fi.helsinki.cs.ohtu.mpeg2
Class ClockOps

java.lang.Object
  fi.helsinki.cs.ohtu.mpeg2.ClockOps

 class ClockOps
extends java.lang.Object

Implements assorted methods to handle the 33-bit 90kHz MPEG system clock values.

Field Summary

static int

TICK_RATE The number of system clock ticks per second

Constructor Summary

private

ClockOps()

Method Summary

static long	add(long t, double s) Adds system clock ticks and seconds.
static long	add(long a, long b) Adds two system clock values.
static boolean	isLessThan(long a, long b) Compares whether the first system clock value is less than (or precedes) the second value.
static long	normalize(long t) Normalizes (that is, gets mod 2^33 - 1) of a system clock value.
static double	toSeconds(long t) Converts system clock ticks to seconds.
static long	toTicks(double s) Converts seconds to system clock ticks.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

TICK_RATE

public static final int TICK_RATE

The number of system clock ticks per second

See Also:

Constant Field Values

Constructor Detail

ClockOps

private ClockOps()

Method Detail

toTicks

public static long toTicks(double s)

Converts seconds to system clock ticks.

Parameters:

s - the seconds to convert

Returns:

the system clock ticks

toSeconds

public static double toSeconds(long t)

Converts system clock ticks to seconds.

Parameters:

t - the system clock ticks

Returns:

the seconds

add

public static long add(long a,
                       long b)

Adds two system clock values.

Parameters:

a - the first system clock value

b - the second system clock value

Returns:

the sum of the system clock values

add

public static long add(long t,
                       double s)

Adds system clock ticks and seconds.

Parameters:

t - the system clock ticks

s - the seconds to add

Returns:

the sum of the ticks and seconds, in ticks

normalize

public static long normalize(long t)

Normalizes (that is, gets mod 2^33 - 1) of a system clock value.

Parameters:

t - the system clock value

Returns:

the normalized system clock value

isLessThan

public static boolean isLessThan(long a,
                                 long b)

Compares whether the first system clock value is less than (or precedes) the second value. As the values can overflow and wrap around, the comparison is slightly tricky. The values are assumed to be less than 2^32 ticks apart. If a - b is at least 2^32, one of the values (not both!) is assumed to have wrapped around.

Parameters:

a - the first system clock value

b - the second system clock value

Returns:

true if a is less than (or precedes) b