uvlc.c

h.264/avc 视频编码程序,实现分数像素匹配功能,非原创.

/*
***********************************************************************
* COPYRIGHT AND WARRANTY INFORMATION
*
* Copyright 2001, International Telecommunications Union, Geneva
*
* DISCLAIMER OF WARRANTY
*
* These software programs are available to the user without any
* license fee or royalty on an "as is" basis. The ITU disclaims
* any and all warranties, whether express, implied, or
* statutory, including any implied warranties of merchantability
* or of fitness for a particular purpose.  In no event shall the
* contributor or the ITU be liable for any incidental, punitive, or
* consequential damages of any kind whatsoever arising from the
* use of these programs.
*
* This disclaimer of warranty extends to the user of these programs
* and user's customers, employees, agents, transferees, successors,
* and assigns.
*
* The ITU does not represent or warrant that the programs furnished
* hereunder are free of infringement of any third-party patents.
* Commercial implementations of ITU-T Recommendations, including
* shareware, may be subject to royalty fees to patent holders.
* Information regarding the ITU-T patent policy is available from
* the ITU Web site at http://www.itu.int.
*
* THIS IS NOT A GRANT OF PATENT RIGHTS - SEE THE ITU-T PATENT POLICY.
************************************************************************
*/

/*!
 ************************************************************************
 * \file uvlc.c
 *
 * \brief
 *    UVLC support functions
 *
 * \author
 *    Main contributors (see contributors.h for copyright, address and affiliation details)
 *    - Inge Lille-Lang鴜                <[e-mail]>
 *    - Detlev Marpe                     <[e-mail]>
 *    - Gabi Blaettermann             <[e-mail]>
 ************************************************************************
 */
#include "contributors.h"

#include <math.h>
#include <memory.h>
#include <string.h>

#include "global.h"
#include "uvlc.h"
#include "elements.h"
#include "bitsbuf.h"
#include "header.h"


// A little trick to avoid those horrible #if TRACE all over the source code
#if TRACE
#define SYMTRACESTRING(s) strncpy(sym.tracestring,s,TRACESTRING_SIZE)
#else
#define SYMTRACESTRING(s) // do nothing
#endif

extern void tracebits(const char *trace_str,  int len,  int info,int value1,
    int value2) ;

/*!
 ************************************************************************
 * \brief
 *    linfo
 * \par Input:
 *    lenght and info
 * \par Output:
 *    number in the code table
 ************************************************************************
 */
void linfo(int len, int info, int *value1, int *dummy)
{
  *value1 = (int)pow(2,(len/2))+info-1; // *value1 = (int)(2<<(len>>1))+info-1;
}

/*!
 ************************************************************************
 * \par Input:
 *    lenght and info
 * \par Output:
 *    signed mvd
 ************************************************************************
 */
void linfo_mvd(int len, int info, int *signed_mvd, int *dummy)
{
  int n;
  n = (int)pow(2,(len/2))+info-1;
  *signed_mvd = (n+1)/2;
  if((n & 0x01)==0)                           // lsb is signed bit
    *signed_mvd = -*signed_mvd;
}

/*!
 ************************************************************************
 * \par Input:
 *    lenght and info
 * \par Output:
 *    cbp (intra)
 ************************************************************************
 */
void linfo_cbp_intra(int len,int info,int *cbp, int *dummy)
{
  extern const byte NCBP[48][2];
    int cbp_idx;
  linfo(len,info,&cbp_idx,dummy);
    *cbp=NCBP[cbp_idx][0];
}

/*!
 ************************************************************************
 * \par Input:
 *    lenght and info
 * \par Output:
 *    cbp (inter)
 ************************************************************************
 */
void linfo_cbp_inter(int len,int info,int *cbp, int *dummy)
{
  extern const byte NCBP[48][2];
  int cbp_idx;
  linfo(len,info,&cbp_idx,dummy);
    *cbp=NCBP[cbp_idx][1];
}

/*!
 ************************************************************************
 * \par Input:
 *    lenght and info
 * \par Output:
 *    signed mvd
 ************************************************************************
 */
void linfo_dquant(int len,  int info, int *signed_dquant, int *dummy)
{
  int n;
  n = (int)pow(2,(len/2))+info-1;
  *signed_dquant = (n+1)/2;
  if((n & 0x01)==0)                           // lsb is signed bit
    *signed_dquant = -*signed_dquant;
}

/*!
 ************************************************************************
 * \par Input:
 *    lenght and info
 * \par Output:
 *    level, run
 ************************************************************************
 */
void linfo_levrun_inter(int len, int info, int *level, int *irun)
{
  int l2;
  int inf;
  if (len<=9)
  {
    l2=mmax(0,len/2-1);
    inf=info/2;
    *level=NTAB1[l2][inf][0];
    *irun=NTAB1[l2][inf][1];
    if ((info&0x01)==1)
      *level=-*level;                   // make sign
  }
  else                                  // if len > 9, skip using the array
  {
    *irun=(info&0x1e)>>1;
    *level = LEVRUN1[*irun] + info/32 + (int)pow(2,len/2 - 5);
    if ((info&0x01)==1)
      *level=-*level;
  }
    if (len == 1) // EOB
        *level = 0;
}

/*!
 ************************************************************************
 * \par Input:
 *    lenght and info
 * \par Output:
 *    level, run
 ************************************************************************
 */
void linfo_levrun_intra(int len, int info, int *level,  int *irun)
{
  int l2;
  int inf;

  if (len<=9)
  {
    l2=mmax(0,len/2-1);
    inf=info/2;
    *level=NTAB2[l2][inf][0];
    *irun=NTAB2[l2][inf][1];
    if ((info&0x01)==1)
      *level=-*level;                 // make sign
  }
  else                                  // if len > 9, skip using the array
  {
    *irun=(info&0x0e)>>1;
    *level = LEVRUN2[*irun] + info/16 + (int)pow(2,len/2-4) -1;
    if ((info&0x01)==1)
      *level=-*level;
  }
    if (len == 1) // EOB
        *level = 0;
}


/*!
 ************************************************************************
 * \par Input:
 *    lenght and info
 * \par Output:
 *    level, run
 ************************************************************************
 */
void linfo_levrun_c2x2(int len, int info, int *level, int *irun)
{
  int l2;
  int inf;

  if (len<=5)
  {
    l2=mmax(0,len/2-1);
    inf=info/2;
    *level=NTAB3[l2][inf][0];
    *irun=NTAB3[l2][inf][1];
    if ((info&0x01)==1)
      *level=-*level;                 // make sign
  }
  else                                  // if len > 5, skip using the array
  {
    *irun=(info&0x06)>>1;
    *level = LEVRUN3[*irun] + info/8 + (int)pow(2,len/2 - 3);
    if ((info&0x01)==1)
      *level=-*level;
  }
  if (len == 1) // EOB
    *level = 0;
}


/*!
 ************************************************************************
 * \brief
 *    readSliceUVLC
 *
 * \par
 *    Slice Headers can start on every byte aligned position, provided zero-stuffing.
 *    This is implemented here in such a way that a slice header can be trailed by
 *    any number of 0 bits.
 *
 * \return
 *    readSliceUVLC returns -1 in case of problems, or oen of SOP, SOS, EOS in case of success
 ************************************************************************
 */
int readSliceUVLC(struct img_par *img, struct inp_par *inp)
{
  Slice *currSlice = img->currentSlice;
  DataPartition *dP;