vtkDataEncoder Class Reference

class used to compress/encode images using threads. More...

#include <vtkDataEncoder.h>

Inheritance diagram for vtkDataEncoder:

Collaboration diagram for vtkDataEncoder:

Public Types
typedef vtkObject	Superclass

Public Member Functions
virtual vtkTypeBool	IsA (const char *type)
	Return 1 if this class is the same type of (or a subclass of) the named class.
vtkDataEncoder *	NewInstance () const
void	PrintSelf (ostream &os, vtkIndent indent) override
	Methods invoked by print to print information about the object including superclasses.
void	Initialize ()
	Re-initializes the encoder.
void	PushAndTakeReference (vtkTypeUInt32 key, vtkImageData *&data, int quality, int encoding=1)
	Push an image into the encoder.
void	Push (vtkTypeUInt32 key, vtkImageData *data, int quality, int encoding=1)
	Push an image into the encoder.
bool	GetLatestOutput (vtkTypeUInt32 key, vtkSmartPointer< vtkUnsignedCharArray > &data)
	Get access to the most-recent fully encoded result corresponding to the given key, if any.
void	Flush (vtkTypeUInt32 key)
	Flushes the encoding pipe and blocks till the most recently pushed image for the particular key has been processed.
const char *	EncodeAsBase64Png (vtkImageData *img, int compressionLevel=5)
	Take an image data and synchronously convert it to a base-64 encoded png.
const char *	EncodeAsBase64Jpg (vtkImageData *img, int quality=50)
	Take an image data and synchronously convert it to a base-64 encoded jpg.
void	Finalize ()
	This method will wait for any running thread to terminate.
void	SetMaxThreads (vtkTypeUInt32)
	Define the number of worker threads to use.
virtual vtkTypeUInt32	GetMaxThreads ()
	Define the number of worker threads to use.
Public Member Functions inherited from vtkObject
	vtkBaseTypeMacro (vtkObject, vtkObjectBase)
virtual void	DebugOn ()
	Turn debugging output on.
virtual void	DebugOff ()
	Turn debugging output off.
bool	GetDebug ()
	Get the value of the debug flag.
void	SetDebug (bool debugFlag)
	Set the value of the debug flag.
virtual void	Modified ()
	Update the modification time for this object.
virtual vtkMTimeType	GetMTime ()
	Return this object's modified time.
void	PrintSelf (ostream &os, vtkIndent indent) override
	Methods invoked by print to print information about the object including superclasses.
void	RemoveObserver (unsigned long tag)
void	RemoveObservers (unsigned long event)
void	RemoveObservers (const char *event)
void	RemoveAllObservers ()
vtkTypeBool	HasObserver (unsigned long event)
vtkTypeBool	HasObserver (const char *event)
int	InvokeEvent (unsigned long event)
int	InvokeEvent (const char *event)
unsigned long	AddObserver (unsigned long event, vtkCommand *, float priority=0.0f)
	Allow people to add/remove/invoke observers (callbacks) to any VTK object.
unsigned long	AddObserver (const char *event, vtkCommand *, float priority=0.0f)
	Allow people to add/remove/invoke observers (callbacks) to any VTK object.
vtkCommand *	GetCommand (unsigned long tag)
	Allow people to add/remove/invoke observers (callbacks) to any VTK object.
void	RemoveObserver (vtkCommand *)
	Allow people to add/remove/invoke observers (callbacks) to any VTK object.
void	RemoveObservers (unsigned long event, vtkCommand *)
	Allow people to add/remove/invoke observers (callbacks) to any VTK object.
void	RemoveObservers (const char *event, vtkCommand *)
	Allow people to add/remove/invoke observers (callbacks) to any VTK object.
vtkTypeBool	HasObserver (unsigned long event, vtkCommand *)
	Allow people to add/remove/invoke observers (callbacks) to any VTK object.
vtkTypeBool	HasObserver (const char *event, vtkCommand *)
	Allow people to add/remove/invoke observers (callbacks) to any VTK object.
template<class U , class T >
unsigned long	AddObserver (unsigned long event, U observer, void(T::*callback)(), float priority=0.0f)
	Overloads to AddObserver that allow developers to add class member functions as callbacks for events.
template<class U , class T >
unsigned long	AddObserver (unsigned long event, U observer, void(T::*callback)(vtkObject *, unsigned long, void *), float priority=0.0f)
	Overloads to AddObserver that allow developers to add class member functions as callbacks for events.
template<class U , class T >
unsigned long	AddObserver (unsigned long event, U observer, bool(T::*callback)(vtkObject *, unsigned long, void *), float priority=0.0f)
	Allow user to set the AbortFlagOn() with the return value of the callback method.
int	InvokeEvent (unsigned long event, void *callData)
	This method invokes an event and return whether the event was aborted or not.
int	InvokeEvent (const char *event, void *callData)
	This method invokes an event and return whether the event was aborted or not.
Public Member Functions inherited from vtkObjectBase
const char *	GetClassName () const
	Return the class name as a string.
virtual vtkTypeBool	IsA (const char *name)
	Return 1 if this class is the same type of (or a subclass of) the named class.
virtual vtkIdType	GetNumberOfGenerationsFromBase (const char *name)
	Given the name of a base class of this class type, return the distance of inheritance between this class type and the named class (how many generations of inheritance are there between this class and the named class).
virtual void	Delete ()
	Delete a VTK object.
virtual void	FastDelete ()
	Delete a reference to this object.
void	InitializeObjectBase ()
void	Print (ostream &os)
	Print an object to an ostream.
virtual void	Register (vtkObjectBase *o)
	Increase the reference count (mark as used by another object).
virtual void	UnRegister (vtkObjectBase *o)
	Decrease the reference count (release by another object).
int	GetReferenceCount ()
	Return the current reference count of this object.
void	SetReferenceCount (int)
	Sets the reference count.
bool	GetIsInMemkind () const
	A local state flag that remembers whether this object lives in the normal or extended memory space.
virtual void	PrintHeader (ostream &os, vtkIndent indent)
	Methods invoked by print to print information about the object including superclasses.
virtual void	PrintTrailer (ostream &os, vtkIndent indent)
	Methods invoked by print to print information about the object including superclasses.

Static Public Member Functions
static vtkDataEncoder *	New ()
static vtkTypeBool	IsTypeOf (const char *type)
static vtkDataEncoder *	SafeDownCast (vtkObjectBase *o)
Static Public Member Functions inherited from vtkObject
static vtkObject *	New ()
	Create an object with Debug turned off, modified time initialized to zero, and reference counting on.
static void	BreakOnError ()
	This method is called when vtkErrorMacro executes.
static void	SetGlobalWarningDisplay (int val)
	This is a global flag that controls whether any debug, warning or error messages are displayed.
static void	GlobalWarningDisplayOn ()
	This is a global flag that controls whether any debug, warning or error messages are displayed.
static void	GlobalWarningDisplayOff ()
	This is a global flag that controls whether any debug, warning or error messages are displayed.
static int	GetGlobalWarningDisplay ()
	This is a global flag that controls whether any debug, warning or error messages are displayed.
Static Public Member Functions inherited from vtkObjectBase
static vtkTypeBool	IsTypeOf (const char *name)
	Return 1 if this class type is the same type of (or a subclass of) the named class.
static vtkIdType	GetNumberOfGenerationsFromBaseType (const char *name)
	Given a the name of a base class of this class type, return the distance of inheritance between this class type and the named class (how many generations of inheritance are there between this class and the named class).
static vtkObjectBase *	New ()
	Create an object with Debug turned off, modified time initialized to zero, and reference counting on.
static void	SetMemkindDirectory (const char *directoryname)
	The name of a directory, ideally mounted -o dax, to memory map an extended memory space within.
static bool	GetUsingMemkind ()
	A global state flag that controls whether vtkObjects are constructed in the usual way (the default) or within the extended memory space.

Protected Member Functions
virtual vtkObjectBase *	NewInstanceInternal () const
	vtkDataEncoder ()
	~vtkDataEncoder () override
Protected Member Functions inherited from vtkObject
	vtkObject ()
	~vtkObject () override
void	RegisterInternal (vtkObjectBase *, vtkTypeBool check) override
void	UnRegisterInternal (vtkObjectBase *, vtkTypeBool check) override
void	InternalGrabFocus (vtkCommand *mouseEvents, vtkCommand *keypressEvents=nullptr)
	These methods allow a command to exclusively grab all events.
void	InternalReleaseFocus ()
	These methods allow a command to exclusively grab all events.
Protected Member Functions inherited from vtkObjectBase
	vtkObjectBase ()
virtual	~vtkObjectBase ()
virtual void	RegisterInternal (vtkObjectBase *, vtkTypeBool check)
virtual void	UnRegisterInternal (vtkObjectBase *, vtkTypeBool check)
virtual void	ReportReferences (vtkGarbageCollector *)
	vtkObjectBase (const vtkObjectBase &)
void	operator= (const vtkObjectBase &)

Protected Attributes
vtkTypeUInt32	MaxThreads
Protected Attributes inherited from vtkObject
bool	Debug
vtkTimeStamp	MTime
vtkSubjectHelper *	SubjectHelper
Protected Attributes inherited from vtkObjectBase
std::atomic< int32_t >	ReferenceCount
vtkWeakPointerBase **	WeakPointers

Additional Inherited Members
Static Protected Member Functions inherited from vtkObjectBase
static vtkMallocingFunction	GetCurrentMallocFunction ()
static vtkReallocingFunction	GetCurrentReallocFunction ()
static vtkFreeingFunction	GetCurrentFreeFunction ()
static vtkFreeingFunction	GetAlternateFreeFunction ()

Detailed Description

class used to compress/encode images using threads.

vtkDataEncoder is used to compress and encode images using threads. Multiple images can be pushed into the encoder for compression and encoding. We use a vtkTypeUInt32 as the key to identify different image pipes. The images in each pipe will be processed in parallel threads. The latest compressed and encoded image can be accessed using GetLatestOutput().

vtkDataEncoder uses a thread-pool to do the compression and encoding in parallel. Note that images may not come out of the vtkDataEncoder in the same order as they are pushed in, if an image pushed in at N-th location takes longer to compress and encode than that pushed in at N+1-th location or if it was pushed in before the N-th location was even taken up for encoding by the a thread in the thread pool.

Definition at line 45 of file vtkDataEncoder.h.

Member Typedef Documentation

Superclass

typedef vtkObject vtkDataEncoder::Superclass

Definition at line 49 of file vtkDataEncoder.h.

Constructor & Destructor Documentation

vtkDataEncoder()

vtkDataEncoder::vtkDataEncoder ( )

protected

~vtkDataEncoder()

vtkDataEncoder::~vtkDataEncoder ( )

overrideprotected

Member Function Documentation

New()

static vtkDataEncoder * vtkDataEncoder::New ( )

static

IsTypeOf()

static vtkTypeBool vtkDataEncoder::IsTypeOf ( const char *  type )

static

IsA()

virtual vtkTypeBool vtkDataEncoder::IsA ( const char *  name )

virtual

Return 1 if this class is the same type of (or a subclass of) the named class.

Returns 0 otherwise. This method works in combination with vtkTypeMacro found in vtkSetGet.h.

Reimplemented from vtkObjectBase.

SafeDownCast()

static vtkDataEncoder * vtkDataEncoder::SafeDownCast ( vtkObjectBase *  o )

static

NewInstanceInternal()

virtual vtkObjectBase * vtkDataEncoder::NewInstanceInternal ( ) const

protectedvirtual

NewInstance()

vtkDataEncoder * vtkDataEncoder::NewInstance

(

)

const

PrintSelf()

void vtkDataEncoder::PrintSelf ( ostream &  os, vtkIndent  indent  )

overridevirtual

Methods invoked by print to print information about the object including superclasses.

Typically not called by the user (use Print() instead) but used in the hierarchical print process to combine the output of several classes.

Reimplemented from vtkObject.

SetMaxThreads()

void vtkDataEncoder::SetMaxThreads

(

vtkTypeUInt32

)

Define the number of worker threads to use.

Default is 3. Initialize() needs to be called after changing the thread count.

GetMaxThreads()

virtual vtkTypeUInt32 vtkDataEncoder::GetMaxThreads ( )

virtual

Define the number of worker threads to use.

Default is 3. Initialize() needs to be called after changing the thread count.

Initialize()

void vtkDataEncoder::Initialize

(

)

Re-initializes the encoder.

This will abort any on going encoding threads and clear internal data-structures.

PushAndTakeReference()

void vtkDataEncoder::PushAndTakeReference	(	vtkTypeUInt32	key,
		vtkImageData *&	data,
		int	quality,
		int	encoding = 1
	)

Push an image into the encoder.

It is not safe to modify the image after this point, including changing the reference counts for it. You may run into thread safety issues. Typically, the caller code will simply release reference to the data and stop using it. vtkDataEncoder takes over the reference for the image and will call vtkObject::UnRegister() on it when it's done. encoding can be set to 0 to skip encoding.

Push()

void vtkDataEncoder::Push	(	vtkTypeUInt32	key,
		vtkImageData *	data,
		int	quality,
		int	encoding = 1
	)

Push an image into the encoder.

The data is considered unchanging and thus should not be modified once pushed. Reference count changes are now thread safe and hence callers should ensure they release the reference held, if appropriate.

GetLatestOutput()

bool vtkDataEncoder::GetLatestOutput	(	vtkTypeUInt32	key,
		vtkSmartPointer< vtkUnsignedCharArray > &	data
	)

Get access to the most-recent fully encoded result corresponding to the given key, if any.

This methods returns true if the data obtained is the result from the most recent Push() for the key, if any. If this method returns false, it means that there's some image either being processed on pending processing.

Flush()

void vtkDataEncoder::Flush

(

vtkTypeUInt32

key

)

Flushes the encoding pipe and blocks till the most recently pushed image for the particular key has been processed.

This call will block. Once this method returns, caller can use GetLatestOutput(key) to access the processed output.

EncodeAsBase64Png()

const char * vtkDataEncoder::EncodeAsBase64Png	(	vtkImageData *	img,
		int	compressionLevel = 5
	)

Take an image data and synchronously convert it to a base-64 encoded png.

EncodeAsBase64Jpg()

const char * vtkDataEncoder::EncodeAsBase64Jpg	(	vtkImageData *	img,
		int	quality = 50
	)

Take an image data and synchronously convert it to a base-64 encoded jpg.

Finalize()

void vtkDataEncoder::Finalize

(

)

This method will wait for any running thread to terminate.

Member Data Documentation

MaxThreads

vtkTypeUInt32 vtkDataEncoder::MaxThreads

protected

Definition at line 123 of file vtkDataEncoder.h.

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

• Web/Core/vtkDataEncoder.h