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mirror of https://github.com/FFmpeg/FFmpeg.git synced 2024-12-02 03:06:28 +02:00
FFmpeg/libavcodec/bitstream.h
Michael Niedermayer a7702890bd remove STATS code (probably hasnt been used for years ..., and its not completely clear what it was good for anyway)
Originally committed as revision 5689 to svn://svn.ffmpeg.org/ffmpeg/trunk
2006-07-09 10:33:49 +00:00

880 lines
23 KiB
C

/**
* @file bitstream.h
* bitstream api header.
*/
#ifndef BITSTREAM_H
#define BITSTREAM_H
//#define ALT_BITSTREAM_WRITER
//#define ALIGNED_BITSTREAM_WRITER
#define ALT_BITSTREAM_READER
//#define LIBMPEG2_BITSTREAM_READER
//#define A32_BITSTREAM_READER
#define LIBMPEG2_BITSTREAM_READER_HACK //add BERO
extern const uint8_t ff_reverse[256];
#if defined(ARCH_X86) || defined(ARCH_X86_64)
// avoid +32 for shift optimization (gcc should do that ...)
static inline int32_t NEG_SSR32( int32_t a, int8_t s){
asm ("sarl %1, %0\n\t"
: "+r" (a)
: "ic" ((uint8_t)(-s))
);
return a;
}
static inline uint32_t NEG_USR32(uint32_t a, int8_t s){
asm ("shrl %1, %0\n\t"
: "+r" (a)
: "ic" ((uint8_t)(-s))
);
return a;
}
#else
# define NEG_SSR32(a,s) ((( int32_t)(a))>>(32-(s)))
# define NEG_USR32(a,s) (((uint32_t)(a))>>(32-(s)))
#endif
/* bit output */
/* buf and buf_end must be present and used by every alternative writer. */
typedef struct PutBitContext {
#ifdef ALT_BITSTREAM_WRITER
uint8_t *buf, *buf_end;
int index;
#else
uint32_t bit_buf;
int bit_left;
uint8_t *buf, *buf_ptr, *buf_end;
#endif
} PutBitContext;
static inline void init_put_bits(PutBitContext *s, uint8_t *buffer, int buffer_size)
{
if(buffer_size < 0) {
buffer_size = 0;
buffer = NULL;
}
s->buf = buffer;
s->buf_end = s->buf + buffer_size;
#ifdef ALT_BITSTREAM_WRITER
s->index=0;
((uint32_t*)(s->buf))[0]=0;
// memset(buffer, 0, buffer_size);
#else
s->buf_ptr = s->buf;
s->bit_left=32;
s->bit_buf=0;
#endif
}
/* return the number of bits output */
static inline int put_bits_count(PutBitContext *s)
{
#ifdef ALT_BITSTREAM_WRITER
return s->index;
#else
return (s->buf_ptr - s->buf) * 8 + 32 - s->bit_left;
#endif
}
/* pad the end of the output stream with zeros */
static inline void flush_put_bits(PutBitContext *s)
{
#ifdef ALT_BITSTREAM_WRITER
align_put_bits(s);
#else
s->bit_buf<<= s->bit_left;
while (s->bit_left < 32) {
/* XXX: should test end of buffer */
*s->buf_ptr++=s->bit_buf >> 24;
s->bit_buf<<=8;
s->bit_left+=8;
}
s->bit_left=32;
s->bit_buf=0;
#endif
}
void align_put_bits(PutBitContext *s);
void ff_put_string(PutBitContext * pbc, char *s, int put_zero);
/* bit input */
/* buffer, buffer_end and size_in_bits must be present and used by every reader */
typedef struct GetBitContext {
const uint8_t *buffer, *buffer_end;
#ifdef ALT_BITSTREAM_READER
int index;
#elif defined LIBMPEG2_BITSTREAM_READER
uint8_t *buffer_ptr;
uint32_t cache;
int bit_count;
#elif defined A32_BITSTREAM_READER
uint32_t *buffer_ptr;
uint32_t cache0;
uint32_t cache1;
int bit_count;
#endif
int size_in_bits;
} GetBitContext;
#define VLC_TYPE int16_t
typedef struct VLC {
int bits;
VLC_TYPE (*table)[2]; ///< code, bits
int table_size, table_allocated;
} VLC;
typedef struct RL_VLC_ELEM {
int16_t level;
int8_t len;
uint8_t run;
} RL_VLC_ELEM;
#if defined(ARCH_SPARC) || defined(ARCH_ARMV4L) || defined(ARCH_MIPS)
#define UNALIGNED_STORES_ARE_BAD
#endif
/* used to avoid missaligned exceptions on some archs (alpha, ...) */
#if defined(ARCH_X86) || defined(ARCH_X86_64)
# define unaligned16(a) (*(const uint16_t*)(a))
# define unaligned32(a) (*(const uint32_t*)(a))
# define unaligned64(a) (*(const uint64_t*)(a))
#else
# ifdef __GNUC__
# define unaligned(x) \
static inline uint##x##_t unaligned##x(const void *v) { \
struct Unaligned { \
uint##x##_t i; \
} __attribute__((packed)); \
\
return ((const struct Unaligned *) v)->i; \
}
# elif defined(__DECC)
# define unaligned(x) \
static inline uint##x##_t unaligned##x##(const void *v) { \
return *(const __unaligned uint##x##_t *) v; \
}
# else
# define unaligned(x) \
static inline uint##x##_t unaligned##x##(const void *v) { \
return *(const uint##x##_t *) v; \
}
# endif
unaligned(16)
unaligned(32)
unaligned(64)
#undef unaligned
#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;
// 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);
#ifdef UNALIGNED_STORES_ARE_BAD
if (3 & (intptr_t) s->buf_ptr) {
s->buf_ptr[0] = bit_buf >> 24;
s->buf_ptr[1] = bit_buf >> 16;
s->buf_ptr[2] = bit_buf >> 8;
s->buf_ptr[3] = bit_buf ;
} else
#endif
*(uint32_t *)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
# if defined(ARCH_X86) || defined(ARCH_X86_64)
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
# if defined(ARCH_X86) || defined(ARCH_X86_64)
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
static inline uint8_t* pbBufPtr(PutBitContext *s)
{
#ifdef ALT_BITSTREAM_WRITER
return s->buf + (s->index>>3);
#else
return s->buf_ptr;
#endif
}
/**
*
* PutBitContext must be flushed & aligned to a byte boundary before calling this.
*/
static inline void skip_put_bytes(PutBitContext *s, int n){
assert((put_bits_count(s)&7)==0);
#ifdef ALT_BITSTREAM_WRITER
FIXME may need some cleaning of the buffer
s->index += n<<3;
#else
assert(s->bit_left==32);
s->buf_ptr += n;
#endif
}
/**
* skips the given number of bits.
* must only be used if the actual values in the bitstream dont matter
*/
static inline void skip_put_bits(PutBitContext *s, int n){
#ifdef ALT_BITSTREAM_WRITER
s->index += n;
#else
s->bit_left -= n;
s->buf_ptr-= s->bit_left>>5;
s->bit_left &= 31;
#endif
}
/**
* Changes the end of the buffer.
*/
static inline void set_put_bits_buffer_size(PutBitContext *s, int size){
s->buf_end= s->buf + size;
}
/* Bitstream reader API docs:
name
abritary name which is used as prefix for the internal variables
gb
getbitcontext
OPEN_READER(name, gb)
loads gb into local variables
CLOSE_READER(name, gb)
stores local vars in gb
UPDATE_CACHE(name, gb)
refills the internal cache from the bitstream
after this call at least MIN_CACHE_BITS will be available,
GET_CACHE(name, gb)
will output the contents of the internal cache, next bit is MSB of 32 or 64 bit (FIXME 64bit)
SHOW_UBITS(name, gb, num)
will return the next num bits
SHOW_SBITS(name, gb, num)
will return the next num bits and do sign extension
SKIP_BITS(name, gb, num)
will skip over the next num bits
note, this is equivalent to SKIP_CACHE; SKIP_COUNTER
SKIP_CACHE(name, gb, num)
will remove the next num bits from the cache (note SKIP_COUNTER MUST be called before UPDATE_CACHE / CLOSE_READER)
SKIP_COUNTER(name, gb, num)
will increment the internal bit counter (see SKIP_CACHE & SKIP_BITS)
LAST_SKIP_CACHE(name, gb, num)
will remove the next num bits from the cache if it is needed for UPDATE_CACHE otherwise it will do nothing
LAST_SKIP_BITS(name, gb, num)
is equivalent to SKIP_LAST_CACHE; SKIP_COUNTER
for examples see get_bits, show_bits, skip_bits, get_vlc
*/
static inline int unaligned32_be(const void *v)
{
#ifdef CONFIG_ALIGN
const uint8_t *p=v;
return (((p[0]<<8) | p[1])<<16) | (p[2]<<8) | (p[3]);
#else
return be2me_32( unaligned32(v)); //original
#endif
}
static inline int unaligned32_le(const void *v)
{
#ifdef CONFIG_ALIGN
const uint8_t *p=v;
return (((p[3]<<8) | p[2])<<16) | (p[1]<<8) | (p[0]);
#else
return le2me_32( unaligned32(v)); //original
#endif
}
#ifdef ALT_BITSTREAM_READER
# define MIN_CACHE_BITS 25
# define OPEN_READER(name, gb)\
int name##_index= (gb)->index;\
int name##_cache= 0;\
# define CLOSE_READER(name, gb)\
(gb)->index= name##_index;\
# ifdef ALT_BITSTREAM_READER_LE
# define UPDATE_CACHE(name, gb)\
name##_cache= unaligned32_le( ((const uint8_t *)(gb)->buffer)+(name##_index>>3) ) >> (name##_index&0x07);\
# define SKIP_CACHE(name, gb, num)\
name##_cache >>= (num);
# else
# define UPDATE_CACHE(name, gb)\
name##_cache= unaligned32_be( ((const uint8_t *)(gb)->buffer)+(name##_index>>3) ) << (name##_index&0x07);\
# define SKIP_CACHE(name, gb, num)\
name##_cache <<= (num);
# endif
// FIXME name?
# define SKIP_COUNTER(name, gb, num)\
name##_index += (num);\
# define SKIP_BITS(name, gb, num)\
{\
SKIP_CACHE(name, gb, num)\
SKIP_COUNTER(name, gb, num)\
}\
# define LAST_SKIP_BITS(name, gb, num) SKIP_COUNTER(name, gb, num)
# define LAST_SKIP_CACHE(name, gb, num) ;
# ifdef ALT_BITSTREAM_READER_LE
# define SHOW_UBITS(name, gb, num)\
((name##_cache) & (NEG_USR32(0xffffffff,num)))
# else
# define SHOW_UBITS(name, gb, num)\
NEG_USR32(name##_cache, num)
# endif
# define SHOW_SBITS(name, gb, num)\
NEG_SSR32(name##_cache, num)
# define GET_CACHE(name, gb)\
((uint32_t)name##_cache)
static inline int get_bits_count(GetBitContext *s){
return s->index;
}
#elif defined LIBMPEG2_BITSTREAM_READER
//libmpeg2 like reader
# define MIN_CACHE_BITS 17
# define OPEN_READER(name, gb)\
int name##_bit_count=(gb)->bit_count;\
int name##_cache= (gb)->cache;\
uint8_t * name##_buffer_ptr=(gb)->buffer_ptr;\
# define CLOSE_READER(name, gb)\
(gb)->bit_count= name##_bit_count;\
(gb)->cache= name##_cache;\
(gb)->buffer_ptr= name##_buffer_ptr;\
#ifdef LIBMPEG2_BITSTREAM_READER_HACK
# define UPDATE_CACHE(name, gb)\
if(name##_bit_count >= 0){\
name##_cache+= (int)be2me_16(*(uint16_t*)name##_buffer_ptr) << name##_bit_count;\
name##_buffer_ptr += 2;\
name##_bit_count-= 16;\
}\
#else
# define UPDATE_CACHE(name, gb)\
if(name##_bit_count >= 0){\
name##_cache+= ((name##_buffer_ptr[0]<<8) + name##_buffer_ptr[1]) << name##_bit_count;\
name##_buffer_ptr+=2;\
name##_bit_count-= 16;\
}\
#endif
# define SKIP_CACHE(name, gb, num)\
name##_cache <<= (num);\
# define SKIP_COUNTER(name, gb, num)\
name##_bit_count += (num);\
# define SKIP_BITS(name, gb, num)\
{\
SKIP_CACHE(name, gb, num)\
SKIP_COUNTER(name, gb, num)\
}\
# define LAST_SKIP_BITS(name, gb, num) SKIP_BITS(name, gb, num)
# define LAST_SKIP_CACHE(name, gb, num) SKIP_CACHE(name, gb, num)
# define SHOW_UBITS(name, gb, num)\
NEG_USR32(name##_cache, num)
# define SHOW_SBITS(name, gb, num)\
NEG_SSR32(name##_cache, num)
# define GET_CACHE(name, gb)\
((uint32_t)name##_cache)
static inline int get_bits_count(GetBitContext *s){
return (s->buffer_ptr - s->buffer)*8 - 16 + s->bit_count;
}
#elif defined A32_BITSTREAM_READER
# define MIN_CACHE_BITS 32
# define OPEN_READER(name, gb)\
int name##_bit_count=(gb)->bit_count;\
uint32_t name##_cache0= (gb)->cache0;\
uint32_t name##_cache1= (gb)->cache1;\
uint32_t * name##_buffer_ptr=(gb)->buffer_ptr;\
# define CLOSE_READER(name, gb)\
(gb)->bit_count= name##_bit_count;\
(gb)->cache0= name##_cache0;\
(gb)->cache1= name##_cache1;\
(gb)->buffer_ptr= name##_buffer_ptr;\
# define UPDATE_CACHE(name, gb)\
if(name##_bit_count > 0){\
const uint32_t next= be2me_32( *name##_buffer_ptr );\
name##_cache0 |= NEG_USR32(next,name##_bit_count);\
name##_cache1 |= next<<name##_bit_count;\
name##_buffer_ptr++;\
name##_bit_count-= 32;\
}\
#if defined(ARCH_X86) || defined(ARCH_X86_64)
# define SKIP_CACHE(name, gb, num)\
asm(\
"shldl %2, %1, %0 \n\t"\
"shll %2, %1 \n\t"\
: "+r" (name##_cache0), "+r" (name##_cache1)\
: "Ic" ((uint8_t)num)\
);
#else
# define SKIP_CACHE(name, gb, num)\
name##_cache0 <<= (num);\
name##_cache0 |= NEG_USR32(name##_cache1,num);\
name##_cache1 <<= (num);
#endif
# define SKIP_COUNTER(name, gb, num)\
name##_bit_count += (num);\
# define SKIP_BITS(name, gb, num)\
{\
SKIP_CACHE(name, gb, num)\
SKIP_COUNTER(name, gb, num)\
}\
# define LAST_SKIP_BITS(name, gb, num) SKIP_BITS(name, gb, num)
# define LAST_SKIP_CACHE(name, gb, num) SKIP_CACHE(name, gb, num)
# define SHOW_UBITS(name, gb, num)\
NEG_USR32(name##_cache0, num)
# define SHOW_SBITS(name, gb, num)\
NEG_SSR32(name##_cache0, num)
# define GET_CACHE(name, gb)\
(name##_cache0)
static inline int get_bits_count(GetBitContext *s){
return ((uint8_t*)s->buffer_ptr - s->buffer)*8 - 32 + s->bit_count;
}
#endif
/**
* read mpeg1 dc style vlc (sign bit + mantisse with no MSB).
* if MSB not set it is negative
* @param n length in bits
* @author BERO
*/
static inline int get_xbits(GetBitContext *s, int n){
register int sign;
register int32_t cache;
OPEN_READER(re, s)
UPDATE_CACHE(re, s)
cache = GET_CACHE(re,s);
sign=(~cache)>>31;
LAST_SKIP_BITS(re, s, n)
CLOSE_READER(re, s)
return (NEG_USR32(sign ^ cache, n) ^ sign) - sign;
}
static inline int get_sbits(GetBitContext *s, int n){
register int tmp;
OPEN_READER(re, s)
UPDATE_CACHE(re, s)
tmp= SHOW_SBITS(re, s, n);
LAST_SKIP_BITS(re, s, n)
CLOSE_READER(re, s)
return tmp;
}
/**
* reads 0-17 bits.
* Note, the alt bitstream reader can read up to 25 bits, but the libmpeg2 reader can't
*/
static inline unsigned int get_bits(GetBitContext *s, int n){
register int tmp;
OPEN_READER(re, s)
UPDATE_CACHE(re, s)
tmp= SHOW_UBITS(re, s, n);
LAST_SKIP_BITS(re, s, n)
CLOSE_READER(re, s)
return tmp;
}
unsigned int get_bits_long(GetBitContext *s, int n);
/**
* shows 0-17 bits.
* Note, the alt bitstream reader can read up to 25 bits, but the libmpeg2 reader can't
*/
static inline unsigned int show_bits(GetBitContext *s, int n){
register int tmp;
OPEN_READER(re, s)
UPDATE_CACHE(re, s)
tmp= SHOW_UBITS(re, s, n);
// CLOSE_READER(re, s)
return tmp;
}
unsigned int show_bits_long(GetBitContext *s, int n);
static inline void skip_bits(GetBitContext *s, int n){
//Note gcc seems to optimize this to s->index+=n for the ALT_READER :))
OPEN_READER(re, s)
UPDATE_CACHE(re, s)
LAST_SKIP_BITS(re, s, n)
CLOSE_READER(re, s)
}
static inline unsigned int get_bits1(GetBitContext *s){
#ifdef ALT_BITSTREAM_READER
int index= s->index;
uint8_t result= s->buffer[ index>>3 ];
#ifdef ALT_BITSTREAM_READER_LE
result>>= (index&0x07);
result&= 1;
#else
result<<= (index&0x07);
result>>= 8 - 1;
#endif
index++;
s->index= index;
return result;
#else
return get_bits(s, 1);
#endif
}
static inline unsigned int show_bits1(GetBitContext *s){
return show_bits(s, 1);
}
static inline void skip_bits1(GetBitContext *s){
skip_bits(s, 1);
}
/**
* init GetBitContext.
* @param buffer bitstream buffer, must be FF_INPUT_BUFFER_PADDING_SIZE bytes larger then the actual read bits
* because some optimized bitstream readers read 32 or 64 bit at once and could read over the end
* @param bit_size the size of the buffer in bits
*/
static inline void init_get_bits(GetBitContext *s,
const uint8_t *buffer, int bit_size)
{
int buffer_size= (bit_size+7)>>3;
if(buffer_size < 0 || bit_size < 0) {
buffer_size = bit_size = 0;
buffer = NULL;
}
s->buffer= buffer;
s->size_in_bits= bit_size;
s->buffer_end= buffer + buffer_size;
#ifdef ALT_BITSTREAM_READER
s->index=0;
#elif defined LIBMPEG2_BITSTREAM_READER
#ifdef LIBMPEG2_BITSTREAM_READER_HACK
if ((int)buffer&1) {
/* word alignment */
s->cache = (*buffer++)<<24;
s->buffer_ptr = buffer;
s->bit_count = 16-8;
} else
#endif
{
s->buffer_ptr = buffer;
s->bit_count = 16;
s->cache = 0;
}
#elif defined A32_BITSTREAM_READER
s->buffer_ptr = (uint32_t*)buffer;
s->bit_count = 32;
s->cache0 = 0;
s->cache1 = 0;
#endif
{
OPEN_READER(re, s)
UPDATE_CACHE(re, s)
UPDATE_CACHE(re, s)
CLOSE_READER(re, s)
}
#ifdef A32_BITSTREAM_READER
s->cache1 = 0;
#endif
}
int check_marker(GetBitContext *s, const 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,
int flags);
#define INIT_VLC_USE_STATIC 1
#define INIT_VLC_LE 2
void free_vlc(VLC *vlc);
/**
*
* if the vlc code is invalid and max_depth=1 than no bits will be removed
* if the vlc code is invalid and max_depth>1 than the number of bits removed
* is undefined
*/
#define GET_VLC(code, name, gb, table, bits, max_depth)\
{\
int n, index, nb_bits;\
\
index= SHOW_UBITS(name, gb, bits);\
code = table[index][0];\
n = table[index][1];\
\
if(max_depth > 1 && n < 0){\
LAST_SKIP_BITS(name, gb, bits)\
UPDATE_CACHE(name, gb)\
\
nb_bits = -n;\
\
index= SHOW_UBITS(name, gb, nb_bits) + code;\
code = table[index][0];\
n = table[index][1];\
if(max_depth > 2 && n < 0){\
LAST_SKIP_BITS(name, gb, nb_bits)\
UPDATE_CACHE(name, gb)\
\
nb_bits = -n;\
\
index= SHOW_UBITS(name, gb, nb_bits) + code;\
code = table[index][0];\
n = table[index][1];\
}\
}\
SKIP_BITS(name, gb, n)\
}
#define GET_RL_VLC(level, run, name, gb, table, bits, max_depth, need_update)\
{\
int n, index, nb_bits;\
\
index= SHOW_UBITS(name, gb, bits);\
level = table[index].level;\
n = table[index].len;\
\
if(max_depth > 1 && n < 0){\
SKIP_BITS(name, gb, bits)\
if(need_update){\
UPDATE_CACHE(name, gb)\
}\
\
nb_bits = -n;\
\
index= SHOW_UBITS(name, gb, nb_bits) + level;\
level = table[index].level;\
n = table[index].len;\
}\
run= table[index].run;\
SKIP_BITS(name, gb, n)\
}
/**
* parses a vlc code, faster then get_vlc()
* @param bits is the number of bits which will be read at once, must be
* identical to nb_bits in init_vlc()
* @param max_depth is the number of times bits bits must be readed to completly
* read the longest vlc code
* = (max_vlc_length + bits - 1) / bits
*/
static always_inline int get_vlc2(GetBitContext *s, VLC_TYPE (*table)[2],
int bits, int max_depth)
{
int code;
OPEN_READER(re, s)
UPDATE_CACHE(re, s)
GET_VLC(code, re, s, table, bits, max_depth)
CLOSE_READER(re, s)
return code;
}
//#define TRACE
#ifdef TRACE
#include "avcodec.h"
static inline void print_bin(int bits, int n){
int i;
for(i=n-1; i>=0; i--){
av_log(NULL, AV_LOG_DEBUG, "%d", (bits>>i)&1);
}
for(i=n; i<24; i++)
av_log(NULL, AV_LOG_DEBUG, " ");
}
static inline int get_bits_trace(GetBitContext *s, int n, char *file, const char *func, int line){
int r= get_bits(s, n);
print_bin(r, n);
av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d bit @%5d in %s %s:%d\n", r, n, r, get_bits_count(s)-n, file, func, line);
return r;
}
static inline int get_vlc_trace(GetBitContext *s, VLC_TYPE (*table)[2], int bits, int max_depth, char *file, const char *func, int line){
int show= show_bits(s, 24);
int pos= get_bits_count(s);
int r= get_vlc2(s, table, bits, max_depth);
int len= get_bits_count(s) - pos;
int bits2= show>>(24-len);
print_bin(bits2, len);
av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d vlc @%5d in %s %s:%d\n", bits2, len, r, pos, file, func, line);
return r;
}
static inline int get_xbits_trace(GetBitContext *s, int n, char *file, const char *func, int line){
int show= show_bits(s, n);
int r= get_xbits(s, n);
print_bin(show, n);
av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d xbt @%5d in %s %s:%d\n", show, n, r, get_bits_count(s)-n, file, func, line);
return r;
}
#define get_bits(s, n) get_bits_trace(s, n, __FILE__, __PRETTY_FUNCTION__, __LINE__)
#define get_bits1(s) get_bits_trace(s, 1, __FILE__, __PRETTY_FUNCTION__, __LINE__)
#define get_xbits(s, n) get_xbits_trace(s, n, __FILE__, __PRETTY_FUNCTION__, __LINE__)
#define get_vlc(s, vlc) get_vlc_trace(s, (vlc)->table, (vlc)->bits, 3, __FILE__, __PRETTY_FUNCTION__, __LINE__)
#define get_vlc2(s, tab, bits, max) get_vlc_trace(s, tab, bits, max, __FILE__, __PRETTY_FUNCTION__, __LINE__)
#define tprintf(...) av_log(NULL, AV_LOG_DEBUG, __VA_ARGS__)
#else //TRACE
#define tprintf(...) {}
#endif
static inline int decode012(GetBitContext *gb){
int n;
n = get_bits1(gb);
if (n == 0)
return 0;
else
return get_bits1(gb) + 1;
}
#endif /* BITSTREAM_H */