org.jitsi.impl.neomedia.jmfext.media.protocol.wasapi

Class WASAPIStream

java.lang.Object

org.jitsi.impl.neomedia.control.AbstractControls

org.jitsi.impl.neomedia.jmfext.media.protocol.AbstractPushBufferStream<DataSource>

org.jitsi.impl.neomedia.jmfext.media.protocol.wasapi.WASAPIStream

All Implemented Interfaces:

javax.media.Controls, javax.media.protocol.PushBufferStream, javax.media.protocol.SourceStream

public class WASAPIStream
extends AbstractPushBufferStream<DataSource>

Implements a PullBufferStream using Windows Audio Session API (WASAPI) and related Core Audio APIs such as Multimedia Device (MMDevice) API.

Author:

Lyubomir Marinov

Field Summary

Fields

Modifier and Type	Field and Description
protected T	dataSource The DataSource which has created this instance and which contains it as one of its streams.
protected javax.media.control.FormatControl	formatControl The FormatControl which gives access to the Format of the media data provided by this SourceStream and which, optionally, allows setting it.

Fields inherited from class org.jitsi.impl.neomedia.jmfext.media.protocol.AbstractPushBufferStream

PUSH_BUFFER_STREAM_CLASS_NAME, transferHandler

Fields inherited from interface javax.media.protocol.SourceStream

LENGTH_UNKNOWN

Constructor Summary

Constructors

Constructor and Description
WASAPIStream(DataSource dataSource, javax.media.control.FormatControl formatControl) Initializes a new WASAPIStream instance which is to have its Format-related information abstracted by a specific FormatControl.

Method Summary

Modifier and Type	Method and Description
void	close() Releases the resources used by this instance throughout its existence and makes it available for garbage collection.
protected javax.media.Format	doGetFormat() Gets the Format of this AbstractBufferStream as directly known by it.
protected javax.media.Format	doSetFormat(javax.media.Format format) Attempts to set the Format of this AbstractBufferStream.
boolean	endOfStream() Determines whether the end of this SourceStream has been reached.
javax.media.protocol.ContentDescriptor	getContentDescriptor() Gets a ContentDescriptor which describes the type of the content made available by this SourceStream.
long	getContentLength() Gets the length in bytes of the content made available by this SourceStream.
Object[]	getControls() Implements Controls.getControls().
javax.media.Format	getFormat() Gets the Format of the media data made available by this AbstractBufferStream.
void	read(javax.media.Buffer buffer) If resampler is non-null, uses it to resample the media data read from capture or processed into format.
void	start() Starts the transfer of media data from this AbstractBufferStream.
void	stop() Stops the transfer of media data from this AbstractBufferStream.

Methods inherited from class org.jitsi.impl.neomedia.jmfext.media.protocol.AbstractPushBufferStream

setTransferHandler

Methods inherited from class org.jitsi.impl.neomedia.control.AbstractControls

getControl, getControl, queryInterface, queryInterface

Methods inherited from class java.lang.Object

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

Methods inherited from interface javax.media.protocol.SourceStream

endOfStream, getContentDescriptor, getContentLength

Methods inherited from interface javax.media.Controls

getControl, getControls

Field Detail

dataSource

protected final T extends javax.media.protocol.DataSource dataSource

The DataSource which has created this instance and which contains it as one of its streams.

formatControl

protected final javax.media.control.FormatControl formatControl

The FormatControl which gives access to the Format of the media data provided by this SourceStream and which, optionally, allows setting it.

Constructor Detail

WASAPIStream

public WASAPIStream(DataSource dataSource,
                    javax.media.control.FormatControl formatControl)

Initializes a new WASAPIStream instance which is to have its Format-related information abstracted by a specific FormatControl.

Parameters:

dataSource - the DataSource which is initializing the new instance so that it becomes one of its streams

formatControl - the FormatControl which is to abstract the Format-related information of the new instance

Method Detail

doGetFormat

protected javax.media.Format doGetFormat()

Gets the Format of this AbstractBufferStream as directly known by it. Allows extenders to override the Format known to the DataSource which created this instance and possibly provide more details on the currently set Format.

Returns:

the Format of this AbstractBufferStream as directly known by it or null if this AbstractBufferStream does not directly know its Format and it relies on the DataSource which created it to report its Format

getFormat

public javax.media.Format getFormat()

Gets the Format of the media data made available by this AbstractBufferStream. Overrides the super implementation to avoid a deadlock with stop(). The stop() method is generally invoked with a certain synchronization root locked, the implementation of WASAPIStream waits for processThread to quit but processThread indirectly invokes AbstractBufferStream.getFormat() which in turn results in an attempt to lock the mentioned synchronization root i.e. the thread invoking the stop() method and processThread fall into a deadlock.

Specified by:

getFormat in interface javax.media.protocol.PushBufferStream

Returns:

the Format of the media data made available by this AbstractBufferStream

read

public void read(javax.media.Buffer buffer)
          throws IOException

If resampler is non-null, uses it to resample the media data read from capture or processed into format.

Throws:

IOException

start

public void start()
           throws IOException

Starts the transfer of media data from this AbstractBufferStream.

Throws:

IOException - if anything goes wrong while starting the transfer of media data from this AbstractBufferStream

stop

public void stop()
          throws IOException

Stops the transfer of media data from this AbstractBufferStream.

Throws:

IOException - if anything goes wrong while stopping the transfer of media data from this AbstractBufferStream

close

public void close()

Releases the resources used by this instance throughout its existence and makes it available for garbage collection. This instance is considered unusable after closing.

Warning: The method is not invoked by the framework, extenders may choose to invoke it.

doSetFormat

protected javax.media.Format doSetFormat(javax.media.Format format)

Attempts to set the Format of this AbstractBufferStream. Allows extenders to enable setting the Format of an existing AbstractBufferStream (in contract to setting it before the AbstractBufferStream is created by the DataSource which will provide it).

Parameters:

format - the Format to be set as the format of this AbstractBufferStream

Returns:

the Format of this AbstractBufferStream or null if the attempt to set the Format did not succeed and any last-known Format is to be left in effect

endOfStream

public boolean endOfStream()

Determines whether the end of this SourceStream has been reached. The AbstractBufferStream implementation always returns false.

Specified by:

endOfStream in interface javax.media.protocol.SourceStream

Returns:

true if the end of this SourceStream has been reached; otherwise, false

getContentDescriptor

public javax.media.protocol.ContentDescriptor getContentDescriptor()

Gets a ContentDescriptor which describes the type of the content made available by this SourceStream. The AbstractBufferStream implementation always returns a ContentDescriptor with content type equal to ContentDescriptor#RAW.

Specified by:

getContentDescriptor in interface javax.media.protocol.SourceStream

Returns:

a ContentDescriptor which describes the type of the content made available by this SourceStream

getContentLength

public long getContentLength()

Gets the length in bytes of the content made available by this SourceStream. The AbstractBufferStream implementation always returns LENGTH_UNKNOWN.

Specified by:

getContentLength in interface javax.media.protocol.SourceStream

Returns:

the length in bytes of the content made available by this SourceStream if it is known; otherwise, LENGTH_UKNOWN

getControls

public Object[] getControls()

Implements Controls.getControls(). Gets the controls available for this instance.

Specified by:

getControls in interface javax.media.Controls

Returns:

an array of Objects which represent the controls available for this instance