FFmpeg/libavcodec/common.h
Arpi 612476ef9b get_bits() specialization, gives 4\speedup
Originally committed as revision 32 to svn://svn.ffmpeg.org/ffmpeg/trunk
2001-08-04 00:46:50 +00:00

229 lines
4.7 KiB
C

#ifndef COMMON_H
#define COMMON_H
#ifdef HAVE_AV_CONFIG_H
#include "../config.h"
#endif
#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;
/* bit output */
struct PutBitContext;
typedef void (*WriteDataFunc)(void *, UINT8 *, int);
typedef struct PutBitContext {
UINT32 bit_buf;
int bit_cnt;
UINT8 *buf, *buf_ptr, *buf_end;
long long data_out_size; /* in bytes */
void *opaque;
WriteDataFunc write_data;
} PutBitContext;
void init_put_bits(PutBitContext *s,
UINT8 *buffer, int buffer_size,
void *opaque,
void (*write_data)(void *, UINT8 *, int));
void put_bits(PutBitContext *s, int n, unsigned int value);
long long get_bit_count(PutBitContext *s);
void align_put_bits(PutBitContext *s);
void flush_put_bits(PutBitContext *s);
/* jpeg specific put_bits */
void jput_bits(PutBitContext *s, int n, unsigned int value);
void jflush_put_bits(PutBitContext *s);
/* bit input */
typedef struct GetBitContext {
UINT32 bit_buf;
int bit_cnt;
UINT8 *buf, *buf_ptr, *buf_end;
} GetBitContext;
typedef struct VLC {
int bits;
INT16 *table_codes;
INT8 *table_bits;
int table_size, table_allocated;
} VLC;
void init_get_bits(GetBitContext *s,
UINT8 *buffer, int buffer_size);
unsigned int get_bits_long(GetBitContext *s, int n);
static inline unsigned int get_bits(GetBitContext *s, int n){
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);
}
static inline unsigned int get_bits1(GetBitContext *s){
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);
}
static inline void skip_bits(GetBitContext *s, int n){
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);
}
}
static inline void skip_bits1(GetBitContext *s){
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);
}
}
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);
int get_vlc(GetBitContext *s, VLC *vlc);
/* 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;\
}
/* 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 */
extern inline int 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;
}
/* memory */
void *av_mallocz(int size);
#endif