timestamp.cpp

用VC++编译的13818-5 MPEG2系统层分析代码

/* Copyright (C) 1995, Tektronix Inc. All Rights Reserved.
 *
 *   Usage Restrictions
 *
 * License is granted to copy, to use, and to make and to use derivative
 * works for research and evaluation purposes only.
 *
 *   Disclaimer of Warranty
 *
 * These software programs are available to the user without any license
 * fee or royalty on an "as is" basis.  Tektronix Inc. disclaims any and
 * all warranties, whether express, implied, or statuary, including any
 * implied warranties or merchantability or of fitness for a particular
 * purpose.  In no event shall the copyright-holder 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 Tektronix Inc. does not represent or warrant that the programs
 * furnished hereunder are free of infringement of any third-party
 * patents.
*/

/* TimeStamp implementation */

#include "TimeStamp.H"
#include "Utilities.H"

extern "C"
{
#include <stdio.h>
}

TimeStamp90::TimeStamp90 (long b)
{
  bit32 = 0;
  bits0_31 = b;
}

TimeStamp90::TimeStamp90 (long b, int b32)
{
  bit32 = b32;
  bits0_31 = b;
}

TimeStamp90::TimeStamp90 (const TimeStamp27& a)
{
  bit32 = a.bit32;
  bits0_31 = a.bits0_31;
}

void TimeStamp90::print ()
{
  // FIX -- the following is a cheap hack
  if (bit32) printf("2*");
  printf("%d", bits0_31);
}

TimeStamp27::TimeStamp27 () : TimeStamp90 (0)
{
  ext = 0;
}

TimeStamp27::TimeStamp27 (long b) : TimeStamp90(b / 300)
{
  ext = b % 300;
}

TimeStamp27::TimeStamp27 (long b, short e) : TimeStamp90(b)
{
  ext = e;
}

TimeStamp27::TimeStamp27 (long b, int b32, short e) : TimeStamp90(b, b32)
{
  ext = e;
}

TimeStamp27& TimeStamp27::operator = (const TimeStamp27& a)
{
  bit32 = a.bit32;
  bits0_31 = a.bits0_31;
  ext = a.ext;
  return *this;
}

TimeStamp27& TimeStamp27::operator = (long a)
{
  bit32 = 0;
  bits0_31 = a / 300;
  ext = a % 300;
  return *this;
}

TimeStamp27 operator + (TimeStamp27& a, TimeStamp27& b)
{
  TimeStamp27 r;
  int extsum = a.ext + b.ext;  
  r.bits0_31 = a.bits0_31 + b.bits0_31;
  r.bits0_31 += (extsum > 299) ? 1 : 0;
  r.ext = extsum % 300;
  return r;
}

TimeStamp27 operator - (TimeStamp27& a, TimeStamp27& b)
{
  TimeStamp27 r;
  if (b > a)
    {
      sys_message("can't return negative difference in TimeStamp27 operator-");
      return r;
    }
  if (a.ext < b.ext)
    { // borrow case
      r.ext = a.ext + 300 - b.ext;
      r.bits0_31 = a.bits0_31 - b.bits0_31 - 1;
    }
  else
    {
      r.ext = a.ext - b.ext;
      r.bits0_31 = a.bits0_31 - b.bits0_31;
    }
  return r;
}

int operator > (TimeStamp27& a, TimeStamp27& b)
{
  if (a.bits0_31 > b.bits0_31) return 1;
  if (a.bits0_31 < b.bits0_31) return 0;
  if (a.ext > b.ext) return 1;
  if (a.ext < b.ext) return 0;
  return 0;
}

long TimeStamp27::useconds ()
{
  unsigned long t = bits0_31 * 300 + ext;
  return t / 27;
}

void TimeStamp27::print ()
{
  printf("(");
  if (bit32) printf("2*");
  printf("%d", bits0_31);
  printf(",%d)", ext);  
}