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/*
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 * copyright (c) 2004 Michael Niedermayer <michaelni@gmx.at>
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 *
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 * This file is part of FFmpeg.
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 *
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 * FFmpeg is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU Lesser General Public
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 * License as published by the Free Software Foundation; either
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 * version 2.1 of the License, or (at your option) any later version.
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 *
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 * FFmpeg is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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 * Lesser General Public License for more details.
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 *
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 * You should have received a copy of the GNU Lesser General Public
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 * License along with FFmpeg; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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 */
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/**
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 * @file bitstream.h
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 * bitstream api header.
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 */
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#ifndef BITSTREAM_H
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#define BITSTREAM_H
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#include <stdint.h>
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#include <stdlib.h>
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#include <assert.h>
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#include "common.h"
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#include "bswap.h"
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#include "log.h"
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#if defined(ALT_BITSTREAM_READER_LE) && !defined(ALT_BITSTREAM_READER)
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#define ALT_BITSTREAM_READER
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#endif
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//#define ALT_BITSTREAM_WRITER
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//#define ALIGNED_BITSTREAM_WRITER
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#if !defined(LIBMPEG2_BITSTREAM_READER) && !defined(A32_BITSTREAM_READER) && !defined(ALT_BITSTREAM_READER)
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#   ifdef ARCH_ARMV4L
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#       define A32_BITSTREAM_READER
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#   else
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#define ALT_BITSTREAM_READER
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//#define LIBMPEG2_BITSTREAM_READER
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//#define A32_BITSTREAM_READER
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#   endif
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#endif
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#define LIBMPEG2_BITSTREAM_READER_HACK //add BERO
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extern const uint8_t ff_reverse[256];
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#if defined(ARCH_X86)
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// avoid +32 for shift optimization (gcc should do that ...)
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static inline  int32_t NEG_SSR32( int32_t a, int8_t s){
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    asm ("sarl %1, %0\n\t"
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         : "+r" (a)
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         : "ic" ((uint8_t)(-s))
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    );
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    return a;
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}
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static inline uint32_t NEG_USR32(uint32_t a, int8_t s){
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    asm ("shrl %1, %0\n\t"
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         : "+r" (a)
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         : "ic" ((uint8_t)(-s))
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    );
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    return a;
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}
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#else
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#    define NEG_SSR32(a,s) ((( int32_t)(a))>>(32-(s)))
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#    define NEG_USR32(a,s) (((uint32_t)(a))>>(32-(s)))
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#endif
75

    
76
/* bit output */
77

    
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/* buf and buf_end must be present and used by every alternative writer. */
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typedef struct PutBitContext {
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#ifdef ALT_BITSTREAM_WRITER
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    uint8_t *buf, *buf_end;
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    int index;
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#else
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    uint32_t bit_buf;
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    int bit_left;
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    uint8_t *buf, *buf_ptr, *buf_end;
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#endif
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} PutBitContext;
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static inline void init_put_bits(PutBitContext *s, uint8_t *buffer, int buffer_size)
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{
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    if(buffer_size < 0) {
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        buffer_size = 0;
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        buffer = NULL;
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    }
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    s->buf = buffer;
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    s->buf_end = s->buf + buffer_size;
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#ifdef ALT_BITSTREAM_WRITER
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    s->index=0;
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    ((uint32_t*)(s->buf))[0]=0;
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//    memset(buffer, 0, buffer_size);
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#else
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    s->buf_ptr = s->buf;
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    s->bit_left=32;
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    s->bit_buf=0;
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#endif
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}
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110
/* return the number of bits output */
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static inline int put_bits_count(PutBitContext *s)
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{
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#ifdef ALT_BITSTREAM_WRITER
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    return s->index;
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#else
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    return (s->buf_ptr - s->buf) * 8 + 32 - s->bit_left;
117
#endif
118
}
119

    
120
/* pad the end of the output stream with zeros */
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static inline void flush_put_bits(PutBitContext *s)
122
{
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#ifdef ALT_BITSTREAM_WRITER
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    align_put_bits(s);
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#else
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    s->bit_buf<<= s->bit_left;
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    while (s->bit_left < 32) {
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        /* XXX: should test end of buffer */
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        *s->buf_ptr++=s->bit_buf >> 24;
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        s->bit_buf<<=8;
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        s->bit_left+=8;
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    }
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    s->bit_left=32;
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    s->bit_buf=0;
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#endif
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}
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void align_put_bits(PutBitContext *s);
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void ff_put_string(PutBitContext * pbc, char *s, int put_zero);
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void ff_copy_bits(PutBitContext *pb, uint8_t *src, int length);
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/* bit input */
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/* buffer, buffer_end and size_in_bits must be present and used by every reader */
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typedef struct GetBitContext {
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    const uint8_t *buffer, *buffer_end;
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#ifdef ALT_BITSTREAM_READER
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    int index;
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#elif defined LIBMPEG2_BITSTREAM_READER
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    uint8_t *buffer_ptr;
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    uint32_t cache;
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    int bit_count;
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#elif defined A32_BITSTREAM_READER
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    uint32_t *buffer_ptr;
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    uint32_t cache0;
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    uint32_t cache1;
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    int bit_count;
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#endif
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    int size_in_bits;
159
} GetBitContext;
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#define VLC_TYPE int16_t
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163
typedef struct VLC {
164
    int bits;
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    VLC_TYPE (*table)[2]; ///< code, bits
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    int table_size, table_allocated;
167
} VLC;
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typedef struct RL_VLC_ELEM {
170
    int16_t level;
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    int8_t len;
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    uint8_t run;
173
} RL_VLC_ELEM;
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175
#if defined(ARCH_SPARC) || defined(ARCH_ARMV4L) || defined(ARCH_MIPS) || defined(ARCH_BFIN)
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#define UNALIGNED_STORES_ARE_BAD
177
#endif
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/* used to avoid misaligned exceptions on some archs (alpha, ...) */
180
#if defined(ARCH_X86)
181
#    define unaligned16(a) (*(const uint16_t*)(a))
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#    define unaligned32(a) (*(const uint32_t*)(a))
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#    define unaligned64(a) (*(const uint64_t*)(a))
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#else
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#    ifdef __GNUC__
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#    define unaligned(x)                                \
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static inline uint##x##_t unaligned##x(const void *v) { \
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    struct Unaligned {                                  \
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        uint##x##_t i;                                  \
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    } __attribute__((packed));                          \
191
                                                        \
192
    return ((const struct Unaligned *) v)->i;           \
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}
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#    elif defined(__DECC)
195
#    define unaligned(x)                                        \
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static inline uint##x##_t unaligned##x(const void *v) {         \
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    return *(const __unaligned uint##x##_t *) v;                \
198
}
199
#    else
200
#    define unaligned(x)                                        \
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static inline uint##x##_t unaligned##x(const void *v) {         \
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    return *(const uint##x##_t *) v;                            \
203
}
204
#    endif
205
unaligned(16)
206
unaligned(32)
207
unaligned(64)
208
#undef unaligned
209
#endif /* defined(ARCH_X86) */
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211
#ifndef ALT_BITSTREAM_WRITER
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static inline void put_bits(PutBitContext *s, int n, unsigned int value)
213
{
214
    unsigned int bit_buf;
215
    int bit_left;
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217
    //    printf("put_bits=%d %x\n", n, value);
218
    assert(n == 32 || value < (1U << n));
219

    
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    bit_buf = s->bit_buf;
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    bit_left = s->bit_left;
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    //    printf("n=%d value=%x cnt=%d buf=%x\n", n, value, bit_cnt, bit_buf);
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    /* XXX: optimize */
225
    if (n < bit_left) {
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        bit_buf = (bit_buf<<n) | value;
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        bit_left-=n;
228
    } else {
229
        bit_buf<<=bit_left;
230
        bit_buf |= value >> (n - bit_left);
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#ifdef UNALIGNED_STORES_ARE_BAD
232
        if (3 & (intptr_t) s->buf_ptr) {
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            s->buf_ptr[0] = bit_buf >> 24;
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            s->buf_ptr[1] = bit_buf >> 16;
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            s->buf_ptr[2] = bit_buf >>  8;
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            s->buf_ptr[3] = bit_buf      ;
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        } else
238
#endif
239
        *(uint32_t *)s->buf_ptr = be2me_32(bit_buf);
240
        //printf("bitbuf = %08x\n", bit_buf);
241
        s->buf_ptr+=4;
242
        bit_left+=32 - n;
243
        bit_buf = value;
244
    }
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    s->bit_buf = bit_buf;
247
    s->bit_left = bit_left;
248
}
249
#endif
250

    
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252
#ifdef ALT_BITSTREAM_WRITER
253
static inline void put_bits(PutBitContext *s, int n, unsigned int value)
254
{
255
#    ifdef ALIGNED_BITSTREAM_WRITER
256
#        if defined(ARCH_X86)
257
    asm volatile(
258
        "movl %0, %%ecx                 \n\t"
259
        "xorl %%eax, %%eax              \n\t"
260
        "shrdl %%cl, %1, %%eax          \n\t"
261
        "shrl %%cl, %1                  \n\t"
262
        "movl %0, %%ecx                 \n\t"
263
        "shrl $3, %%ecx                 \n\t"
264
        "andl $0xFFFFFFFC, %%ecx        \n\t"
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        "bswapl %1                      \n\t"
266
        "orl %1, (%2, %%ecx)            \n\t"
267
        "bswapl %%eax                   \n\t"
268
        "addl %3, %0                    \n\t"
269
        "movl %%eax, 4(%2, %%ecx)       \n\t"
270
        : "=&r" (s->index), "=&r" (value)
271
        : "r" (s->buf), "r" (n), "0" (s->index), "1" (value<<(-n))
272
        : "%eax", "%ecx"
273
    );
274
#        else
275
    int index= s->index;
276
    uint32_t *ptr= ((uint32_t *)s->buf)+(index>>5);
277

    
278
    value<<= 32-n;
279

    
280
    ptr[0] |= be2me_32(value>>(index&31));
281
    ptr[1]  = be2me_32(value<<(32-(index&31)));
282
//if(n>24) printf("%d %d\n", n, value);
283
    index+= n;
284
    s->index= index;
285
#        endif
286
#    else //ALIGNED_BITSTREAM_WRITER
287
#        if defined(ARCH_X86)
288
    asm volatile(
289
        "movl $7, %%ecx                 \n\t"
290
        "andl %0, %%ecx                 \n\t"
291
        "addl %3, %%ecx                 \n\t"
292
        "negl %%ecx                     \n\t"
293
        "shll %%cl, %1                  \n\t"
294
        "bswapl %1                      \n\t"
295
        "movl %0, %%ecx                 \n\t"
296
        "shrl $3, %%ecx                 \n\t"
297
        "orl %1, (%%ecx, %2)            \n\t"
298
        "addl %3, %0                    \n\t"
299
        "movl $0, 4(%%ecx, %2)          \n\t"
300
        : "=&r" (s->index), "=&r" (value)
301
        : "r" (s->buf), "r" (n), "0" (s->index), "1" (value)
302
        : "%ecx"
303
    );
304
#        else
305
    int index= s->index;
306
    uint32_t *ptr= (uint32_t*)(((uint8_t *)s->buf)+(index>>3));
307

    
308
    ptr[0] |= be2me_32(value<<(32-n-(index&7) ));
309
    ptr[1] = 0;
310
//if(n>24) printf("%d %d\n", n, value);
311
    index+= n;
312
    s->index= index;
313
#        endif
314
#    endif //!ALIGNED_BITSTREAM_WRITER
315
}
316
#endif
317

    
318

    
319
static inline uint8_t* pbBufPtr(PutBitContext *s)
320
{
321
#ifdef ALT_BITSTREAM_WRITER
322
        return s->buf + (s->index>>3);
323
#else
324
        return s->buf_ptr;
325
#endif
326
}
327

    
328
/**
329
 *
330
 * PutBitContext must be flushed & aligned to a byte boundary before calling this.
331
 */
332
static inline void skip_put_bytes(PutBitContext *s, int n){
333
        assert((put_bits_count(s)&7)==0);
334
#ifdef ALT_BITSTREAM_WRITER
335
        FIXME may need some cleaning of the buffer
336
        s->index += n<<3;
337
#else
338
        assert(s->bit_left==32);
339
        s->buf_ptr += n;
340
#endif
341
}
342

    
343
/**
344
 * Skips the given number of bits.
345
 * Must only be used if the actual values in the bitstream do not matter.
346
 */
347
static inline void skip_put_bits(PutBitContext *s, int n){
348
#ifdef ALT_BITSTREAM_WRITER
349
    s->index += n;
350
#else
351
    s->bit_left -= n;
352
    s->buf_ptr-= s->bit_left>>5;
353
    s->bit_left &= 31;
354
#endif
355
}
356

    
357
/**
358
 * Changes the end of the buffer.
359
 */
360
static inline void set_put_bits_buffer_size(PutBitContext *s, int size){
361
    s->buf_end= s->buf + size;
362
}
363

    
364
/* Bitstream reader API docs:
365
name
366
    abritary name which is used as prefix for the internal variables
367

368
gb
369
    getbitcontext
370

371
OPEN_READER(name, gb)
372
    loads gb into local variables
373

374
CLOSE_READER(name, gb)
375
    stores local vars in gb
376

377
UPDATE_CACHE(name, gb)
378
    refills the internal cache from the bitstream
379
    after this call at least MIN_CACHE_BITS will be available,
380

381
GET_CACHE(name, gb)
382
    will output the contents of the internal cache, next bit is MSB of 32 or 64 bit (FIXME 64bit)
383

384
SHOW_UBITS(name, gb, num)
385
    will return the next num bits
386

387
SHOW_SBITS(name, gb, num)
388
    will return the next num bits and do sign extension
389

390
SKIP_BITS(name, gb, num)
391
    will skip over the next num bits
392
    note, this is equivalent to SKIP_CACHE; SKIP_COUNTER
393

394
SKIP_CACHE(name, gb, num)
395
    will remove the next num bits from the cache (note SKIP_COUNTER MUST be called before UPDATE_CACHE / CLOSE_READER)
396

397
SKIP_COUNTER(name, gb, num)
398
    will increment the internal bit counter (see SKIP_CACHE & SKIP_BITS)
399

400
LAST_SKIP_CACHE(name, gb, num)
401
    will remove the next num bits from the cache if it is needed for UPDATE_CACHE otherwise it will do nothing
402

403
LAST_SKIP_BITS(name, gb, num)
404
    is equivalent to SKIP_LAST_CACHE; SKIP_COUNTER
405

406
for examples see get_bits, show_bits, skip_bits, get_vlc
407
*/
408

    
409
static inline int unaligned32_be(const void *v)
410
{
411
#ifdef CONFIG_ALIGN
412
        const uint8_t *p=v;
413
        return (((p[0]<<8) | p[1])<<16) | (p[2]<<8) | (p[3]);
414
#else
415
        return be2me_32( unaligned32(v)); //original
416
#endif
417
}
418

    
419
static inline int unaligned32_le(const void *v)
420
{
421
#ifdef CONFIG_ALIGN
422
       const uint8_t *p=v;
423
       return (((p[3]<<8) | p[2])<<16) | (p[1]<<8) | (p[0]);
424
#else
425
       return le2me_32( unaligned32(v)); //original
426
#endif
427
}
428

    
429
#ifdef ALT_BITSTREAM_READER
430
#   define MIN_CACHE_BITS 25
431

    
432
#   define OPEN_READER(name, gb)\
433
        int name##_index= (gb)->index;\
434
        int name##_cache= 0;\
435

    
436
#   define CLOSE_READER(name, gb)\
437
        (gb)->index= name##_index;\
438

    
439
# ifdef ALT_BITSTREAM_READER_LE
440
#   define UPDATE_CACHE(name, gb)\
441
        name##_cache= unaligned32_le( ((const uint8_t *)(gb)->buffer)+(name##_index>>3) ) >> (name##_index&0x07);\
442

    
443
#   define SKIP_CACHE(name, gb, num)\
444
        name##_cache >>= (num);
445
# else
446
#   define UPDATE_CACHE(name, gb)\
447
        name##_cache= unaligned32_be( ((const uint8_t *)(gb)->buffer)+(name##_index>>3) ) << (name##_index&0x07);\
448

    
449
#   define SKIP_CACHE(name, gb, num)\
450
        name##_cache <<= (num);
451
# endif
452

    
453
// FIXME name?
454
#   define SKIP_COUNTER(name, gb, num)\
455
        name##_index += (num);\
456

    
457
#   define SKIP_BITS(name, gb, num)\
458
        {\
459
            SKIP_CACHE(name, gb, num)\
460
            SKIP_COUNTER(name, gb, num)\
461
        }\
462

    
463
#   define LAST_SKIP_BITS(name, gb, num) SKIP_COUNTER(name, gb, num)
464
#   define LAST_SKIP_CACHE(name, gb, num) ;
465

    
466
# ifdef ALT_BITSTREAM_READER_LE
467
#   define SHOW_UBITS(name, gb, num)\
468
        ((name##_cache) & (NEG_USR32(0xffffffff,num)))
469

    
470
#   define SHOW_SBITS(name, gb, num)\
471
        NEG_SSR32((name##_cache)<<(32-(num)), num)
472
# else
473
#   define SHOW_UBITS(name, gb, num)\
474
        NEG_USR32(name##_cache, num)
475

    
476
#   define SHOW_SBITS(name, gb, num)\
477
        NEG_SSR32(name##_cache, num)
478
# endif
479

    
480
#   define GET_CACHE(name, gb)\
481
        ((uint32_t)name##_cache)
482

    
483
static inline int get_bits_count(GetBitContext *s){
484
    return s->index;
485
}
486

    
487
static inline void skip_bits_long(GetBitContext *s, int n){
488
    s->index += n;
489
}
490

    
491
#elif defined LIBMPEG2_BITSTREAM_READER
492
//libmpeg2 like reader
493

    
494
#   define MIN_CACHE_BITS 17
495

    
496
#   define OPEN_READER(name, gb)\
497
        int name##_bit_count=(gb)->bit_count;\
498
        int name##_cache= (gb)->cache;\
499
        uint8_t * name##_buffer_ptr=(gb)->buffer_ptr;\
500

    
501
#   define CLOSE_READER(name, gb)\
502
        (gb)->bit_count= name##_bit_count;\
503
        (gb)->cache= name##_cache;\
504
        (gb)->buffer_ptr= name##_buffer_ptr;\
505

    
506
#ifdef LIBMPEG2_BITSTREAM_READER_HACK
507

    
508
#   define UPDATE_CACHE(name, gb)\
509
    if(name##_bit_count >= 0){\
510
        name##_cache+= (int)be2me_16(*(uint16_t*)name##_buffer_ptr) << name##_bit_count;\
511
        name##_buffer_ptr += 2;\
512
        name##_bit_count-= 16;\
513
    }\
514

    
515
#else
516

    
517
#   define UPDATE_CACHE(name, gb)\
518
    if(name##_bit_count >= 0){\
519
        name##_cache+= ((name##_buffer_ptr[0]<<8) + name##_buffer_ptr[1]) << name##_bit_count;\
520
        name##_buffer_ptr+=2;\
521
        name##_bit_count-= 16;\
522
    }\
523

    
524
#endif
525

    
526
#   define SKIP_CACHE(name, gb, num)\
527
        name##_cache <<= (num);\
528

    
529
#   define SKIP_COUNTER(name, gb, num)\
530
        name##_bit_count += (num);\
531

    
532
#   define SKIP_BITS(name, gb, num)\
533
        {\
534
            SKIP_CACHE(name, gb, num)\
535
            SKIP_COUNTER(name, gb, num)\
536
        }\
537

    
538
#   define LAST_SKIP_BITS(name, gb, num) SKIP_BITS(name, gb, num)
539
#   define LAST_SKIP_CACHE(name, gb, num) SKIP_CACHE(name, gb, num)
540

    
541
#   define SHOW_UBITS(name, gb, num)\
542
        NEG_USR32(name##_cache, num)
543

    
544
#   define SHOW_SBITS(name, gb, num)\
545
        NEG_SSR32(name##_cache, num)
546

    
547
#   define GET_CACHE(name, gb)\
548
        ((uint32_t)name##_cache)
549

    
550
static inline int get_bits_count(GetBitContext *s){
551
    return (s->buffer_ptr - s->buffer)*8 - 16 + s->bit_count;
552
}
553

    
554
static inline void skip_bits_long(GetBitContext *s, int n){
555
    OPEN_READER(re, s)
556
    re_bit_count += n;
557
    re_buffer_ptr += 2*(re_bit_count>>4);
558
    re_bit_count &= 15;
559
    re_cache = ((re_buffer_ptr[-2]<<8) + re_buffer_ptr[-1]) << (16+re_bit_count);
560
    UPDATE_CACHE(re, s)
561
    CLOSE_READER(re, s)
562
}
563

    
564
#elif defined A32_BITSTREAM_READER
565

    
566
#   define MIN_CACHE_BITS 32
567

    
568
#   define OPEN_READER(name, gb)\
569
        int name##_bit_count=(gb)->bit_count;\
570
        uint32_t name##_cache0= (gb)->cache0;\
571
        uint32_t name##_cache1= (gb)->cache1;\
572
        uint32_t * name##_buffer_ptr=(gb)->buffer_ptr;\
573

    
574
#   define CLOSE_READER(name, gb)\
575
        (gb)->bit_count= name##_bit_count;\
576
        (gb)->cache0= name##_cache0;\
577
        (gb)->cache1= name##_cache1;\
578
        (gb)->buffer_ptr= name##_buffer_ptr;\
579

    
580
#   define UPDATE_CACHE(name, gb)\
581
    if(name##_bit_count > 0){\
582
        const uint32_t next= be2me_32( *name##_buffer_ptr );\
583
        name##_cache0 |= NEG_USR32(next,name##_bit_count);\
584
        name##_cache1 |= next<<name##_bit_count;\
585
        name##_buffer_ptr++;\
586
        name##_bit_count-= 32;\
587
    }\
588

    
589
#if defined(ARCH_X86)
590
#   define SKIP_CACHE(name, gb, num)\
591
        asm(\
592
            "shldl %2, %1, %0          \n\t"\
593
            "shll %2, %1               \n\t"\
594
            : "+r" (name##_cache0), "+r" (name##_cache1)\
595
            : "Ic" ((uint8_t)(num))\
596
           );
597
#else
598
#   define SKIP_CACHE(name, gb, num)\
599
        name##_cache0 <<= (num);\
600
        name##_cache0 |= NEG_USR32(name##_cache1,num);\
601
        name##_cache1 <<= (num);
602
#endif
603

    
604
#   define SKIP_COUNTER(name, gb, num)\
605
        name##_bit_count += (num);\
606

    
607
#   define SKIP_BITS(name, gb, num)\
608
        {\
609
            SKIP_CACHE(name, gb, num)\
610
            SKIP_COUNTER(name, gb, num)\
611
        }\
612

    
613
#   define LAST_SKIP_BITS(name, gb, num) SKIP_BITS(name, gb, num)
614
#   define LAST_SKIP_CACHE(name, gb, num) SKIP_CACHE(name, gb, num)
615

    
616
#   define SHOW_UBITS(name, gb, num)\
617
        NEG_USR32(name##_cache0, num)
618

    
619
#   define SHOW_SBITS(name, gb, num)\
620
        NEG_SSR32(name##_cache0, num)
621

    
622
#   define GET_CACHE(name, gb)\
623
        (name##_cache0)
624

    
625
static inline int get_bits_count(GetBitContext *s){
626
    return ((uint8_t*)s->buffer_ptr - s->buffer)*8 - 32 + s->bit_count;
627
}
628

    
629
static inline void skip_bits_long(GetBitContext *s, int n){
630
    OPEN_READER(re, s)
631
    re_bit_count += n;
632
    re_buffer_ptr += re_bit_count>>5;
633
    re_bit_count &= 31;
634
    re_cache0 = be2me_32( re_buffer_ptr[-1] ) << re_bit_count;
635
    re_cache1 = 0;
636
    UPDATE_CACHE(re, s)
637
    CLOSE_READER(re, s)
638
}
639

    
640
#endif
641

    
642
/**
643
 * read mpeg1 dc style vlc (sign bit + mantisse with no MSB).
644
 * if MSB not set it is negative
645
 * @param n length in bits
646
 * @author BERO
647
 */
648
static inline int get_xbits(GetBitContext *s, int n){
649
    register int sign;
650
    register int32_t cache;
651
    OPEN_READER(re, s)
652
    UPDATE_CACHE(re, s)
653
    cache = GET_CACHE(re,s);
654
    sign=(~cache)>>31;
655
    LAST_SKIP_BITS(re, s, n)
656
    CLOSE_READER(re, s)
657
    return (NEG_USR32(sign ^ cache, n) ^ sign) - sign;
658
}
659

    
660
static inline int get_sbits(GetBitContext *s, int n){
661
    register int tmp;
662
    OPEN_READER(re, s)
663
    UPDATE_CACHE(re, s)
664
    tmp= SHOW_SBITS(re, s, n);
665
    LAST_SKIP_BITS(re, s, n)
666
    CLOSE_READER(re, s)
667
    return tmp;
668
}
669

    
670
/**
671
 * reads 1-17 bits.
672
 * Note, the alt bitstream reader can read up to 25 bits, but the libmpeg2 reader can't
673
 */
674
static inline unsigned int get_bits(GetBitContext *s, int n){
675
    register int tmp;
676
    OPEN_READER(re, s)
677
    UPDATE_CACHE(re, s)
678
    tmp= SHOW_UBITS(re, s, n);
679
    LAST_SKIP_BITS(re, s, n)
680
    CLOSE_READER(re, s)
681
    return tmp;
682
}
683

    
684
/**
685
 * shows 1-17 bits.
686
 * Note, the alt bitstream reader can read up to 25 bits, but the libmpeg2 reader can't
687
 */
688
static inline unsigned int show_bits(GetBitContext *s, int n){
689
    register int tmp;
690
    OPEN_READER(re, s)
691
    UPDATE_CACHE(re, s)
692
    tmp= SHOW_UBITS(re, s, n);
693
//    CLOSE_READER(re, s)
694
    return tmp;
695
}
696

    
697
static inline void skip_bits(GetBitContext *s, int n){
698
 //Note gcc seems to optimize this to s->index+=n for the ALT_READER :))
699
    OPEN_READER(re, s)
700
    UPDATE_CACHE(re, s)
701
    LAST_SKIP_BITS(re, s, n)
702
    CLOSE_READER(re, s)
703
}
704

    
705
static inline unsigned int get_bits1(GetBitContext *s){
706
#ifdef ALT_BITSTREAM_READER
707
    int index= s->index;
708
    uint8_t result= s->buffer[ index>>3 ];
709
#ifdef ALT_BITSTREAM_READER_LE
710
    result>>= (index&0x07);
711
    result&= 1;
712
#else
713
    result<<= (index&0x07);
714
    result>>= 8 - 1;
715
#endif
716
    index++;
717
    s->index= index;
718

    
719
    return result;
720
#else
721
    return get_bits(s, 1);
722
#endif
723
}
724

    
725
static inline unsigned int show_bits1(GetBitContext *s){
726
    return show_bits(s, 1);
727
}
728

    
729
static inline void skip_bits1(GetBitContext *s){
730
    skip_bits(s, 1);
731
}
732

    
733
/**
734
 * reads 0-32 bits.
735
 */
736
static inline unsigned int get_bits_long(GetBitContext *s, int n){
737
    if(n<=17) return get_bits(s, n);
738
    else{
739
#ifdef ALT_BITSTREAM_READER_LE
740
        int ret= get_bits(s, 16);
741
        return ret | (get_bits(s, n-16) << 16);
742
#else
743
        int ret= get_bits(s, 16) << (n-16);
744
        return ret | get_bits(s, n-16);
745
#endif
746
    }
747
}
748

    
749
/**
750
 * shows 0-32 bits.
751
 */
752
static inline unsigned int show_bits_long(GetBitContext *s, int n){
753
    if(n<=17) return show_bits(s, n);
754
    else{
755
        GetBitContext gb= *s;
756
        int ret= get_bits_long(s, n);
757
        *s= gb;
758
        return ret;
759
    }
760
}
761

    
762
static inline int check_marker(GetBitContext *s, const char *msg)
763
{
764
    int bit= get_bits1(s);
765
    if(!bit)
766
        av_log(NULL, AV_LOG_INFO, "Marker bit missing %s\n", msg);
767

    
768
    return bit;
769
}
770

    
771
/**
772
 * init GetBitContext.
773
 * @param buffer bitstream buffer, must be FF_INPUT_BUFFER_PADDING_SIZE bytes larger then the actual read bits
774
 * because some optimized bitstream readers read 32 or 64 bit at once and could read over the end
775
 * @param bit_size the size of the buffer in bits
776
 */
777
static inline void init_get_bits(GetBitContext *s,
778
                   const uint8_t *buffer, int bit_size)
779
{
780
    int buffer_size= (bit_size+7)>>3;
781
    if(buffer_size < 0 || bit_size < 0) {
782
        buffer_size = bit_size = 0;
783
        buffer = NULL;
784
    }
785

    
786
    s->buffer= buffer;
787
    s->size_in_bits= bit_size;
788
    s->buffer_end= buffer + buffer_size;
789
#ifdef ALT_BITSTREAM_READER
790
    s->index=0;
791
#elif defined LIBMPEG2_BITSTREAM_READER
792
    s->buffer_ptr = (uint8_t*)((intptr_t)buffer&(~1));
793
    s->bit_count = 16 + 8*((intptr_t)buffer&1);
794
    skip_bits_long(s, 0);
795
#elif defined A32_BITSTREAM_READER
796
    s->buffer_ptr = (uint32_t*)((intptr_t)buffer&(~3));
797
    s->bit_count = 32 + 8*((intptr_t)buffer&3);
798
    skip_bits_long(s, 0);
799
#endif
800
}
801

    
802
static inline void align_get_bits(GetBitContext *s)
803
{
804
    int n= (-get_bits_count(s)) & 7;
805
    if(n) skip_bits(s, n);
806
}
807

    
808
#define init_vlc(vlc, nb_bits, nb_codes,\
809
                 bits, bits_wrap, bits_size,\
810
                 codes, codes_wrap, codes_size,\
811
                 flags)\
812
        init_vlc_sparse(vlc, nb_bits, nb_codes,\
813
                 bits, bits_wrap, bits_size,\
814
                 codes, codes_wrap, codes_size,\
815
                 NULL, 0, 0, flags)
816

    
817
int init_vlc_sparse(VLC *vlc, int nb_bits, int nb_codes,
818
             const void *bits, int bits_wrap, int bits_size,
819
             const void *codes, int codes_wrap, int codes_size,
820
             const void *symbols, int symbols_wrap, int symbols_size,
821
             int flags);
822
#define INIT_VLC_USE_STATIC 1
823
#define INIT_VLC_LE         2
824
void free_vlc(VLC *vlc);
825

    
826
/**
827
 *
828
 * if the vlc code is invalid and max_depth=1 than no bits will be removed
829
 * if the vlc code is invalid and max_depth>1 than the number of bits removed
830
 * is undefined
831
 */
832
#define GET_VLC(code, name, gb, table, bits, max_depth)\
833
{\
834
    int n, index, nb_bits;\
835
\
836
    index= SHOW_UBITS(name, gb, bits);\
837
    code = table[index][0];\
838
    n    = table[index][1];\
839
\
840
    if(max_depth > 1 && n < 0){\
841
        LAST_SKIP_BITS(name, gb, bits)\
842
        UPDATE_CACHE(name, gb)\
843
\
844
        nb_bits = -n;\
845
\
846
        index= SHOW_UBITS(name, gb, nb_bits) + code;\
847
        code = table[index][0];\
848
        n    = table[index][1];\
849
        if(max_depth > 2 && n < 0){\
850
            LAST_SKIP_BITS(name, gb, nb_bits)\
851
            UPDATE_CACHE(name, gb)\
852
\
853
            nb_bits = -n;\
854
\
855
            index= SHOW_UBITS(name, gb, nb_bits) + code;\
856
            code = table[index][0];\
857
            n    = table[index][1];\
858
        }\
859
    }\
860
    SKIP_BITS(name, gb, n)\
861
}
862

    
863
#define GET_RL_VLC(level, run, name, gb, table, bits, max_depth, need_update)\
864
{\
865
    int n, index, nb_bits;\
866
\
867
    index= SHOW_UBITS(name, gb, bits);\
868
    level = table[index].level;\
869
    n     = table[index].len;\
870
\
871
    if(max_depth > 1 && n < 0){\
872
        SKIP_BITS(name, gb, bits)\
873
        if(need_update){\
874
            UPDATE_CACHE(name, gb)\
875
        }\
876
\
877
        nb_bits = -n;\
878
\
879
        index= SHOW_UBITS(name, gb, nb_bits) + level;\
880
        level = table[index].level;\
881
        n     = table[index].len;\
882
    }\
883
    run= table[index].run;\
884
    SKIP_BITS(name, gb, n)\
885
}
886

    
887

    
888
/**
889
 * parses a vlc code, faster then get_vlc()
890
 * @param bits is the number of bits which will be read at once, must be
891
 *             identical to nb_bits in init_vlc()
892
 * @param max_depth is the number of times bits bits must be read to completely
893
 *                  read the longest vlc code
894
 *                  = (max_vlc_length + bits - 1) / bits
895
 */
896
static av_always_inline int get_vlc2(GetBitContext *s, VLC_TYPE (*table)[2],
897
                                  int bits, int max_depth)
898
{
899
    int code;
900

    
901
    OPEN_READER(re, s)
902
    UPDATE_CACHE(re, s)
903

    
904
    GET_VLC(code, re, s, table, bits, max_depth)
905

    
906
    CLOSE_READER(re, s)
907
    return code;
908
}
909

    
910
//#define TRACE
911

    
912
#ifdef TRACE
913
static inline void print_bin(int bits, int n){
914
    int i;
915

    
916
    for(i=n-1; i>=0; i--){
917
        av_log(NULL, AV_LOG_DEBUG, "%d", (bits>>i)&1);
918
    }
919
    for(i=n; i<24; i++)
920
        av_log(NULL, AV_LOG_DEBUG, " ");
921
}
922

    
923
static inline int get_bits_trace(GetBitContext *s, int n, char *file, const char *func, int line){
924
    int r= get_bits(s, n);
925

    
926
    print_bin(r, n);
927
    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);
928
    return r;
929
}
930
static inline int get_vlc_trace(GetBitContext *s, VLC_TYPE (*table)[2], int bits, int max_depth, char *file, const char *func, int line){
931
    int show= show_bits(s, 24);
932
    int pos= get_bits_count(s);
933
    int r= get_vlc2(s, table, bits, max_depth);
934
    int len= get_bits_count(s) - pos;
935
    int bits2= show>>(24-len);
936

    
937
    print_bin(bits2, len);
938

    
939
    av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d vlc @%5d in %s %s:%d\n", bits2, len, r, pos, file, func, line);
940
    return r;
941
}
942
static inline int get_xbits_trace(GetBitContext *s, int n, char *file, const char *func, int line){
943
    int show= show_bits(s, n);
944
    int r= get_xbits(s, n);
945

    
946
    print_bin(show, n);
947
    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);
948
    return r;
949
}
950

    
951
#define get_bits(s, n)  get_bits_trace(s, n, __FILE__, __PRETTY_FUNCTION__, __LINE__)
952
#define get_bits1(s)    get_bits_trace(s, 1, __FILE__, __PRETTY_FUNCTION__, __LINE__)
953
#define get_xbits(s, n) get_xbits_trace(s, n, __FILE__, __PRETTY_FUNCTION__, __LINE__)
954
#define get_vlc(s, vlc)            get_vlc_trace(s, (vlc)->table, (vlc)->bits, 3, __FILE__, __PRETTY_FUNCTION__, __LINE__)
955
#define get_vlc2(s, tab, bits, max) get_vlc_trace(s, tab, bits, max, __FILE__, __PRETTY_FUNCTION__, __LINE__)
956

    
957
#define tprintf(p, ...) av_log(p, AV_LOG_DEBUG, __VA_ARGS__)
958

    
959
#else //TRACE
960
#define tprintf(p, ...) {}
961
#endif
962

    
963
static inline int decode012(GetBitContext *gb){
964
    int n;
965
    n = get_bits1(gb);
966
    if (n == 0)
967
        return 0;
968
    else
969
        return get_bits1(gb) + 1;
970
}
971

    
972
#endif /* BITSTREAM_H */