uvg266/src/bitstream.h

/**
 * \file
 * \brief Bitstream can be written to one or several bits at a time.
 * 
 * \author Marko Viitanen ( fador@iki.fi ),
 *         Tampere University of Technology,
 *         Department of Pervasive Computing.
 * \author Ari Koivula ( ari@koivu.la ),
 *         Tampere University of Technology,
 *         Department of Pervasive Computing.
 */

#ifndef _BITSTREAM_H
#define _BITSTREAM_H
 
#include "global.h"

 
typedef struct
{
    uint32_t data[32];
    uint8_t  cur_byte;
    uint8_t  cur_bit;
    FILE*    output;
    uint8_t* buffer;
    uint32_t buffer_pos;
    uint32_t bufferlen;
} bitstream;

typedef struct
{
  uint8_t len;
  uint32_t value;
} bit_table;

extern bit_table *g_exp_table;

int floor_log2(unsigned int n);
 
void bitstream_alloc(bitstream* stream, uint32_t alloc);
void bitstream_clear_buffer(bitstream* stream);
void bitstream_init(bitstream* stream); 
void bitstream_put(bitstream* stream, uint32_t data, uint8_t bits); 

/* Use macros to force inlining */
#define bitstream_put_ue(stream, data) { bitstream_put(stream,g_exp_table[data].value,g_exp_table[data].len); }
#define bitstream_put_se(stream, data) { uint32_t index=(uint32_t)(((data)<=0)?(-(data))<<1:((data)<<1)-1);    \
                                         bitstream_put(stream,g_exp_table[index].value,g_exp_table[index].len); }

void bitstream_align(bitstream* stream); 
void bitstream_align_zero(bitstream* stream);
void bitstream_flush(bitstream* stream);
void init_exp_golomb(uint32_t len);


/* In debug mode print out some extra info */
#ifdef NOTDEFINED//_DEBUG
/* Counter to keep up with bits written */
static int WRITE_VALUE = 0;
#define WRITE_U(stream, data, bits, name) { printf("%8d  %-40s u(%d) : %d\n",WRITE_VALUE, name,bits,data); bitstream_put(stream,data,bits); WRITE_VALUE++;}
#define WRITE_UE(stream, data, name) { printf("%8d  %-40s ue(v): %d\n",WRITE_VALUE, name,data); bitstream_put_ue(stream,data); WRITE_VALUE++;}
#define WRITE_SE(stream, data, name) { printf("%8d  %-40s se(v): %d\n",WRITE_VALUE, name,data); bitstream_put_se(stream,(data)); WRITE_VALUE++;}
#else
#define WRITE_U(stream, data, bits, name) { bitstream_put(stream,data,bits); }
#define WRITE_UE(stream, data, name) { bitstream_put_ue(stream,data); }
#define WRITE_SE(stream, data, name) { bitstream_put_se(stream,data); }
#endif

 
#endif