Package org.jitsi.impl.neomedia.codec.video.h264

Class DePacketizer

java.lang.Object

net.sf.fmj.media.AbstractControls

net.sf.fmj.media.AbstractPlugIn

net.sf.fmj.media.AbstractCodec

org.jitsi.impl.neomedia.codec.AbstractCodec2

org.jitsi.impl.neomedia.codec.video.h264.DePacketizer

All Implemented Interfaces:

javax.media.Codec, javax.media.Controls, javax.media.PlugIn

public class DePacketizer
extends AbstractCodec2

Implements Codec to represent a depacketizer of H.264 RTP packets into NAL units.

Author:

Lyubomir Marinov, Damian Minkov

Field Summary

Fields inherited from class org.jitsi.impl.neomedia.codec.AbstractCodec2

BUFFER_FLAG_FEC, BUFFER_FLAG_PLC, EMPTY_FORMATS, features, MAX_AUDIO_SEQUENCE_NUMBERS_TO_PLC, SEQUENCE_MAX, SEQUENCE_MIN

Fields inherited from class net.sf.fmj.media.AbstractCodec

inputFormat, inputFormats, opened, outputFormat

Fields inherited from interface javax.media.PlugIn

BUFFER_PROCESSED_FAILED, BUFFER_PROCESSED_OK, INPUT_BUFFER_NOT_CONSUMED, OUTPUT_BUFFER_NOT_FILLED, PLUGIN_TERMINATED

Constructor Summary

Constructors

Constructor	Description
DePacketizer()	Initializes a new DePacketizer instance which is to depacketize H.264 RTP packets into NAL units.

Method Summary

Modifier and Type	Method	Description
protected void	doClose()	Close the Codec.
protected void	doOpen()	Opens this Codec and acquires the resources that it needs to operate.
protected int	doProcess(javax.media.Buffer inBuffer, javax.media.Buffer outBuffer)	Processes (depacketizes) a buffer.
protected javax.media.Format[]	getMatchingOutputFormats(javax.media.Format inputFormat)	Gets the Formats which are supported by this Codec as output when the input is in a specific Format.
static boolean	isKeyFrame(byte[] buf, int off, int len)	Returns true if the buffer contains a H264 key frame at offset offset.
boolean	requestKeyFrame(boolean urgent)	Requests a key frame from the remote peer associated with this DePacketizer using the logic of DePacketizer.
void	setKeyFrameControl(KeyFrameControl keyFrameControl)	Sets the KeyFrameControl to be used by this DePacketizer as a means of control over its key frame-related logic.

Methods inherited from class org.jitsi.impl.neomedia.codec.AbstractCodec2

calculateLostSeqNoCount, close, discardOutputBuffer, getName, getSupportedOutputFormats, incrementSeqNo, matches, open, process, setInputFormat, setOutputFormat, specialize, updateOutput, validateByteArraySize, validateShortArraySize

Methods inherited from class net.sf.fmj.media.AbstractCodec

checkInputBuffer, dump, getInputFormat, getOutputFormat, getSupportedInputFormats, isEOM, propagateEOM

Methods inherited from class net.sf.fmj.media.AbstractPlugIn

reset

Methods inherited from class net.sf.fmj.media.AbstractControls

addControl, getControl, getControls, removeControl

Methods inherited from class java.lang.Object

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

Methods inherited from interface javax.media.Controls

getControl, getControls

Methods inherited from interface javax.media.PlugIn

reset

Constructor Detail

DePacketizer

public DePacketizer()

Initializes a new DePacketizer instance which is to depacketize H.264 RTP packets into NAL units.

Method Detail

doClose

protected void doClose()

Close the Codec.

Specified by:

doClose in class AbstractCodec2

doOpen

protected void doOpen()
               throws javax.media.ResourceUnavailableException

Opens this Codec and acquires the resources that it needs to operate. A call to PlugIn.open() on this instance will result in a call to doOpen only if AbstractCodec.opened is false. All required input and/or output formats are assumed to have been set on this Codec before doOpen is called.

Specified by:

doOpen in class AbstractCodec2

Throws:

javax.media.ResourceUnavailableException - if any of the resources that this Codec needs to operate cannot be acquired

doProcess

protected int doProcess(javax.media.Buffer inBuffer,
                        javax.media.Buffer outBuffer)

Processes (depacketizes) a buffer.

Specified by:

doProcess in class AbstractCodec2

Parameters:

inBuffer - input buffer

outBuffer - output buffer

Returns:

BUFFER_PROCESSED_OK if buffer has been successfully processed

isKeyFrame

public static boolean isKeyFrame(byte[] buf,
                                 int off,
                                 int len)

Returns true if the buffer contains a H264 key frame at offset offset.

Parameters:

buf - the byte buffer to check

off - the offset in the byte buffer where the actuall data starts

len - the length of the data in the byte buffer

Returns:

true if the buffer contains a H264 key frame at offset offset.

getMatchingOutputFormats

protected javax.media.Format[] getMatchingOutputFormats(javax.media.Format inputFormat)

Gets the Formats which are supported by this Codec as output when the input is in a specific Format. Makes sure that the format parameters of a ParameterizedVideoFormat input which are of no concern to this DePacketizer get passed on through the output to the next Codec in the codec chain (i.e. JNIDecoder).

Overrides:

getMatchingOutputFormats in class AbstractCodec2

Parameters:

inputFormat - the Format of the input for which the supported output Formats are to be returned

Returns:

an array of Formats supported by this Codec as output when the input is in the specified inputFormat

requestKeyFrame

public boolean requestKeyFrame(boolean urgent)

Requests a key frame from the remote peer associated with this DePacketizer using the logic of DePacketizer.

Parameters:

urgent - true if the caller has determined that the need for a key frame is urgent and should not obey all constraints with respect to time between two subsequent requests for key frames

Returns:

true if a key frame was indeed requested in response to the call; otherwise, false

setKeyFrameControl

public void setKeyFrameControl(KeyFrameControl keyFrameControl)

Sets the KeyFrameControl to be used by this DePacketizer as a means of control over its key frame-related logic.

Parameters:

keyFrameControl - the KeyFrameControl to be used by this DePacketizer as a means of control over its key frame-related logic