MediaTimestamp

public final class MediaTimestamp
extends Object

java.lang.Object
   ↳ android.media.MediaTimestamp


An immutable object that represents the linear correlation between the media time and the system time. It contains the media clock rate, together with the media timestamp of an anchor frame and the system time when that frame was presented or is committed to be presented.

The phrase "present" means that audio/video produced on device is detectable by an external observer off device. The time is based on the implementation's best effort, using whatever knowledge is available to the system, but cannot account for any delay unknown to the implementation. The anchor frame could be any frame, including a just-rendered frame, or even a theoretical or in-between frame, based on the source of the MediaTimestamp. When the anchor frame is a just-rendered one, the media time stands for current position of the playback or recording.

Summary

Fields

public static final MediaTimestamp TIMESTAMP_UNKNOWN

An unknown media timestamp value

Public constructors

MediaTimestamp(long mediaTimeUs, long nanoTimeNs, float clockRate)

Constructor.

Public methods

boolean equals(Object obj)

Indicates whether some other object is "equal to" this one.

long getAnchorMediaTimeUs()

Get the media time of the anchor in microseconds.

long getAnchorSystemNanoTime()

Get the system time corresponding to the media time in nanoseconds.

long getAnchorSytemNanoTime()

This method was deprecated in API level 29. use getAnchorSystemNanoTime() instead.

float getMediaClockRate()

Get the rate of the media clock in relation to the system time.

String toString()

Returns a string representation of the object.

Inherited methods

Fields

TIMESTAMP_UNKNOWN

Added in API level 28
public static final MediaTimestamp TIMESTAMP_UNKNOWN

An unknown media timestamp value

Public constructors

MediaTimestamp

Added in API level 23
public MediaTimestamp (long mediaTimeUs, 
                long nanoTimeNs, 
                float clockRate)

Constructor.

Parameters
mediaTimeUs long: the media time of the anchor in microseconds

nanoTimeNs long: the system time corresponding to the media time in nanoseconds.

clockRate float: the rate of the media clock in relation to the system time. Value is between 0.0f and Float.MAX_VALUE inclusive

Public methods

equals

Added in API level 23
public boolean equals (Object obj)

Indicates whether some other object is "equal to" this one.

The equals method implements an equivalence relation on non-null object references:

  • It is reflexive: for any non-null reference value x, x.equals(x) should return true.
  • It is symmetric: for any non-null reference values x and y, x.equals(y) should return true if and only if y.equals(x) returns true.
  • It is transitive: for any non-null reference values x, y, and z, if x.equals(y) returns true and y.equals(z) returns true, then x.equals(z) should return true.
  • It is consistent: for any non-null reference values x and y, multiple invocations of x.equals(y) consistently return true or consistently return false, provided no information used in equals comparisons on the objects is modified.
  • For any non-null reference value x, x.equals(null) should return false.

An equivalence relation partitions the elements it operates on into equivalence classes; all the members of an equivalence class are equal to each other. Members of an equivalence class are substitutable for each other, at least for some purposes.

Parameters
obj Object: the reference object with which to compare.

Returns
boolean true if this object is the same as the obj argument; false otherwise.

getAnchorMediaTimeUs

Added in API level 23
public long getAnchorMediaTimeUs ()

Get the media time of the anchor in microseconds.

Returns
long

getAnchorSystemNanoTime

Added in API level 29
public long getAnchorSystemNanoTime ()

Get the system time corresponding to the media time in nanoseconds.

Returns
long

getAnchorSytemNanoTime

Added in API level 23
Deprecated in API level 29
public long getAnchorSytemNanoTime ()

This method was deprecated in API level 29.
use getAnchorSystemNanoTime() instead.

Get the system time corresponding to the media time in nanoseconds.

Returns
long

getMediaClockRate

Added in API level 23
public float getMediaClockRate ()

Get the rate of the media clock in relation to the system time.

It is 1.0 if media clock advances in sync with the system clock; greater than 1.0 if media clock is faster than the system clock; less than 1.0 if media clock is slower than the system clock.

Returns
float Value is between 0.0f and Float.MAX_VALUE inclusive

toString

Added in API level 23
public String toString ()

Returns a string representation of the object.

Returns
String a string representation of the object.