Manages a display thread for rendering buffers and reporting callbacks. More...

#include <PvDisplayThread.h>

Public Member Functions
	PvDisplayThread ()
	Constructor.

virtual	~PvDisplayThread ()
	Destructor.

PvResult	Start (PvPipeline aPipeline, PvGenParameterArray aParameters)
	Starts the display thread using the provided pipeline and parameters. More...

PvResult	Stop (bool aWait)
	Stops the display thread. More...

PvResult	WaitComplete ()
	Waits for the display thread to finish stopping. More...

bool	IsRunning () const
	Indicates whether the display thread is running. More...

uint32_t	GetPriority () const
	Gets the display thread priority. More...

PvResult	SetPriority (uint32_t aPriority)
	Sets the display thread priority. More...

PvBuffer *	RetrieveLatestBuffer ()
	Retrieves the most recent buffer from the pipeline. More...

void	ReleaseLatestBuffer ()
	Releases the most recent buffer previously retrieved. More...

PvBuffer *	RetrieveCompressedBuffer ()
	Retrieves the most recent compressed buffer. More...

void	ReleaseCompressedBuffer ()
	Releases the most recent compressed buffer previously retrieved. More...

bool	GetKeepPartialImagesEnabled () const
	Gets whether partial images are kept instead of dropped. More...

void	SetKeepPartialImagesEnabled (bool aEnabled)
	Enables or disables keeping partial images. More...

bool	GetBufferLogErrorEnabled () const
	Gets whether buffer error logging is enabled. More...

void	SetBufferLogErrorEnabled (bool aValue)
	Enables or disables buffer error logging. More...

bool	GetBufferLogAllEnabled () const
	Gets whether all buffer logging is enabled. More...

void	SetBufferLogAllEnabled (bool aValue)
	Enables or disables logging for all buffers. More...

bool	GetChunkLogEnabled () const
	Gets whether chunk data logging is enabled. More...

void	SetChunkLogEnabled (bool aValue)
	Enables or disables chunk data logging. More...

PvDeinterlacingType	GetDeinterlacing () const
	Gets the deinterlacing mode. More...

void	SetDeinterlacing (PvDeinterlacingType aValue)
	Sets the deinterlacing mode. More...

uint32_t	GetFPS () const
	Gets the current frames-per-second (FPS). More...

uint32_t	GetTargetFPS () const
	Gets the target frames-per-second (FPS). More...

void	SetTargetFPS (uint32_t aValue)
	Sets the target frames-per-second (FPS). More...

bool	GetVSyncEnabled () const
	Gets whether vertical sync is enabled. More...

void	SetVSyncEnabled (bool aEnabled)
	Enables or disables vertical sync. More...

bool	GetDisplayChunkDataEnabled () const
	Gets whether chunk data is displayed. More...

void	SetDisplayChunkDataEnabled (bool aEnabled)
	Enables or disables chunk data display. More...

PvTapGeometryEnum	GetTapGeometry () const
	Gets the current tap geometry used for display. More...

void	SetTapGeometry (PvTapGeometryEnum aGeometry)
	Sets the tap geometry used for display. More...

void	ResetStatistics ()
	Resets display statistics. More...

virtual PvResult	Save (PvPropertyList &aPropertyList)
	Saves display thread settings to a property list. More...

virtual PvResult	Load (PvPropertyList &aPropertyList)
	Loads display thread settings from a property list. More...

Protected Member Functions
virtual void	OnBufferRetrieved (PvBuffer *aBuffer)
	Override to get a callback when a buffer is retrieved from the pipeline. More...

virtual void	OnBufferDisplay (PvBuffer *aBuffer)
	Override to get a callback when a buffer needs to be displayed. More...

virtual void	OnBufferDone (PvBuffer *aBuffer)
	Override to get a just before a buffers is returned to the pipeline. More...

virtual void	OnBufferLog (const PvString &aLog)
	Override to get a logging events from the display thread. More...

virtual void	OnBufferTextOverlay (const PvString &aText)
	Override to get a callback about a text overlay to be displayed. More...

Detailed Description

Manages a display thread for rendering buffers and reporting callbacks.

Thread taking buffers out of a PvPipeline in order to display them.

Inherit your own display thread from this class and override the virtual protected members to carry own the tasks of the display thread.

This class does not know about the display object. It interacts with your display through OnBufferXXX methods.

Member Function Documentation

◆ GetBufferLogAllEnabled()

bool PvDisplayThread::GetBufferLogAllEnabled ( ) const

Gets whether all buffer logging is enabled.

Gets whether all buffers are logged (invoking the log callback)

Returns: True if enabled.

◆ GetBufferLogErrorEnabled()

bool PvDisplayThread::GetBufferLogErrorEnabled ( ) const

Gets whether buffer error logging is enabled.

Gets whether buffer errors are logged (invoking the log callback)

Returns: True if enabled.

◆ GetChunkLogEnabled()

bool PvDisplayThread::GetChunkLogEnabled ( ) const

Gets whether chunk data logging is enabled.

Gets whether buffer chunks are logged (invoking the log callback)

Returns: True if enabled.

◆ GetDeinterlacing()

PvDeinterlacingType PvDisplayThread::GetDeinterlacing ( ) const

Gets the deinterlacing mode.

Gets the current deinterlacing mode.

Only applicable if displaying an interlaced video stream.

Returns: Current deinterlacing mode.

◆ GetDisplayChunkDataEnabled()

bool PvDisplayThread::GetDisplayChunkDataEnabled ( ) const

Gets whether chunk data is displayed.

Returns true if data chunks should be displayed as a text overlay.

The specialized class must implement the right overloaded method in order to receive text overlay updates from this class.

Returns: True if chunk data is displayed.

◆ GetFPS()

uint32_t PvDisplayThread::GetFPS ( ) const

Gets the current frames-per-second (FPS).

Returns the average, effective frame per second rate.

Returns: Average, effective frame per second rate.

◆ GetKeepPartialImagesEnabled()

bool PvDisplayThread::GetKeepPartialImagesEnabled ( ) const

Gets whether partial images are kept instead of dropped.

Returns true if the display thread will attempt to display partial images.

Returns: True if partial images are kept, false otherwise.; True if the keep partial images option is enabled.

◆ GetPriority()

uint32_t PvDisplayThread::GetPriority ( ) const

Gets the display thread priority.

Returns: The display thread priority.; The priority of the thread

◆ GetTapGeometry()

PvTapGeometryEnum PvDisplayThread::GetTapGeometry ( ) const

Gets the current tap geometry used for display.

Returns the tap geometry the display thread is configured with.

If set to a valid tap geometry, tap reconstruction is performed before displaying the image.

Disabled by default (PvTapGeometryUnknown).

Returns: Active tap geometry for the display thread.

◆ GetTargetFPS()

uint32_t PvDisplayThread::GetTargetFPS ( ) const

Gets the target frames-per-second (FPS).

Returns the targeted frame per second rate.

Returns: Targeted frame per second rate

◆ GetVSyncEnabled()

bool PvDisplayThread::GetVSyncEnabled ( ) const

Gets whether vertical sync is enabled.

Returns true if vertical synchronization flags is set.

Returns: True if VSync is enabled, false otherwise.

The display thread does not use this flag, it only keeps it value so it can be read by specialized classes to request a vertical synchronization when a buffer is displayed.

Returns: Synchronization flag value.

◆ IsRunning()

bool PvDisplayThread::IsRunning ( ) const

Indicates whether the display thread is running.

Returns whether the display thread is running or not.

Returns: True if the display thread is running.

◆ Load()

PvResult PvDisplayThread::Load ( PvPropertyList & aPropertyList )

virtual

Loads display thread settings from a property list.

Restores a display thread options.

Parameters

[in] aPropertyList Property list containing settings to load.

Returns: Result of the operation.

The load works on a best effort basis. Whatever can be restored will be restored.

The order to properties in the aPropertyList is not important.

Defined as virtual. Can override in order to load configuration specific to specialized classes.

Parameters

[in] aPropertyList A list of name/value pairs.

Returns

Includes:

PvResult::Code::OK

◆ OnBufferDisplay()

void PvDisplayThread::OnBufferDisplay ( PvBuffer * aBuffer )

protectedvirtual

Override to get a callback when a buffer needs to be displayed.

Since the display thread does not own the display (the application owning the display thread usually does) this callback is used to ask the application to display a buffer on screen.

Parameters

[in] aBuffer The buffer to display.

◆ OnBufferDone()

void PvDisplayThread::OnBufferDone ( PvBuffer * aBuffer )

protectedvirtual

Override to get a just before a buffers is returned to the pipeline.

Parameters

[in] aBuffer The buffer about to be returned to the pipeline.

◆ OnBufferLog()

void PvDisplayThread::OnBufferLog ( const PvString & aLog )

protectedvirtual

Override to get a logging events from the display thread.

The display thread can be configured to generate various log events. The display thread does not have its own log, it simply calls OnBufferLog. The application must override OnBufferLog and funnel the log entry into its own log.

Parameters

[in] aLog The string to append to a log.

◆ OnBufferRetrieved()

void PvDisplayThread::OnBufferRetrieved ( PvBuffer * aBuffer )

protectedvirtual

Override to get a callback when a buffer is retrieved from the pipeline.

Parameters

[in] aBuffer The buffer retrieved from the pipeline.

◆ OnBufferTextOverlay()

void PvDisplayThread::OnBufferTextOverlay ( const PvString & aText )

protectedvirtual

Override to get a callback about a text overlay to be displayed.

Since the display thread does not own the display (the application owning the display thread usually does) this callback is used to ask the application to display a text overlay.

A text overlay can be expected if chunk display is enabled and the buffers retrieved from PvBuffer data chunks.

Parameters

[in] aText The text overlay to be displayed.

◆ ReleaseCompressedBuffer()

void PvDisplayThread::ReleaseCompressedBuffer ( )

Releases the most recent compressed buffer previously retrieved.

Releases the buffer obtained through RetrieveCompressedBuffer.

◆ ReleaseLatestBuffer()

void PvDisplayThread::ReleaseLatestBuffer ( )

Releases the most recent buffer previously retrieved.

Releases the buffer obtained through RetrieveLatestBuffer.

◆ ResetStatistics()

void PvDisplayThread::ResetStatistics ( )

Resets display statistics.

Resets the statistics of the display thread.

◆ RetrieveCompressedBuffer()

PvBuffer * PvDisplayThread::RetrieveCompressedBuffer ( )

Retrieves the most recent compressed buffer.

Returns a pointer to the latest compressed buffer.

Returns: Pointer to the most recent compressed PvBuffer.

Important: calling this method pretty much blocks the display thread. You need to call ReleaseCompressedBuffer in order to unblock the display thread.

Returns: A pointer to the latest compressed buffer

◆ RetrieveLatestBuffer()

PvBuffer * PvDisplayThread::RetrieveLatestBuffer ( )

Retrieves the most recent buffer from the pipeline.

Returns a pointer to the latest retrieved buffer.

Returns: Pointer to the most recent PvBuffer.

Important: calling this method pretty much blocks the display thread. You need to call ReleaseLatestBuffer in order to unblock the display thread.

Returns: A pointer to the latest retrieved buffer

◆ Save()

PvResult PvDisplayThread::Save ( PvPropertyList & aPropertyList )

virtual

Saves display thread settings to a property list.

Persists the current display thread configuration.

Parameters

[out] aPropertyList Property list to receive current settings.

Returns: Result of the operation.

This call builds a list of properties containing pairs of names/values.

Defined as virtual. Can override in order to save configuration specific to specialized classes. Call the base implementation first.

Parameters

[in] aPropertyList A list of pairs of names/values.

Returns

Includes:

PvResult::Code::OK

◆ SetBufferLogAllEnabled()

void PvDisplayThread::SetBufferLogAllEnabled ( bool aValue )

Enables or disables logging for all buffers.

Sets whether all buffers are logged or not.

Parameters

[in]	aValue	True to log all buffers, false to disable.
	aValue	[in] True if enabled.

◆ SetBufferLogErrorEnabled()

void PvDisplayThread::SetBufferLogErrorEnabled ( bool aValue )

Enables or disables buffer error logging.

Sets whether buffer errors are logged or not.

Parameters

[in]	aValue	True to log buffer errors, false to disable.
	aValue	[in] True if enabled.

◆ SetChunkLogEnabled()

void PvDisplayThread::SetChunkLogEnabled ( bool aValue )

Enables or disables chunk data logging.

Sets whether buffer chunks are logged or not.

Parameters

[in]	aValue	True to enable chunk logging, false to disable.
	aValue	[in] True if enabled.

◆ SetDeinterlacing()

void PvDisplayThread::SetDeinterlacing ( PvDeinterlacingType aValue )

Sets the deinterlacing mode.

Parameters

[in] aValue Deinterlacing mode to apply.

Only applicable if display an interlaced video stream.

Parameters

[in] aValue Deinterlacing mdoe.

◆ SetDisplayChunkDataEnabled()

void PvDisplayThread::SetDisplayChunkDataEnabled ( bool aEnabled )

Enables or disables chunk data display.

Sets if the data chunks should be displayed as a text overlay.

Parameters

[in] aEnabled True to display chunk data, false otherwise.

The specialized class must implement the right overloaded method in order to receive text overlay updates from this class.

Parameters

aEnabled [in] New display chunk data mode.

◆ SetKeepPartialImagesEnabled()

void PvDisplayThread::SetKeepPartialImagesEnabled ( bool aEnabled )

Enables or disables keeping partial images.

Sets whether or not the display thread will attempt to display partial images.

Parameters

[in]	aEnabled	True to keep partial images, false to drop them.
[in]	aEnabled	True to attempt to display partial images.

◆ SetPriority()

PvResult PvDisplayThread::SetPriority ( uint32_t aPriority )

Sets the display thread priority.

Set the priority of the display thread.

Parameters

[in] aPriority Priority value to assign to the display thread.

Returns: Result of the operation.

See PvDevice::GetHeartbeatThreadPriority

Parameters

[in] aPriority See PvPipeline::SetBufferHandlingThreadPriority for description of the supported values

Returns

Includes:

◆ SetTapGeometry()

void PvDisplayThread::SetTapGeometry ( PvTapGeometryEnum aGeometry )

Sets the tap geometry used for display.

Sets the tap geometry to be used to tap reconstruction.

Parameters

[in]	aGeometry	Tap geometry to use.
[in]	aGeometry	Tap geometry: use PvTapGeometryUnknown to disable.

◆ SetTargetFPS()

void PvDisplayThread::SetTargetFPS ( uint32_t aValue )

Sets the target frames-per-second (FPS).

Sets the targeted frame per second rate.

Parameters

[in]	aValue	Target FPS value.
[in]	aValue	Targeted frame per second rate.

◆ SetVSyncEnabled()

void PvDisplayThread::SetVSyncEnabled ( bool aEnabled )

Enables or disables vertical sync.

Sets vertical synchronization flag.

Parameters

[in] aEnabled True to enable VSync, false to disable.

The display thread does not use this flag, it only keeps it value so it can be read by specialized classes to request a vertical synchronization when a buffer is displayed.

This flag will only have an effect if it is used when the specialized class. Not all display implementations support vertical synchronization.

Parameters

aEnabled [in] New vertical synchronization flag.

◆ Start()

PvResult PvDisplayThread::Start	(	PvPipeline *	aPipeline,
		PvGenParameterArray *	aParameters
	)

Starts the display thread using the provided pipeline and parameters.

Starts the display thread.

Parameters

[in]	aPipeline	Pointer to the PvPipeline to retrieve buffers from.
[in]	aParameters	Pointer to the PvGenParameterArray for configuration.

Returns: Result of the operation.

Parameters

[in]	aPipeline	The pipeline to retrieve the buffers from.
[in]	aParameters	The display thread parameters.

Returns

Includes:

PvResult::Code::OK
PvResult::Code::THREAD_ERROR if the thread cannot be started

◆ Stop()

PvResult PvDisplayThread::Stop ( bool aWait )

Stops the display thread.

Parameters

[in] aWait Indicates whether to wait for the thread to stop.

Returns: Result of the operation.

Parameters

[in] aWait If true, waits until the thread completes. If false, call WaitComplete to wait

Returns

Includes:

PvResult::Code::OK
PvResult::Code::ABORTED if waiting on the thread to terminate fails

◆ WaitComplete()

PvResult PvDisplayThread::WaitComplete ( )

Waits for the display thread to finish stopping.

Stops the display thread.

Returns

Result of the operation.

Includes:

PvResult::Code::OK
PvResult::Code::ABORTED if waiting on the thread to terminate fails

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

PvDisplayThread.h
PvDisplayThread.cpp

eBUS SDK v7.0.1.7536 API

Public Member Functions

Protected Member Functions

Detailed Description

Member Function Documentation

◆ GetBufferLogAllEnabled()

◆ GetBufferLogErrorEnabled()

◆ GetChunkLogEnabled()

◆ GetDeinterlacing()

◆ GetDisplayChunkDataEnabled()

◆ GetFPS()

◆ GetKeepPartialImagesEnabled()

◆ GetPriority()

◆ GetTapGeometry()

◆ GetTargetFPS()

◆ GetVSyncEnabled()

◆ IsRunning()

◆ Load()

◆ OnBufferDisplay()

◆ OnBufferDone()

◆ OnBufferLog()

◆ OnBufferRetrieved()

◆ OnBufferTextOverlay()

◆ ReleaseCompressedBuffer()

◆ ReleaseLatestBuffer()

◆ ResetStatistics()

◆ RetrieveCompressedBuffer()

◆ RetrieveLatestBuffer()

◆ Save()

◆ SetBufferLogAllEnabled()

◆ SetBufferLogErrorEnabled()

◆ SetChunkLogEnabled()

◆ SetDeinterlacing()

◆ SetDisplayChunkDataEnabled()

◆ SetKeepPartialImagesEnabled()

◆ SetPriority()

◆ SetTapGeometry()

◆ SetTargetFPS()

◆ SetVSyncEnabled()

◆ Start()

◆ Stop()

◆ WaitComplete()