com.sun.tv.media

Class GainControlAdapter

java.lang.Object

com.sun.tv.media.GainControlAdapter

All Implemented Interfaces:

Control, GainControl

public class GainControlAdapter
extends Object
implements GainControl

This class is a part of the porting layer implementation for JavaTV GainControlAdapter implements javax.media.GainControl. GainControlAdapter provides methods for 1. manipulating the amplitude of the audio signal and performing math required to map linear gain specifiers to decibels. The relationship between a linear gain multiplier and the gain specified in decibels is: value = pow(10.0, gainDB/20.0) 2. registering, unregistering and informing registered listeners about changes in gain value of the audio signal by posting a GainChangeEvent 3. manipulating the muted state of the audio signal.

Constructor Summary

Constructors

Constructor and Description
GainControlAdapter(boolean mute) constructs a GainControlAdapter object.

Method Summary

Methods

Modifier and Type	Method and Description
void	addGainChangeListener(GainChangeListener listener) Registers a listener for gain change update events.
Component	getControlComponent() This method has to be defined by non-abstarct classes that implement Control interface.
float	getDB() returns the current gain in dB.
float	getLevel() Get the current gain as a value between 0.0 and 1.0
boolean	getMute() retrieves the muted state of the audio signal.
protected void	informListeners() Sends all registered listeners a GainChangeEvent object notifying the listeners about gain change in the GainControl
void	removeGainChangeListener(GainChangeListener listener) Removes a listener from the list of listeners for gain change events.
float	setDB(float gain) sets the gain in decibels.
float	setLevel(float level) Set the gain using a floating point scale with values between 0.0 and 1.0.
void	setMute(boolean mute) sets the muted state of the audio signal.

Methods inherited from class java.lang.Object

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

Constructor Detail

GainControlAdapter

public GainControlAdapter(boolean mute)

constructs a GainControlAdapter object. The gain initially is set to a default value of 0.2f using floating point scale.

Parameters:

mute - specifies whether audio signal is initially muted (true) or unmuted (false)

Method Detail

setMute

public void setMute(boolean mute)

sets the muted state of the audio signal.

Specified by:

setMute in interface GainControl

Parameters:

mute - specifies whether audio is set to be muted (true) or unmuted (false)

getMute

public boolean getMute()

retrieves the muted state of the audio signal.

Specified by:

getMute in interface GainControl

Returns:

muted state

setDB

public float setDB(float gain)

sets the gain in decibels.

Specified by:

setDB in interface GainControl

Parameters:

gain - if positive, the audio signal is amplified from the default level; if gain is negative, the audio signal is attenuated from the default; if gain is 0, the audio signal is set to the default level return the gain in dB.

Returns:

The gain that was actually set.

getDB

public float getDB()

returns the current gain in dB.

Specified by:

getDB in interface GainControl

Returns:

The gain in dB.

setLevel

public float setLevel(float level)

Set the gain using a floating point scale with values between 0.0 and 1.0. 0.0 is silence; 1.0 is the loudest. Informs listeners about gain change

Specified by:

setLevel in interface GainControl

Parameters:

level - The new gain value specified in the level scale.

Returns:

The level that was actually set.

getLevel

public float getLevel()

Get the current gain as a value between 0.0 and 1.0

Specified by:

getLevel in interface GainControl

Returns:

The gain in the level scale (0.0-1.0).

addGainChangeListener

public void addGainChangeListener(GainChangeListener listener)

Registers a listener for gain change update events. A GainChangeEvent is posted when the gain for the GainControlis changed

Specified by:

addGainChangeListener in interface GainControl

Parameters:

listener - The listener for gain change events

removeGainChangeListener

public void removeGainChangeListener(GainChangeListener listener)

Removes a listener from the list of listeners for gain change events.

Specified by:

removeGainChangeListener in interface GainControl

Parameters:

listener - The listener to be removed from the list of listeners for gain change events

getControlComponent

public Component getControlComponent()

This method has to be defined by non-abstarct classes that implement Control interface. Full JMF's implementation the method returns a slider control to manipulate the gain level for all players. JMF Lite's implementation returns null to allow a TV Player to implement the control in a form most suitable for the TV Player.

Specified by:

getControlComponent in interface Control

Returns:

null

informListeners

protected void informListeners()

Sends all registered listeners a GainChangeEvent object notifying the listeners about gain change in the GainControl