common.h

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        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;
}

/* math */
int ff_gcd(int a, int b);

static inline int ff_sqrt(int a)
{
    int ret=0;
    int s;
    int ret_sq=0;

    for(s=15; s>=0; s--){
        int b= ret_sq + (1<<(s*2)) + (ret<<s)*2;
        if(b<=a){
            ret_sq=b;
            ret+= 1<<s;
        }
    }
    return ret;
}
#if __CPU__ >= 686 && !defined(RUNTIME_CPUDETECT)
#define COPY3_IF_LT(x,y,a,b,c,d)\
asm volatile (\
    "cmpl %0, %3	\n\t"\
    "cmovl %3, %0	\n\t"\
    "cmovl %4, %1	\n\t"\
    "cmovl %5, %2	\n\t"\
    : "+r" (x), "+r" (a), "+r" (c)\
    : "r" (y), "r" (b), "r" (d)\
);
#else
#define COPY3_IF_LT(x,y,a,b,c,d)\
if((y)<(x)){\
     (x)=(y);\
     (a)=(b);\
     (c)=(d);\
}
#endif

#define CLAMP_TO_8BIT(d) ((d > 0xff) ? 0xff : (d < 0) ? 0 : d)

#endif /* HAVE_AV_CONFIG_H */

#endif /* COMMON_H */