Class for the canny edge detector. More...

#include <CannyOp.h>

Inheritance diagram for icl::filter::CannyOp:

Public Member Functions
	CannyOp (icl32f lowThresh=0, icl32f highThresh=255, int preBlurRadius=0)
	Constructor. More...

	CannyOp (UnaryOp dxOp, UnaryOp dyOp, icl32f lowThresh=0, icl32f highThresh=255, bool deleteOps=true, int preBlurRadius=0)
	Constructor. More...

virtual	~CannyOp ()
	Destructor. More...

void	setThresholds (icl32f lowThresh, icl32f highThresh)
	changes the Thresholds More...

icl32f	getLowThreshold () const
	returns the lower threshold More...

icl32f	getHighThreshold () const
	returns the upper threshold More...

virtual void	apply (const core::ImgBase src, core::ImgBase *dst)
	applies the Canny Operator More...

virtual void	apply (const core::ImgBase src_x, const core::ImgBase src_y, core::ImgBase **dst)
	applies the Canny Operator More...

void	setPreBlurRadius (int preBlurRadius)
	sets the pre-blur-radius More...

void	setUseDerivativesInfo (bool use_derivatives)

bool	getPreBlurRadius () const
	returns current pre-blur feature state More...

virtual void	apply (const core::ImgBase operand1, core::ImgBase *dst)=0
	Import unaryOps apply function without destination image. More...

virtual const core::ImgBase *	apply (const core::ImgBase *src)
	Import unaryOps apply function without destination image. More...

Public Member Functions inherited from icl::filter::UnaryOp
	UnaryOp ()
	Explicit empty constructor. More...

	UnaryOp (const UnaryOp &other)
	Explicit copy constructor. More...

UnaryOp &	operator= (const UnaryOp &other)
	Explicit declaration of the assignment operator. More...

virtual	~UnaryOp ()
	Destructor. More...

virtual ICL_DEPRECATED void	applyMT (const core::ImgBase operand1, core::ImgBase *dst, unsigned int nThreads)
	apply function for multithreaded filtering (currently even slower than using one thread) More...

virtual const core::ImgBase *	apply (const core::ImgBase *src)
	applys the filter usign an internal buffer as output image More...

void	operator() (const core::ImgBase src, core::ImgBase *dst)
	function operator (alternative for apply(src,dst) More...

const core::ImgBase *	operator() (const core::ImgBase *src)
	function operator for the implicit destination apply(src) call More...

const core::ImgBase &	operator() (const core::ImgBase &src)
	reference based function operator More...

void	setClipToROI (bool bClipToROI)
	sets if the image should be clip to ROI or not More...

void	setCheckOnly (bool bCheckOnly)
	sets if the destination image should be adapted to the source, or if it is only checked if it can be adapted. More...

bool	getClipToROI () const
	returns the ClipToROI status More...

bool	getCheckOnly () const
	returns the CheckOnly status More...

virtual void	setPropertyValue (const std::string &propertyName, const utils::Any &value)
	sets value of a property (always call call_callbacks(propertyName) or Configurable::setPropertyValue) More...

Public Member Functions inherited from icl::utils::Configurable
virtual	~Configurable ()
	virtual destructor More...

	Configurable (const Configurable &other)
	Copy constructor. More...

Configurable &	operator= (const Configurable &other)
	Assignment operator. More...

void	setConfigurableID (const std::string &ID)
	sets the ID of this configurable More...

const std::string &	getConfigurableID () const
	returns the configurables static ID More...

bool	isOrderedFlagSet () const
	returns whether the ordered flag is set More...

void	deactivateProperty (const std::string &pattern)
	adds an additional deativation pattern More...

void	deleteDeactivationPattern (const std::string &pattern)
	removed a formerly added deactivation pattern More...

std::vector< std::string >	getPropertyListWithoutDeactivated () const
	this returns a filtered list of properties (using all filters added by deactivateProperty) More...

virtual void	adaptProperty (const std::string &name, const std::string &newType, const std::string &newInfo, const std::string &newToolTip)
	this function can be used to adapt a specific property afterwards More...

void	registerCallback (const Callback &cb)
	add a callback for changed properties More...

void	removedCallback (const Callback &cb)
	removes a callback that was registered before More...

void	syncChangesTo (Configurable *others, int num=1)
	this can be used to let this instance also apply property changes to others More...

virtual std::vector< std::string >	getPropertyList () const
	returns a list of All properties, that can be set using setProperty More...

virtual bool	supportsProperty (const std::string &propertyName) const
	base implementation for property check (seaches in the property list) More...

virtual void	saveProperties (const std::string &filename, const std::vector< std::string > &propertiesToSkip=EMPTY_VEC) const
	writes all available properties into a file More...

virtual void	loadProperties (const std::string &filename, const std::vector< std::string > &propertiesToSkip=EMPTY_VEC)
	reads a camera config file from disc More...

virtual std::string	getPropertyType (const std::string &propertyName) const
	get type of property More...

virtual std::string	getPropertyInfo (const std::string &propertyName) const
	get information of a properties valid values More...

virtual Any	getPropertyValue (const std::string &propertyName) const
	returns the current value of a property or a parameter More...

virtual std::string	getPropertyToolTip (const std::string &propertyName) const
	returns the tooltip description for a given property More...

virtual int	getPropertyVolatileness (const std::string &propertyName) const
	Returns whether this property may be changed internally. More...

Private Member Functions
void	property_callback (const Property &p)

void	setUpPreBlurOp ()

void	applyCanny32f (const core::ImgBase dx, const core::ImgBase dy, core::ImgBase *dst, int c)
	applies canny for one channel More...

void	applyCanny16s (const core::ImgBase dx, const core::ImgBase dy, core::ImgBase *dst, int c)

Private Attributes
std::vector< icl8u >	m_cannyBuf
	buffer for ippiCanny More...

core::ImgBase *	m_derivatives [2]

UnaryOp *	m_ops [2]

UnaryOp *	m_preBlurOp

icl32f	m_lowT

icl32f	m_highT

bool	m_ownOps

bool	m_use_derivatives_info

core::Img32f	m_buffer

int	m_preBlurRadius

Additional Inherited Members
Public Types inherited from icl::utils::Configurable
typedef Function< void, const Property & >	Callback
	Function type for changed properties. More...

Static Public Member Functions inherited from icl::filter::UnaryOp
static UnaryOp *	fromString (const std::string &definition)
	Creates a UnaryOp instance from given string definition. More...

static std::string	getFromStringSyntax (const std::string &opSpecifier)
	gives a string syntax description for given opSpecifier More...

static std::vector< std::string >	listFromStringOps ()
	returns a list of all supported OP_SPEC values for the fromString function More...

static void	applyFromString (const std::string &definition, const core::ImgBase src, core::ImgBase *dst)
	creates, applies and releases a UnaryOp defined by given definition string More...

Static Public Member Functions inherited from icl::utils::Configurable
static std::string	create_default_ID (const std::string &prefix)
	this function can be used in subclasses to create a default ID More...

static Configurable *	get (const std::string &id)
	returns configurable by given ID More...

static void	register_configurable_type (const std::string &classname, Function< Configurable * > creator)
	registers a configurable type More...

static std::vector< std::string >	get_registered_configurables ()
	returns a list of all registered configurable classnames More...

static Configurable *	create_configurable (const std::string &classname)
	creates a configurable by given name More...

Static Public Attributes inherited from icl::utils::Configurable
static const std::vector< std::string >	EMPTY_VEC
	used as shortcut – just an empty vector of std::strings More...

Protected Member Functions inherited from icl::filter::UnaryOp
bool	prepare (core::ImgBase **ppoDst, core::depth eDepth, const utils::Size &imgSize, core::format eFormat, int nChannels, const utils::Rect &roi, utils::Time timestamp=utils::Time::null)

virtual bool	prepare (core::ImgBase *ppoDst, const core::ImgBase poSrc)
	check+adapt destination image to properties of given source image More...

virtual bool	prepare (core::ImgBase *ppoDst, const core::ImgBase poSrc, core::depth eDepth)

Protected Member Functions inherited from icl::utils::Configurable
void	addProperty (const std::string &name, const std::string &type, const std::string &info, const Any &value=Any(), const int volatileness=0, const std::string &tooltip=std::string())
	This can be used by derived classes to store supported properties in the internal list. More...

void	addChildConfigurable (Configurable *configurable, const std::string &childPrefix="")
	This adds another configurable as child. More...

void	removeChildConfigurable (Configurable *configurable)
	removes the given child configurable More...

Property &	prop (const std::string &propertyName)
	this CAN be used e.g. to store a property value in internal property-list More...

const Property &	prop (const std::string &propertyName) const
	this CAN be used e.g. to store a property value in internal property-list More...

	Configurable (const std::string &ID="", bool ordered=true)
	create this configurable with given ID More...

void	call_callbacks (const std::string &propertyName, const Configurable *caller) const
	calls all registered callbacks More...

Protected Member Functions inherited from icl::utils::Uncopyable
	Uncopyable ()
	Empty base constructor. More...

Protected Attributes inherited from icl::filter::UnaryOp
utils::MultiThreader *	m_poMT

Protected Attributes inherited from icl::utils::Configurable
std::vector< Callback >	callbacks
	internally managed list of callbacks More...

Detailed Description

Class for the canny edge detector.

Overview

The canny edge detector detects image borders from gray-scale images. It's result is an Img8u binary image containing thin borders.

Algorithm

The canny edge detector is a very common filter for edge detection, therefore it is already implemented in the IPP. The algorithm can be split into 3 major parts:

Image differentiation here, image x and y gradients are computed. Commonly this is done using sobel- X and -Y filters.
Non-Maximum suppression The image differentiation result is converted into an image intensity map and into a gradient direction map. Now all pixels are suppressed, that are not ridges in gradient intensity map mountain.
Thresholding Here a special threshold operation is used. Two threshold values (l=low threshold and h=high threshold) split the edge intensity scale into 3 parts:
1. below the lower threshold pixels with such values are in any case no border pixels
2. above the upper threshold these pixels are border pixels
3. in the middle section these pixels are only border pixels if there's a connected chain of other pixels (each also in the middle section) that is connected in any way to a border pixel.

(please see IPP's canny edge detector documentation for more detail)

pre-blur features

In some cases (e.g. if input images are created synthetically) the border intensity image has too hard edges (e.g. from edges from black to white). In this case, the canny edge detector implementation overlooks these borders independent on the given threshold values.

Constructor & Destructor Documentation

◆ CannyOp() [1/2]

icl::filter::CannyOp::CannyOp	(	icl32f	lowThresh = `0`,
		icl32f	highThresh = `255`,
		int	preBlurRadius = `0`
	)

Constructor.

With this Constructor the derivations are computed within the CannyOp. If you already have computed the derivations, use the other Constructor, due to performance reasons.

Parameters

lowThresh	lower threshold
highThresh	upper threshold
preBlurRadius	if r> 0, gaussian kernel with masksize r*2+1 is applied to the input image first

◆ CannyOp() [2/2]

icl::filter::CannyOp::CannyOp	(	UnaryOp *	dxOp,
		UnaryOp *	dyOp,
		icl32f	lowThresh = `0`,
		icl32f	highThresh = `255`,
		bool	deleteOps = `true`,
		int	preBlurRadius = `0`
	)

Constructor.

Parameters

dxOp	the x derivation of the src
dyOp	the y derivation of the src
lowThresh	lower threshold
highThresh	upper threshold
deleteOps	should the internaly created derivations be deleted?
preBlurRadius	if r> 0, gaussian kernel with masksize r*2+1 is applied to the input image first

◆ ~CannyOp()

virtual icl::filter::CannyOp::~CannyOp ( )

virtual

Destructor.

Member Function Documentation

◆ apply() [1/4]

virtual void icl::filter::CannyOp::apply	(	const core::ImgBase *	src,
		core::ImgBase **	dst
	)

virtual

applies the Canny Operator

Parameters

src	the source image
dst	pointer to the destination image

Implements icl::filter::UnaryOp.

◆ apply() [2/4]

virtual void icl::filter::CannyOp::apply	(	const core::ImgBase *	src_x,
		const core::ImgBase *	src_y,
		core::ImgBase **	dst
	)

virtual

applies the Canny Operator

Parameters

src	the source image
dst	pointer to the destination image

◆ apply() [3/4]

virtual void icl::filter::UnaryOp::apply

Import unaryOps apply function without destination image.

◆ apply() [4/4]

virtual const core::ImgBase* icl::filter::UnaryOp::apply

Import unaryOps apply function without destination image.

◆ applyCanny16s()

void icl::filter::CannyOp::applyCanny16s	(	const core::ImgBase *	dx,
		const core::ImgBase *	dy,
		core::ImgBase *	dst,
		int	c
	)

private

◆ applyCanny32f()

void icl::filter::CannyOp::applyCanny32f	(	const core::ImgBase *	dx,
		const core::ImgBase *	dy,
		core::ImgBase *	dst,
		int	c
	)

private

applies canny for one channel

◆ getHighThreshold()

icl32f icl::filter::CannyOp::getHighThreshold ( ) const

returns the upper threshold

Returns: the upper threshold

◆ getLowThreshold()

icl32f icl::filter::CannyOp::getLowThreshold ( ) const

returns the lower threshold

Returns: the lower threshold

◆ getPreBlurRadius()

bool icl::filter::CannyOp::getPreBlurRadius ( ) const

inline

returns current pre-blur feature state

◆ property_callback()

void icl::filter::CannyOp::property_callback ( const Property & p )

private

◆ setPreBlurRadius()

void icl::filter::CannyOp::setPreBlurRadius ( int preBlurRadius )

inline

sets the pre-blur-radius

if r> 0, gaussian kernel with masksize r*2+1 is applied to the input image first

◆ setThresholds()

void icl::filter::CannyOp::setThresholds	(	icl32f	lowThresh,
		icl32f	highThresh
	)

changes the Thresholds

Parameters

lowThresh	lower threshold
highThresh	upper threshold

◆ setUpPreBlurOp()

void icl::filter::CannyOp::setUpPreBlurOp ( )

private

◆ setUseDerivativesInfo()

void icl::filter::CannyOp::setUseDerivativesInfo ( bool use_derivatives )

inline

Member Data Documentation

◆ m_buffer

core::Img32f icl::filter::CannyOp::m_buffer

private

◆ m_cannyBuf

std::vector<icl8u> icl::filter::CannyOp::m_cannyBuf

private

buffer for ippiCanny

◆ m_derivatives

core::ImgBase* icl::filter::CannyOp::m_derivatives[2]

private

◆ m_highT

icl32f icl::filter::CannyOp::m_highT

private

◆ m_lowT

icl32f icl::filter::CannyOp::m_lowT

private

◆ m_ops

UnaryOp* icl::filter::CannyOp::m_ops[2]

private

◆ m_ownOps

bool icl::filter::CannyOp::m_ownOps

private

◆ m_preBlurOp

UnaryOp* icl::filter::CannyOp::m_preBlurOp

private

◆ m_preBlurRadius

int icl::filter::CannyOp::m_preBlurRadius

private

◆ m_use_derivatives_info

bool icl::filter::CannyOp::m_use_derivatives_info

private

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

/Users/alneuman/vm/icl/ICLFilter/src/ICLFilter/CannyOp.h

Public Member Functions

Private Member Functions

Private Attributes

Additional Inherited Members

Detailed Description

Overview

Algorithm

pre-blur features

Constructor & Destructor Documentation

◆ CannyOp() [1/2]

◆ CannyOp() [2/2]

◆ ~CannyOp()

Member Function Documentation

◆ apply() [1/4]

◆ apply() [2/4]

◆ apply() [3/4]

◆ apply() [4/4]

◆ applyCanny16s()

◆ applyCanny32f()

◆ getHighThreshold()

◆ getLowThreshold()

◆ getPreBlurRadius()

◆ property_callback()

◆ setPreBlurRadius()

◆ setThresholds()

◆ setUpPreBlurOp()

◆ setUseDerivativesInfo()

Member Data Documentation

◆ m_buffer

◆ m_cannyBuf

◆ m_derivatives

◆ m_highT

◆ m_lowT

◆ m_ops

◆ m_ownOps

◆ m_preBlurOp

◆ m_preBlurRadius

◆ m_use_derivatives_info