a double value into the amin-amax range. More...
 
static av_always_inline
av_const int 
av_ceil_log2_c (int x)
 Compute ceil(log2(x)). More...
 
static av_always_inline
av_const int 
av_popcount_c (uint32_t x)
 Count number of bits set to one in x. More...
 
static av_always_inline
av_const int 
av_popcount64_c (uint64_t x)
 Count number of bits set to one in x. More...
 

Detailed Description

common internal and external API header

Definition in file common.h.

Macro Definition Documentation

#define AV_NE (   be,
  le 
)    (le)
Examples:
demuxing_decoding.c, and resampling_audio.c.

Definition at line 49 of file common.h.

Referenced by get_format_from_sample_fmt().

#define RSHIFT (   a,
 
)    ((a) > 0 ? ((a) + ((1<<(b))>>1))>>(b) : ((a) + ((1<<(b))>>1)-1)>>(b))

Definition at line 53 of file common.h.

#define ROUNDED_DIV (   a,
 
)    (((a)>0 ? (a) + ((b)>>1) : (a) - ((b)>>1))/(b))

Definition at line 55 of file common.h.

#define FF_CEIL_RSHIFT (   a,
 
)
Value:
(!av_builtin_constant_p(b) ? -((-(a)) >> (b)) \
: ((a) + (1<<(b)) - 1) >> (b))
#define av_builtin_constant_p
Definition: attributes.h:147

Definition at line 57 of file common.h.

#define FFUDIV (   a,
 
)    (((a)>0 ?(a):(a)-(b)+1) / (b))

Definition at line 59 of file common.h.

#define FFUMOD (   a,
 
)    ((a)-(b)*FFUDIV(a,b))

Definition at line 60 of file common.h.

#define FFABS (   a)    ((a) >= 0 ? (a) : (-(a)))

Definition at line 61 of file common.h.

#define FFSIGN (   a)    ((a) > 0 ? 1 : -1)

Definition at line 62 of file common.h.

#define FFMAX (   a,
 
)    ((a) > (b) ? (a) : (b))
Examples:
decoding_encoding.c.

Definition at line 64 of file common.h.

Referenced by select_sample_rate().

#define FFMAX3 (   a,
  b,
 
)    FFMAX(FFMAX(a,b),c)

Definition at line 65 of file common.h.

#define FFMIN (   a,
 
)    ((a) > (b) ? (b) : (a))
Examples:
avio_reading.c, demuxing_decoding.c, and transcode_aac.c.

Definition at line 66 of file common.h.

Referenced by decode_packet(), load_encode_and_write(), and read_packet().

#define FFMIN3 (   a,
  b,
 
)    FFMIN(FFMIN(a,b),c)

Definition at line 67 of file common.h.

#define FFSWAP (   type,
  a,
 
)    do{type SWAP_tmp= b; b= a; a= SWAP_tmp;}while(0)

Definition at line 69 of file common.h.

#define FF_ARRAY_ELEMS (   a)    (sizeof(a) / sizeof((a)[0]))
Examples:
demuxing_decoding.c, and resampling_audio.c.

Definition at line 70 of file common.h.

Referenced by get_format_from_sample_fmt().

#define FFALIGN (   x,
 
)    (((x)+(a)-1)&~((a)-1))

Definition at line 71 of file common.h.

#define MKTAG (   a,
  b,
  c,
 
)    ((a) | ((b) << 8) | ((c) << 16) | ((unsigned)(d) << 24))

Definition at line 290 of file common.h.

#define MKBETAG (   a,
  b,
  c,
 
)    ((d) | ((c) << 8) | ((b) << 16) | ((unsigned)(a) << 24))

Definition at line 291 of file common.h.

#define GET_UTF8 (   val,
  GET_BYTE,
  ERROR 
)
Value:
val= GET_BYTE;\
{\
uint32_t top = (val & 128) >> 1;\
if ((val & 0xc0) == 0x80 || val >= 0xFE)\
ERROR\
while (val & top) {\
int tmp= GET_BYTE - 128;\
if(tmp>>6)\
ERROR\
val= (val<<6) + tmp;\
top <<= 5;\
}\
val &= (top << 1) - 1;\
}

Convert a UTF-8 character (up to 4 bytes) to its 32-bit UCS-4 encoded form.

Parameters
valOutput value, must be an lvalue of type uint32_t.
GET_BYTEExpression reading one byte from the input. Evaluated up to 7 times (4 for the currently assigned Unicode range). With a memory buffer input, this could be *ptr++.
ERRORExpression to be evaluated on invalid input, typically a goto statement.
Warning
ERROR should not contain a loop control statement which could interact with the internal while loop, and should force an exit from the macro code (e.g. through a goto or a return) in order to prevent undefined results.

Definition at line 309 of file common.h.

#define GET_UTF16 (   val,
  GET_16BIT,
  ERROR 
)
Value:
val = GET_16BIT;\
{\
unsigned int hi = val - 0xD800;\
if (hi < 0x800) {\
val = GET_16BIT - 0xDC00;\
if (val > 0x3FFU || hi > 0x3FFU)\
ERROR\
val += (hi<<10) + 0x10000;\
}\
}\

Convert a UTF-16 character (2 or 4 bytes) to its 32-bit UCS-4 encoded form.

Parameters
valOutput value, must be an lvalue of type uint32_t.
GET_16BITExpression returning two bytes of UTF-16 data converted to native byte order. Evaluated one or two times.
ERRORExpression to be evaluated on invalid input, typically a goto statement.

Definition at line 334 of file common.h.

#define PUT_UTF8 (   val,
  tmp,
  PUT_BYTE 
)
Value:
{\
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\
}\
}\
}
av_const int av_log2(unsigned v)
Reverse the order of the bits of an 8-bits unsigned integer.

Convert a 32-bit Unicode character to its UTF-8 encoded form (up to 4 bytes long).

Parameters
valis an input-only argument and should be of type uint32_t. It holds a UCS-4 encoded Unicode character that is to be converted to UTF-8. If val is given as a function it is executed only once.
tmpis a temporary variable and should be of type uint8_t. It represents an intermediate value during conversion that is to be output by PUT_BYTE.
PUT_BYTEwrites 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.

Definition at line 362 of file common.h.

#define PUT_UTF16 (   val,
  tmp,
  PUT_16BIT 
)
Value:
{\
uint32_t in = val;\
if (in < 0x10000) {\
tmp = in;\
PUT_16BIT\
} else {\
tmp = 0xD800 | ((in - 0x10000) >> 10);\
PUT_16BIT\
tmp = 0xDC00 | ((in - 0x10000) & 0x3FF);\
PUT_16BIT\
}\
}\

Convert a 32-bit Unicode character to its UTF-16 encoded form (2 or 4 bytes).

Parameters
valis an input-only argument and should be of type uint32_t. It holds a UCS-4 encoded Unicode character that is to be converted to UTF-16. If val is given as a function it is executed only once.
tmpis a temporary variable and should be of type uint16_t. It represents an intermediate value during conversion that is to be output by PUT_16BIT.
PUT_16BITwrites the converted UTF-16 data to any proper destination in desired endianness. 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 1 or 2 times depending on input character.

Definition at line 396 of file common.h.

Function Documentation

av_const int av_log2 ( unsigned  v)

Reverse the order of the bits of an 8-bits unsigned integer.

Referenced by av_ceil_log2_c().

av_const int av_log2_16bit ( unsigned  v)
static av_always_inline av_const int av_clip_c ( int  a,
int  amin,
int  amax 
)
static

Clip a signed integer value into the amin-amax range.

Parameters
avalue to clip
aminminimum value of the clip range
amaxmaximum value of the clip range
Returns
clipped value

Definition at line 105 of file common.h.

static av_always_inline av_const int64_t av_clip64_c ( int64_t  a,
int64_t  amin,
int64_t  amax 
)
static

Clip a signed 64bit integer value into the amin-amax range.

Parameters
avalue to clip
aminminimum value of the clip range
amaxmaximum value of the clip range
Returns
clipped value

Definition at line 122 of file common.h.

static av_always_inline av_const uint8_t av_clip_uint8_c ( int  a)
static

Clip a signed integer value into the 0-255 range.

Parameters
avalue to clip
Returns
clipped value

Definition at line 137 of file common.h.

static av_always_inline av_const int8_t av_clip_int8_c ( int  a)
static

Clip a signed integer value into the -128,127 range.

Parameters
avalue to clip
Returns
clipped value

Definition at line 148 of file common.h.

static av_always_inline av_const uint16_t av_clip_uint16_c ( int  a)
static

Clip a signed integer value into the 0-65535 range.

Parameters
avalue to clip
Returns
clipped value

Definition at line 159 of file common.h.

static av_always_inline av_const int16_t av_clip_int16_c ( int  a)
static

Clip a signed integer value into the -32768,32767 range.

Parameters
avalue to clip
Returns
clipped value

Definition at line 170 of file common.h.

static av_always_inline av_const int32_t av_clipl_int32_c ( int64_t  a)
static

Clip a signed 64-bit integer value into the -2147483648,2147483647 range.

Parameters
avalue to clip
Returns
clipped value

Definition at line 181 of file common.h.

static av_always_inline av_const unsigned av_clip_uintp2_c ( int  a,
int  p 
)
static

Clip a signed integer to an unsigned power of two range.

Parameters
avalue to clip
pbit position to clip at
Returns
clipped value

Definition at line 193 of file common.h.

static av_always_inline int av_sat_add32_c ( int  a,
int  b 
)
static

Add two signed 32-bit values with saturation.

Parameters
aone value
banother value
Returns
sum with signed saturation

Definition at line 206 of file common.h.

static av_always_inline int av_sat_dadd32_c ( int  a,
int  b 
)
static

Add a doubled value to another value with saturation at both stages.

Parameters
afirst value
bvalue doubled and added to a
Returns
sum with signed saturation

Definition at line 218 of file common.h.

static av_always_inline av_const float av_clipf_c ( float  a,
float  amin,
float  amax 
)
static

Clip a float value into the amin-amax range.

Parameters
avalue to clip
aminminimum value of the clip range
amaxmaximum value of the clip range
Returns
clipped value

Definition at line 230 of file common.h.

static av_always_inline av_const double av_clipd_c ( double  a,
double  amin,
double  amax 
)
static

Clip a double value into the amin-amax range.

Parameters
avalue to clip
aminminimum value of the clip range
amaxmaximum value of the clip range
Returns
clipped value

Definition at line 247 of file common.h.

static av_always_inline av_const int av_ceil_log2_c ( int  x)
static

Compute ceil(log2(x)).

Parameters
xvalue used to compute ceil(log2(x))
Returns
computed ceiling of log2(x)

Definition at line 261 of file common.h.

static av_always_inline av_const int av_popcount_c ( uint32_t  x)
static

Count number of bits set to one in x.

Parameters
xvalue to count bits of
Returns
the number of bits set to one in x

Definition at line 271 of file common.h.

static av_always_inline av_const int av_popcount64_c ( uint64_t  x)
static

Count number of bits set to one in x.

Parameters
xvalue to count bits of
Returns
the number of bits set to one in x

Definition at line 285 of file common.h.