VoiceCallEngine Class Reference

Network-related logic for handling voice channel between nodes. More...

#include <voicecallengine.h>

Inheritance diagram for VoiceCallEngine:

Collaboration diagram for VoiceCallEngine:

Classes
class	VoiceCallExtension

Public Slots
void	nodeConnectionAttemptStatus (Connection::ConnectionState aStatus, const Hash aHashOfAttemptedNode)
void	audioFrameEncoded (quint32 aCallId, quint32 aSeqNo, const QByteArray &aEncodedVoice, Hash aForNode)
void	frameReady (quint32 aCallId, quint32 aSeqNo, const QByteArray &aRawAudio, Hash aForNode)
void	processCallData ()
void	setInputLevel (float aInputLevel)
void	setOutputLevel (float aOutputLevel)

Signals
void	error (QTcpSocket::SocketError socketError)
void	callStateChanged (quint32 aCallId, VoiceCallEngine::CallState aState)
void	startProcessCallData ()
void	inputLevel (float aInputLevel)
void	outputLevel (float aOutputLevel)

Public Member Functions
	VoiceCallEngine (MController &aController, Model &aModel)
	~VoiceCallEngine ()
virtual void	installObserver (MCallStatusObserver *aObserver)
virtual void	removeObserver (MCallStatusObserver *aObserver)
virtual void	insertCallData (quint32 aCallId, quint32 aSeqNo, PayloadType aPayloadType, const QByteArray &aPayload, Hash &aSendingNode)
virtual void	insertCallStatusData (const VoiceCall &aCallStatus, const Hash &aSendingNode)
virtual QList< quint32 >	onGoingCalls () const
virtual CallState	callStatus (quint32 aCallId) const
virtual void	closeCall (quint32 aCallId)
virtual void	acceptCall (quint32 aCallId)
QString	excuseForCallCreation (const Hash &aOperator, const Hash &aNode=KNullHash) const
virtual int	rowCount (const QModelIndex &parent=QModelIndex()) const
virtual int	columnCount (const QModelIndex &parent=QModelIndex()) const
virtual QVariant	data (const QModelIndex &index, int role=Qt::DisplayRole) const
virtual QVariant	headerData (int section, Qt::Orientation orientation, int role=Qt::DisplayRole) const

Private Member Functions
bool	setupNewOutgoingCall (VoiceCallExtension &aCall)
bool	setupNewIncomingCall (VoiceCallExtension &aCall)
void	sendCallStatusUpdates (quint32 aCallId, CallState aState)
Hash	callPeerFingerPrint (const VoiceCall &aCall) const
void	removeCallFromArray (VoiceCallExtension &aCall)
void	addCallToArray (VoiceCallExtension &aCall)
void	sendCallStatusUpdateToRemote (const VoiceCall &aCall, bool aDoSign=true)
QString	callStatusString (const VoiceCallExtension &aCall) const
bool	checkForNodeValidity (const VoiceCall &aCallStatus, const Hash &aSendingNode) const
bool	setupLocalAudioCapture (VoiceCallExtension &aCall)
bool	setupAudioOutput (VoiceCallExtension &aCall)
bool	addCallToMixer (const VoiceCallExtension &aCall)
bool	removeCallFromMixer (const VoiceCallExtension &aCall)

Private Attributes
MController &	iController
Model &	iModel
QList< MCallStatusObserver * >	iCallObservers
QList< VoiceCallExtension >	iOnGoingCalls
AudioMixer *	iMixer
AudioSource *	iAudioSource
AudioPlayer *	iAudioPlayer
QList< QPair< VoiceCall, Hash > >	iCallDataPendingProcessing

Additional Inherited Members
Public Types inherited from MVoiceCallEngine
enum	CallState {   Initial, Incoming, Open, Closing,   Closed, Error, NoCall }
enum	PayloadType { Audio =1, Control =2 }

Detailed Description

Network-related logic for handling voice channel between nodes.

"Voice call" is a bit different from persisted content handling: It happens between, nodes, not between operators. It has realtime- requirements and does not directly store anything on data storage.

This class contains networking-related logic and audio stream handling. Separate UI must be built on top of this. This inherits QAbstractTableModel to provide easy access for UI-components to calldata.

For actual call data handling see AudioMixer and other classes in the same directory.

Constructor & Destructor Documentation

VoiceCallEngine()

VoiceCallEngine::VoiceCallEngine	(	MController &	aController,
		Model &	aModel
	)

Constructor

Parameters

aController	application controller. not owned
aModel	persistent storage.

~VoiceCallEngine()

VoiceCallEngine::~VoiceCallEngine

(

)

Destructor

Member Function Documentation

acceptCall()

virtual void VoiceCallEngine::acceptCall ( quint32  aCallId )

virtual

Method called as result UI-action. This accepts an incoming call.

Implements MVoiceCallEngine.

addCallToArray()

void VoiceCallEngine::addCallToArray ( VoiceCallExtension &  aCall )

private

addCallToMixer()

bool VoiceCallEngine::addCallToMixer ( const VoiceCallExtension &  aCall )

private

method for conditioanally adding voice streams to mixer module

audioFrameEncoded

void VoiceCallEngine::audioFrameEncoded ( quint32  aCallId, quint32  aSeqNo, const QByteArray &  aEncodedVoice, Hash  aForNode  )

slot

Voice data captured from microphone and mixed with other possible streams is delivered to over-the-network recipients using this slot. In practice input into this method comes from audio encoder and this method is responsible for distributing the encoded audio frame to all call participants.

callPeerFingerPrint()

Hash VoiceCallEngine::callPeerFingerPrint ( const VoiceCall &  aCall ) const

private

Method that returns the call peer node address: either destination or originating.

callStateChanged

void VoiceCallEngine::callStateChanged ( quint32  aCallId, VoiceCallEngine::CallState  aState  )

signal

Signal for communicating call state changes

callStatus()

virtual CallState VoiceCallEngine::callStatus ( quint32  aCallId ) const

virtual

method for getting status of a call

Implements MVoiceCallEngine.

callStatusString()

QString VoiceCallEngine::callStatusString ( const VoiceCallExtension &  aCall ) const

private

checkForNodeValidity()

bool VoiceCallEngine::checkForNodeValidity ( const VoiceCall &  aCallStatus, const Hash &  aSendingNode  ) const

private

Method that checks that aCallStatus can be from aSendingNode

closeCall()

virtual void VoiceCallEngine::closeCall ( quint32  aCallId )

virtual

Method called as result UI-action. This terminates ongoing call.

Implements MVoiceCallEngine.

columnCount()

virtual int VoiceCallEngine::columnCount ( const QModelIndex &  parent = QModelIndex() ) const

virtual

re-implemented from QAbstractTableModel

Returns

number of columns in view

data()

virtual QVariant VoiceCallEngine::data ( const QModelIndex &  index, int  role = Qt::DisplayRole  ) const

virtual

re-implemented from QAbstractListModel

Returns

data to display in list of ongoing calls

error

void VoiceCallEngine::error ( QTcpSocket::SocketError  socketError )

signal

excuseForCallCreation()

QString VoiceCallEngine::excuseForCallCreation	(	const Hash &	aOperator,
		const Hash &	aNode = KNullHash
	)		const

Method for querying for an excuse why a call can (not) be made to particular operator or node

Parameters

aOperator	identifier of operator whose call-creation status is queried.
aNode	node of the operator, if known

Returns

String telling if voice call can be made

frameReady

void VoiceCallEngine::frameReady ( quint32  aCallId, quint32  aSeqNo, const QByteArray &  aRawAudio, Hash  aForNode  )

slot

This slot is called when mixer when audio frame is ready to be sent. In practice audio mixer emits a singal to this slot once for each node that is connected to same call.

Parameters

aCallId	is identifier of the call where this frame belongs to
aSeqNo	sequence number of packets in stream
aRawAudio	is non-encoded audio frame, as array of floats
aForNode	specifies the node that will receive this particular audio frame.

headerData()

virtual QVariant VoiceCallEngine::headerData ( int  section, Qt::Orientation  orientation, int  role = Qt::DisplayRole  ) const

virtual

re-implemented from QAbstractListModel

Returns

strings for headers of the call list UI

inputLevel

void VoiceCallEngine::inputLevel ( float  aInputLevel )

signal

signal for communicating audio input (microphone) level

insertCallData()

virtual void VoiceCallEngine::insertCallData ( quint32  aCallId, quint32  aSeqNo, PayloadType  aPayloadType, const QByteArray &  aPayload, Hash &  aSendingNode  )

virtual

Method for reception of call real-time data. This is called from network-parts that receive the data packet over some protocol and then feed it here to make it heard.

Called from protocol parser. Parser does not lock datamodel prior to call.

Parameters

aCallId	is call ( stream ) identifier
aSeqNo	is sequence number of rt data in stream
aPayloadType	tells what kind of payload it is
aPayload	actual bytes
aSendingNode	node what sent the data package

Implements MVoiceCallEngine.

insertCallStatusData()

virtual void VoiceCallEngine::insertCallStatusData ( const VoiceCall &  aCallStatus, const Hash &  aSendingNode  )

virtual

Method for reception of call status data. This is called from network-parts that receive the data packet over some protocol and then feed it here to move the call engine to some direction

Note that the call data inserted via this method may be call that this node originally made and at the receiving end this same method is used to inject the new incoming call into the engine.

Another note to take into consideration is the handling if node-data in aCallStatus. Call status is passed as reference so the ownership of the call data object instance is not tranferred into voice call engine. Inside call data there are 2 pointers to originating and destination nodes. Ownership of content of those pointers is not tranferred either. VoiceCallEngine will make local copies (if it sees that necessary) of the node-pointer contents and caller of this method will be responsible for deleting the node-objects in call-data if they were created only for the purpose of making a voice call.

DataModel.lock() should be called before calling this method

Parameters

aCallStatus	contains information about a call.
aSendingNode	is fingerprint of the node where the DTO is coming from. May be local node also.

Implements MVoiceCallEngine.

installObserver()

virtual void VoiceCallEngine::installObserver ( MCallStatusObserver *  aObserver )

virtual

Method for installing call state observer

Implements MVoiceCallEngine.

nodeConnectionAttemptStatus

void VoiceCallEngine::nodeConnectionAttemptStatus ( Connection::ConnectionState  aStatus, const Hash  aHashOfAttemptedNode  )

slot

This signal is about node-connection status and closed connections will be communicated using this same signal:

onGoingCalls()

virtual QList<quint32> VoiceCallEngine::onGoingCalls ( ) const

virtual

method for getting identifiers of ongoing calls

Implements MVoiceCallEngine.

outputLevel

void VoiceCallEngine::outputLevel ( float  aOutputLevel )

signal

signal for communicating audio output (spekar) level

processCallData

void VoiceCallEngine::processCallData ( )

slot

slot that is called for call status data processing. reason for this slot is that we want to process status data in UI thread because we create QObjects there and want to delete them also in same thread, this easier to handle in Qt this way.

In practice, the call data is put into iCallDataPendingProcessing and this slot is called in queued manner

removeCallFromArray()

void VoiceCallEngine::removeCallFromArray ( VoiceCallExtension &  aCall )

private

removeCallFromMixer()

bool VoiceCallEngine::removeCallFromMixer ( const VoiceCallExtension &  aCall )

private

method for conditioanally removing voice streams from mixer module

removeObserver()

virtual void VoiceCallEngine::removeObserver ( MCallStatusObserver *  aObserver )

virtual

Method for removing call state observer

Implements MVoiceCallEngine.

rowCount()

virtual int VoiceCallEngine::rowCount ( const QModelIndex &  parent = QModelIndex() ) const

virtual

Methods inherited from QAbstractTableModel: rowCount

Returns

number of ongoing calls

sendCallStatusUpdates()

void VoiceCallEngine::sendCallStatusUpdates ( quint32  aCallId, CallState  aState  )

private

call status gossip method

sendCallStatusUpdateToRemote()

void VoiceCallEngine::sendCallStatusUpdateToRemote ( const VoiceCall &  aCall, bool  aDoSign = true  )

private

setInputLevel

void VoiceCallEngine::setInputLevel ( float  aInputLevel )

slot

slot for setting audio input (microphone) level

setOutputLevel

void VoiceCallEngine::setOutputLevel ( float  aOutputLevel )

slot

slot for setting audio output (spekar) level

setupAudioOutput()

bool VoiceCallEngine::setupAudioOutput ( VoiceCallExtension &  aCall )

private

Method for setting up local audio output. If call has VoiceCall::iOkToProceed set to false, then output will be torn down.

setupLocalAudioCapture()

bool VoiceCallEngine::setupLocalAudioCapture ( VoiceCallExtension &  aCall )

private

Method for setting up local audio capture. If call has VoiceCall::iOkToProceed set to false, then capture will be torn down.

setupNewIncomingCall()

bool VoiceCallEngine::setupNewIncomingCall ( VoiceCallExtension &  aCall )

private

Called when a new call is initiated from remote node

setupNewOutgoingCall()

bool VoiceCallEngine::setupNewOutgoingCall ( VoiceCallExtension &  aCall )

private

Called when a new call is initiated from local node

startProcessCallData

void VoiceCallEngine::startProcessCallData ( )

signal

signal for starting processCallData

Member Data Documentation

iAudioPlayer

AudioPlayer* VoiceCallEngine::iAudioPlayer

private

iAudioSource

AudioSource* VoiceCallEngine::iAudioSource

private

iCallDataPendingProcessing

QList<QPair<VoiceCall, Hash> > VoiceCallEngine::iCallDataPendingProcessing

private

iCallObservers

QList<MCallStatusObserver*> VoiceCallEngine::iCallObservers

private

iController

MController& VoiceCallEngine::iController

private

application controller

iMixer

AudioMixer* VoiceCallEngine::iMixer

private

Exactly one audio mixer: has list of streams to mix. Idea is that list of mixed streams does not need to be same as list of ongoing calls. At least the local microphone input is additional stream

iModel

Model& VoiceCallEngine::iModel

private

persistent storage

iOnGoingCalls

QList<VoiceCallExtension> VoiceCallEngine::iOnGoingCalls

private

data about calls currently handled

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The documentation for this class was generated from the following file:

• voicecallengine.h