ffmpeg/libavcodec/common.h

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#ifndef COMMON_H
#define COMMON_H
#define FFMPEG_VERSION_INT 0x000406
#define FFMPEG_VERSION "0.4.6"
#if defined(WIN32) && !defined(__MINGW32__) && !defined(__CYGWIN__)
#define CONFIG_WIN32
#endif
//#define ALT_BITSTREAM_WRITER
//#define ALIGNED_BITSTREAM_WRITER
//#define ALT_BITSTREAM_READER
//#define ALIGNED_BITSTREAM
#define FAST_GET_FIRST_VLC
//#define DUMP_STREAM // only works with the ALT_BITSTREAM_READER
#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 <errno.h>
#include <math.h>
#ifndef ENODATA
#define ENODATA 61
#endif
#endif /* HAVE_AV_CONFIG_H */
#ifdef CONFIG_WIN32
/* windows */
typedef unsigned short UINT16;
typedef signed short INT16;
typedef unsigned char UINT8;
typedef unsigned int UINT32;
typedef unsigned __int64 UINT64;
typedef signed char INT8;
typedef signed int INT32;
typedef signed __int64 INT64;
typedef UINT8 uint8_t;
typedef INT8 int8_t;
typedef UINT16 uint16_t;
typedef INT16 int16_t;
typedef UINT32 uint32_t;
typedef INT32 int32_t;
#ifndef __MINGW32__
#define INT64_C(c) (c ## i64)
#define UINT64_C(c) (c ## i64)
#define inline __inline
/*
Disable warning messages:
warning C4244: '=' : conversion from 'double' to 'float', possible loss of data
warning C4305: 'argument' : truncation from 'const double' to 'float'
*/
#pragma warning( disable : 4244 )
#pragma warning( disable : 4305 )
#else
#define INT64_C(c) (c ## LL)
#define UINT64_C(c) (c ## ULL)
#endif /* __MINGW32__ */
#define M_PI 3.14159265358979323846
#define M_SQRT2 1.41421356237309504880 /* sqrt(2) */
#ifdef _DEBUG
#define DEBUG
#endif
// code from bits/byteswap.h (C) 1997, 1998 Free Software Foundation, Inc.
#define bswap_32(x) \
((((x) & 0xff000000) >> 24) | (((x) & 0x00ff0000) >> 8) | \
(((x) & 0x0000ff00) << 8) | (((x) & 0x000000ff) << 24))
#define be2me_32(x) bswap_32(x)
#define snprintf _snprintf
#ifndef __MINGW32__
/* no config.h with VC */
#define CONFIG_ENCODERS 1
#define CONFIG_DECODERS 1
#define CONFIG_AC3 1
#endif
#else
/* unix */
#include <inttypes.h>
#ifndef __WINE_WINDEF16_H
/* workaround for typedef conflict in MPlayer (wine typedefs) */
typedef unsigned short UINT16;
typedef signed short INT16;
#endif
typedef unsigned char UINT8;
typedef unsigned int UINT32;
typedef unsigned long long UINT64;
typedef signed char INT8;
typedef signed int INT32;
typedef signed long long INT64;
#ifdef HAVE_AV_CONFIG_H
#ifdef __FreeBSD__
#include <sys/param.h>
#endif
#ifndef INT64_C
#define INT64_C(c) (c ## LL)
#define UINT64_C(c) (c ## ULL)
#endif
#include "bswap.h"
#ifdef USE_FASTMEMCPY
#include "fastmemcpy.h"
#endif
#endif /* HAVE_AV_CONFIG_H */
#endif /* !CONFIG_WIN32 */
/* debug stuff */
#ifdef HAVE_AV_CONFIG_H
#ifndef DEBUG
#define NDEBUG
#endif
#include <assert.h>
/* dprintf macros */
#if defined(CONFIG_WIN32) && !defined(__MINGW32__)
inline void dprintf(const char* fmt,...) {}
#else
#ifdef DEBUG
#define dprintf(fmt,args...) printf(fmt, ## args)
#else
#define dprintf(fmt,args...)
#endif
#endif /* !CONFIG_WIN32 */
#endif /* HAVE_AV_CONFIG_H */
/* assume b>0 */
#define ROUNDED_DIV(a,b) (((a)>0 ? (a) + ((b)>>1) : (a) - ((b)>>1))/(b))
#define ABS(a) ((a) >= 0 ? (a) : (-(a)))
/* bit output */
struct PutBitContext;
typedef void (*WriteDataFunc)(void *, UINT8 *, int);
typedef struct PutBitContext {
#ifdef ALT_BITSTREAM_WRITER
UINT8 *buf, *buf_end;
int index;
#else
UINT32 bit_buf;
int bit_left;
UINT8 *buf, *buf_ptr, *buf_end;
#endif
INT64 data_out_size; /* in bytes */
} PutBitContext;
void init_put_bits(PutBitContext *s,
UINT8 *buffer, int buffer_size,
void *opaque,
void (*write_data)(void *, UINT8 *, int));
INT64 get_bit_count(PutBitContext *s); /* XXX: change function name */
void align_put_bits(PutBitContext *s);
void flush_put_bits(PutBitContext *s);
void put_string(PutBitContext * pbc, char *s);
/* jpeg specific put_bits */
void jflush_put_bits(PutBitContext *s);
/* bit input */
typedef struct GetBitContext {
#ifdef ALT_BITSTREAM_READER
int index;
UINT8 *buffer;
#else
UINT32 bit_buf;
int bit_cnt;
UINT8 *buf, *buf_ptr, *buf_end;
#endif
int size;
} GetBitContext;
static inline int get_bits_count(GetBitContext *s);
typedef struct VLC {
int bits;
INT16 *table_codes;
INT8 *table_bits;
int table_size, table_allocated;
} VLC;
/* used to avoid missaligned exceptions on some archs (alpha, ...) */
#ifdef ARCH_X86
#define unaligned32(a) (*(UINT32*)(a))
#else
#ifdef __GNUC__
static inline uint32_t unaligned32(const void *v) {
struct Unaligned {
uint32_t i;
} __attribute__((packed));
return ((const struct Unaligned *) v)->i;
}
#elif defined(__DECC)
static inline uint32_t unaligned32(const void *v) {
return *(const __unaligned uint32_t *) v;
}
#else
static inline uint32_t unaligned32(const void *v) {
return *(const uint32_t *) v;
}
#endif
#endif //!ARCH_X86
#ifndef ALT_BITSTREAM_WRITER
static inline void put_bits(PutBitContext *s, int n, unsigned int value)
{
unsigned int bit_buf;
int bit_left;
#ifdef STATS
st_out_bit_counts[st_current_index] += n;
#endif
// printf("put_bits=%d %x\n", n, value);
assert(n == 32 || value < (1U << n));
bit_buf = s->bit_buf;
bit_left = s->bit_left;
// printf("n=%d value=%x cnt=%d buf=%x\n", n, value, bit_cnt, bit_buf);
/* XXX: optimize */
if (n < bit_left) {
bit_buf = (bit_buf<<n) | value;
bit_left-=n;
} else {
bit_buf<<=bit_left;
bit_buf |= value >> (n - bit_left);
*(UINT32 *)s->buf_ptr = be2me_32(bit_buf);
//printf("bitbuf = %08x\n", bit_buf);
s->buf_ptr+=4;
bit_left+=32 - n;
bit_buf = value;
}
s->bit_buf = bit_buf;
s->bit_left = bit_left;
}
#endif
#ifdef ALT_BITSTREAM_WRITER
static inline void put_bits(PutBitContext *s, int n, unsigned int value)
{
#ifdef ALIGNED_BITSTREAM_WRITER
#ifdef ARCH_X86
asm volatile(
"movl %0, %%ecx \n\t"
"xorl %%eax, %%eax \n\t"
"shrdl %%cl, %1, %%eax \n\t"
"shrl %%cl, %1 \n\t"
"movl %0, %%ecx \n\t"
"shrl $3, %%ecx \n\t"
"andl $0xFFFFFFFC, %%ecx \n\t"
"bswapl %1 \n\t"
"orl %1, (%2, %%ecx) \n\t"
"bswapl %%eax \n\t"
"addl %3, %0 \n\t"
"movl %%eax, 4(%2, %%ecx) \n\t"
: "=&r" (s->index), "=&r" (value)
: "r" (s->buf), "r" (n), "0" (s->index), "1" (value<<(-n))
: "%eax", "%ecx"
);
#else
int index= s->index;
uint32_t *ptr= ((uint32_t *)s->buf)+(index>>5);
value<<= 32-n;
ptr[0] |= be2me_32(value>>(index&31));
ptr[1] = be2me_32(value<<(32-(index&31)));
//if(n>24) printf("%d %d\n", n, value);
index+= n;
s->index= index;
#endif
#else //ALIGNED_BITSTREAM_WRITER
#ifdef ARCH_X86
asm volatile(
"movl $7, %%ecx \n\t"
"andl %0, %%ecx \n\t"
"addl %3, %%ecx \n\t"
"negl %%ecx \n\t"
"shll %%cl, %1 \n\t"
"bswapl %1 \n\t"
"movl %0, %%ecx \n\t"
"shrl $3, %%ecx \n\t"
"orl %1, (%%ecx, %2) \n\t"
"addl %3, %0 \n\t"
"movl $0, 4(%%ecx, %2) \n\t"
: "=&r" (s->index), "=&r" (value)
: "r" (s->buf), "r" (n), "0" (s->index), "1" (value)
: "%ecx"
);
#else
int index= s->index;
uint32_t *ptr= (uint32_t*)(((uint8_t *)s->buf)+(index>>3));
ptr[0] |= be2me_32(value<<(32-n-(index&7) ));
ptr[1] = 0;
//if(n>24) printf("%d %d\n", n, value);
index+= n;
s->index= index;
#endif
#endif //!ALIGNED_BITSTREAM_WRITER
}
#endif
#ifndef ALT_BITSTREAM_WRITER
/* for jpeg : escape 0xff with 0x00 after it */
static inline void jput_bits(PutBitContext *s, int n, unsigned int value)
{
unsigned int bit_buf, b;
int bit_left, i;
assert(n == 32 || value < (1U << n));
bit_buf = s->bit_buf;
bit_left = s->bit_left;
//printf("n=%d value=%x cnt=%d buf=%x\n", n, value, bit_cnt, bit_buf);
/* XXX: optimize */
if (n < bit_left) {
bit_buf = (bit_buf<<n) | value;
bit_left-=n;
} else {
bit_buf<<=bit_left;
bit_buf |= value >> (n - bit_left);
/* handle escape */
for(i=0;i<4;i++) {
b = (bit_buf >> 24);
*(s->buf_ptr++) = b;
if (b == 0xff)
*(s->buf_ptr++) = 0;
bit_buf <<= 8;
}
bit_left+= 32 - n;
bit_buf = value;
}
s->bit_buf = bit_buf;
s->bit_left = bit_left;
}
#endif
#ifdef ALT_BITSTREAM_WRITER
static inline void jput_bits(PutBitContext *s, int n, int value)
{
int index= s->index;
uint32_t *ptr= (uint32_t*)(((uint8_t *)s->buf)+(index>>3));
int v= ptr[0];
//if(n>24) printf("%d %d\n", n, value);
v |= be2me_32(value<<(32-n-(index&7) ));
if(((v+0x01010101)^0xFFFFFFFF)&v&0x80808080)
{
/* handle idiotic (m)jpeg escapes */
uint8_t *bPtr= (uint8_t*)ptr;
int numChecked= ((index+n)>>3) - (index>>3);
v= be2me_32(v);
*(bPtr++)= v>>24;
if((v&0xFF000000)==0xFF000000 && numChecked>0){
*(bPtr++)= 0x00;
index+=8;
}
*(bPtr++)= (v>>16)&0xFF;
if((v&0x00FF0000)==0x00FF0000 && numChecked>1){
*(bPtr++)= 0x00;
index+=8;
}
*(bPtr++)= (v>>8)&0xFF;
if((v&0x0000FF00)==0x0000FF00 && numChecked>2){
*(bPtr++)= 0x00;
index+=8;
}
*(bPtr++)= v&0xFF;
if((v&0x000000FF)==0x000000FF && numChecked>3){
*(bPtr++)= 0x00;
index+=8;
}
*((uint32_t*)bPtr)= 0;
}
else
{
ptr[0] = v;
ptr[1] = 0;
}
index+= n;
s->index= index;
}
#endif
static inline uint8_t* pbBufPtr(PutBitContext *s)
{
#ifdef ALT_BITSTREAM_WRITER
return s->buf + (s->index>>3);
#else
return s->buf_ptr;
#endif
}
void init_get_bits(GetBitContext *s,
UINT8 *buffer, int buffer_size);
#ifndef ALT_BITSTREAM_READER
unsigned int get_bits_long(GetBitContext *s, int n);
unsigned int show_bits_long(GetBitContext *s, int n);
#endif
static inline unsigned int get_bits(GetBitContext *s, int n){
#ifdef ALT_BITSTREAM_READER
#ifdef ALIGNED_BITSTREAM
int index= s->index;
uint32_t result1= be2me_32( ((uint32_t *)s->buffer)[index>>5] );
uint32_t result2= be2me_32( ((uint32_t *)s->buffer)[(index>>5) + 1] );
#ifdef ARCH_X86
asm ("shldl %%cl, %2, %0\n\t"
: "=r" (result1)
: "0" (result1), "r" (result2), "c" (index));
#else
result1<<= (index&0x1F);
result2= (result2>>1) >> (31-(index&0x1F));
result1|= result2;
#endif
result1>>= 32 - n;
index+= n;
s->index= index;
return result1;
#else //ALIGNED_BITSTREAM
int index= s->index;
uint32_t result= be2me_32( unaligned32( ((uint8_t *)s->buffer)+(index>>3) ) );
result<<= (index&0x07);
result>>= 32 - n;
index+= n;
s->index= index;
#ifdef DUMP_STREAM
while(n){
printf("%d", (result>>(n-1))&1);
n--;
}
printf(" ");
#endif
return result;
#endif //!ALIGNED_BITSTREAM
#else //ALT_BITSTREAM_READER
if(s->bit_cnt>=n){
/* most common case here */
unsigned int val = s->bit_buf >> (32 - n);
s->bit_buf <<= n;
s->bit_cnt -= n;
#ifdef STATS
st_bit_counts[st_current_index] += n;
#endif
return val;
}
return get_bits_long(s,n);
#endif //!ALT_BITSTREAM_READER
}
static inline unsigned int get_bits1(GetBitContext *s){
#ifdef ALT_BITSTREAM_READER
int index= s->index;
uint8_t result= s->buffer[ index>>3 ];
result<<= (index&0x07);
result>>= 8 - 1;
index++;
s->index= index;
#ifdef DUMP_STREAM
printf("%d ", result);
#endif
return result;
#else
if(s->bit_cnt>0){
/* most common case here */
unsigned int val = s->bit_buf >> 31;
s->bit_buf <<= 1;
s->bit_cnt--;
#ifdef STATS
st_bit_counts[st_current_index]++;
#endif
return val;
}
return get_bits_long(s,1);
#endif
}
/* This function is identical to get_bits(), the only */
/* diference is that it doesn't touch the buffer */
/* it is usefull to see the buffer. */
static inline unsigned int show_bits(GetBitContext *s, int n)
{
#ifdef ALT_BITSTREAM_READER
#ifdef ALIGNED_BITSTREAM
int index= s->index;
uint32_t result1= be2me_32( ((uint32_t *)s->buffer)[index>>5] );
uint32_t result2= be2me_32( ((uint32_t *)s->buffer)[(index>>5) + 1] );
#ifdef ARCH_X86
asm ("shldl %%cl, %2, %0\n\t"
: "=r" (result1)
: "0" (result1), "r" (result2), "c" (index));
#else
result1<<= (index&0x1F);
result2= (result2>>1) >> (31-(index&0x1F));
result1|= result2;
#endif
result1>>= 32 - n;
return result1;
#else //ALIGNED_BITSTREAM
int index= s->index;
uint32_t result= be2me_32( unaligned32( ((uint8_t *)s->buffer)+(index>>3) ) );
result<<= (index&0x07);
result>>= 32 - n;
return result;
#endif //!ALIGNED_BITSTREAM
#else //ALT_BITSTREAM_READER
if(s->bit_cnt>=n) {
/* most common case here */
unsigned int val = s->bit_buf >> (32 - n);
return val;
}
return show_bits_long(s,n);
#endif //!ALT_BITSTREAM_READER
}
static inline int show_aligned_bits(GetBitContext *s, int offset, int n)
{
#ifdef ALT_BITSTREAM_READER
#ifdef ALIGNED_BITSTREAM
int index= (s->index + offset + 7)&(~7);
uint32_t result1= be2me_32( ((uint32_t *)s->buffer)[index>>5] );
uint32_t result2= be2me_32( ((uint32_t *)s->buffer)[(index>>5) + 1] );
#ifdef ARCH_X86
asm ("shldl %%cl, %2, %0\n\t"
: "=r" (result1)
: "0" (result1), "r" (result2), "c" (index));
#else
result1<<= (index&0x1F);
result2= (result2>>1) >> (31-(index&0x1F));
result1|= result2;
#endif
result1>>= 32 - n;
return result1;
#else //ALIGNED_BITSTREAM
int index= (s->index + offset + 7)>>3;
uint32_t result= be2me_32( unaligned32( ((uint8_t *)s->buffer)+index ) );
result>>= 32 - n;
return result;
#endif //!ALIGNED_BITSTREAM
#else //ALT_BITSTREAM_READER
int index= (get_bits_count(s) + offset + 7)>>3;
uint32_t result= be2me_32( unaligned32( ((uint8_t *)s->buf)+index ) );
result>>= 32 - n;
//printf(" %X %X %d \n", (int)(((uint8_t *)s->buf)+index ), (int)s->buf_ptr, s->bit_cnt);
return result;
#endif //!ALT_BITSTREAM_READER
}
static inline void skip_bits(GetBitContext *s, int n){
#ifdef ALT_BITSTREAM_READER
s->index+= n;
#ifdef DUMP_STREAM
{
int result;
s->index-= n;
result= get_bits(s, n);
}
#endif
#else
if(s->bit_cnt>=n){
/* most common case here */
s->bit_buf <<= n;
s->bit_cnt -= n;
#ifdef STATS
st_bit_counts[st_current_index] += n;
#endif
} else {
get_bits_long(s,n);
}
#endif
}
static inline void skip_bits1(GetBitContext *s){
#ifdef ALT_BITSTREAM_READER
s->index++;
#ifdef DUMP_STREAM
s->index--;
printf("%d ", get_bits1(s));
#endif
#else
if(s->bit_cnt>0){
/* most common case here */
s->bit_buf <<= 1;
s->bit_cnt--;
#ifdef STATS
st_bit_counts[st_current_index]++;
#endif
} else {
get_bits_long(s,1);
}
#endif
}
static inline int get_bits_count(GetBitContext *s)
{
#ifdef ALT_BITSTREAM_READER
return s->index;
#else
return (s->buf_ptr - s->buf) * 8 - s->bit_cnt;
#endif
}
int check_marker(GetBitContext *s, char *msg);
void align_get_bits(GetBitContext *s);
int init_vlc(VLC *vlc, int nb_bits, int nb_codes,
const void *bits, int bits_wrap, int bits_size,
const void *codes, int codes_wrap, int codes_size);
void free_vlc(VLC *vlc);
#ifdef ALT_BITSTREAM_READER
#ifdef ALIGNED_BITSTREAM
#ifdef ARCH_X86
#define SHOW_BITS(s, val, n) \
val= be2me_32( ((uint32_t *)(s)->buffer)[bit_cnt>>5] );\
{uint32_t result2= be2me_32( ((uint32_t *)(s)->buffer)[(bit_cnt>>5) + 1] );\
asm ("shldl %%cl, %2, %0\n\t"\
: "=r" (val)\
: "0" (val), "r" (result2), "c" (bit_cnt));\
((uint32_t)val)>>= 32 - n;}
#else //ARCH_X86
#define SHOW_BITS(s, val, n) \
val= be2me_32( ((uint32_t *)(s)->buffer)[bit_cnt>>5] );\
{uint32_t result2= be2me_32( ((uint32_t *)(s)->buffer)[(bit_cnt>>5) + 1] );\
val<<= (bit_cnt&0x1F);\
result2= (result2>>1) >> (31-(bit_cnt&0x1F));\
val|= result2;\
((uint32_t)val)>>= 32 - n;}
#endif //!ARCH_X86
#else //ALIGNED_BITSTREAM
#define SHOW_BITS(s, val, n) \
val= be2me_32( unaligned32( ((uint8_t *)(s)->buffer)+(bit_cnt>>3) ) );\
val<<= (bit_cnt&0x07);\
((uint32_t)val)>>= 32 - n;
#endif // !ALIGNED_BITSTREAM
#define FLUSH_BITS(n) bit_cnt+=n;
#define SAVE_BITS(s) bit_cnt= (s)->index;
#define RESTORE_BITS(s) (s)->index= bit_cnt;
#else
/* macro to go faster */
/* n must be <= 24 */
/* XXX: optimize buffer end test */
#define SHOW_BITS(s, val, n)\
{\
if (bit_cnt < n && buf_ptr < (s)->buf_end) {\
bit_buf |= *buf_ptr++ << (24 - bit_cnt);\
bit_cnt += 8;\
if (bit_cnt < n && buf_ptr < (s)->buf_end) {\
bit_buf |= *buf_ptr++ << (24 - bit_cnt);\
bit_cnt += 8;\
if (bit_cnt < n && buf_ptr < (s)->buf_end) {\
bit_buf |= *buf_ptr++ << (24 - bit_cnt);\
bit_cnt += 8;\
}\
}\
}\
val = bit_buf >> (32 - n);\
}
/* SHOW_BITS with n1 >= n must be been done before */
#define FLUSH_BITS(n)\
{\
bit_buf <<= n;\
bit_cnt -= n;\
}
#define SAVE_BITS(s) \
{\
bit_cnt = (s)->bit_cnt;\
bit_buf = (s)->bit_buf;\
buf_ptr = (s)->buf_ptr;\
}
#define RESTORE_BITS(s) \
{\
(s)->buf_ptr = buf_ptr;\
(s)->bit_buf = bit_buf;\
(s)->bit_cnt = bit_cnt;\
}
#endif // !ALT_BITSTREAM_READER
static inline int get_vlc(GetBitContext *s, VLC *vlc)
{
int code, n, nb_bits, index;
INT16 *table_codes;
INT8 *table_bits;
int bit_cnt;
#ifndef ALT_BITSTREAM_READER
UINT32 bit_buf;
UINT8 *buf_ptr;
#endif
SAVE_BITS(s);
nb_bits = vlc->bits;
table_codes = vlc->table_codes;
table_bits = vlc->table_bits;
#ifdef FAST_GET_FIRST_VLC
SHOW_BITS(s, index, nb_bits);
code = table_codes[index];
n = table_bits[index];
if (n > 0) {
/* most common case (90%)*/
FLUSH_BITS(n);
#ifdef DUMP_STREAM
{
int n= bit_cnt - s->index;
skip_bits(s, n);
RESTORE_BITS(s);
}
#endif
RESTORE_BITS(s);
return code;
} else if (n == 0) {
return -1;
} else {
FLUSH_BITS(nb_bits);
nb_bits = -n;
table_codes = vlc->table_codes + code;
table_bits = vlc->table_bits + code;
}
#endif
for(;;) {
SHOW_BITS(s, index, nb_bits);
code = table_codes[index];
n = table_bits[index];
if (n > 0) {
/* most common case */
FLUSH_BITS(n);
#ifdef STATS
st_bit_counts[st_current_index] += n;
#endif
break;
} else if (n == 0) {
return -1;
} else {
FLUSH_BITS(nb_bits);
#ifdef STATS
st_bit_counts[st_current_index] += nb_bits;
#endif
nb_bits = -n;
table_codes = vlc->table_codes + code;
table_bits = vlc->table_bits + code;
}
}
#ifdef DUMP_STREAM
{
int n= bit_cnt - s->index;
skip_bits(s, n);
RESTORE_BITS(s);
}
#endif
RESTORE_BITS(s);
return code;
}
/* define it to include statistics code (useful only for optimizing
codec efficiency */
//#define STATS
#ifdef STATS
enum {
ST_UNKNOWN,
ST_DC,
ST_INTRA_AC,
ST_INTER_AC,
ST_INTRA_MB,
ST_INTER_MB,
ST_MV,
ST_NB,
};
extern int st_current_index;
extern unsigned int st_bit_counts[ST_NB];
extern unsigned int st_out_bit_counts[ST_NB];
void print_stats(void);
#endif
/* misc math functions */
static inline int av_log2(unsigned int v)
{
int n;
n = 0;
if (v & 0xffff0000) {
v >>= 16;
n += 16;
}
if (v & 0xff00) {
v >>= 8;
n += 8;
}
if (v & 0xf0) {
v >>= 4;
n += 4;
}
if (v & 0xc) {
v >>= 2;
n += 2;
}
if (v & 0x2) {
n++;
}
return n;
}
/* median of 3 */
static inline int mid_pred(int a, int b, int c)
{
int vmin, vmax;
vmax = vmin = a;
if (b < vmin)
vmin = b;
else
vmax = b;
if (c < vmin)
vmin = c;
else if (c > vmax)
vmax = c;
return a + b + c - vmin - vmax;
}
static inline int clip(int a, int amin, int amax)
{
if (a < amin)
return amin;
else if (a > amax)
return amax;
else
return a;
}
/* memory */
void *av_malloc(int size);
void *av_mallocz(int size);
void av_free(void *ptr);
#define av_freep(p) do { av_free(*p); *p = NULL; } while (0)
/* math */
int ff_gcd(int a, int b);
#define CLAMP_TO_8BIT(d) ((d > 0xff) ? 0xff : (d < 0) ? 0 : d)
#endif