#include <visp3/core/vpColor.h>

Inheritance diagram for vpColor:

Public Types
enum	vpColorIdentifier { id_black = 0 , id_white , id_lightGray , id_gray , id_darkGray , id_lightRed , id_red , id_darkRed , id_lightGreen , id_green , id_darkGreen , id_lightBlue , id_blue , id_darkBlue , id_yellow , id_cyan , id_orange , id_purple , id_unknown }

enum	AlphaDefault { alpha_default = 255 }

Public Member Functions
	vpColor ()

	vpColor (unsigned char r, unsigned char g, unsigned char b, vpColor::vpColorIdentifier cid=vpColor::id_unknown)

	vpColor (unsigned char r, unsigned char g, unsigned char b, unsigned char alpha, vpColor::vpColorIdentifier cid=vpColor::id_unknown)

	vpColor (const vpColor &color, unsigned char alpha)

virtual	~vpColor ()

void	setColor (unsigned char r, unsigned char g, unsigned char b, unsigned char a=vpRGBa::alpha_default)

bool	operator== (const vpRGBa &v) const

bool	operator!= (const vpRGBa &v) const

vpColVector	operator- (const vpRGBa &v) const

vpColVector	operator- (const vpColVector &v) const

vpRGBa	operator+ (const vpRGBa &v) const

vpColVector	operator+ (const vpColVector &v) const

vpColVector	operator* (const float &v) const

vpColVector	operator* (const double &v) const

bool	operator< (const vpRGBa &v) const

bool	operator> (const vpRGBa &v) const

Static Public Member Functions
static vpColor	getColor (const unsigned int &i)

Public Attributes
vpColorIdentifier	id

unsigned char	R

unsigned char	G

unsigned char	B

unsigned char	A

Static Public Attributes
static const vpColor	black = vpColor(0, 0, 0, id_black)

static const vpColor	white = vpColor(255, 255, 255, id_white)

static const vpColor	lightGray = vpColor(192, 192, 192, id_lightGray)

static const vpColor	gray = vpColor(128, 128, 128, id_gray)

static const vpColor	darkGray = vpColor(64, 64, 64, id_darkGray)

static const vpColor	lightRed = vpColor(255, 140, 140, id_lightRed)

static const vpColor	red = vpColor(255, 0, 0, id_red)

static const vpColor	darkRed = vpColor(128, 0, 0, id_darkRed)

static const vpColor	lightGreen = vpColor(140, 255, 140, id_lightGreen)

static const vpColor	green = vpColor(0, 255, 0, id_green)

static const vpColor	darkGreen = vpColor(0, 128, 0, id_darkGreen)

static const vpColor	lightBlue = vpColor(140, 140, 255, id_lightBlue)

static const vpColor	blue = vpColor(0, 0, 255, id_blue)

static const vpColor	darkBlue = vpColor(0, 0, 128, id_darkBlue)

static const vpColor	yellow = vpColor(255, 255, 0, id_yellow)

static const vpColor	cyan = vpColor(0, 255, 255, id_cyan)

static const vpColor	orange = vpColor(255, 165, 0, id_orange)

static const vpColor	purple = vpColor(128, 0, 128, id_purple)

static const vpColor	none = vpColor(0, 0, 0, id_unknown)

static const unsigned int	nbColors = 18

static const vpColor	allColors []

Friends
VISP_EXPORT bool	operator== (const vpColor &c1, const vpColor &c2)

VISP_EXPORT bool	operator!= (const vpColor &c1, const vpColor &c2)

Related Functions
(Note that these are not member functions.)
VISP_EXPORT std::ostream &	operator<< (std::ostream &os, const vpRGBa &rgba)

Detailed Description

Class to define RGB colors available for display functionalities.

You may use predefined colors:
- vpColor::black, vpColor::white,
- vpColor::lightGray, vpColor::gray, vpColor::darkGray,
- vpColor::lightRed, vpColor::red, vpColor::darkRed,
- vpColor::lightGreen, vpColor::green, vpColor::darkGreen,
- vpColor::lightBlue, vpColor::blue, vpColor::darkBlue,
- vpColor::yellow, vpColor::cyan, vpColor::orange, vpColor::purple
  vpColor color1(vpColor::lightGreen);
  
  vpColor color2 = vpColor::lightGreen;
  
  vpColor
  Class to define RGB colors available for display functionalities.
  Definition: vpColor.h:157
  
  vpColor::lightGreen
  static const vpColor lightGreen
  Definition: vpColor.h:219
or specify your own color by settings its R,G,B values.
unsigned char R=140, G=255, B=140;

vpColor color1(R, G, B);

vpColor color2;

color2.setColor(R, G, B);

vpColor::setColor
void setColor(unsigned char r, unsigned char g, unsigned char b, unsigned char a=vpRGBa::alpha_default)
Definition: vpColor.h:296

vpRGBa::B
unsigned char B
Blue component.
Definition: vpRGBa.h:169

vpRGBa::R
unsigned char R
Red component.
Definition: vpRGBa.h:167

vpRGBa::G
unsigned char G
Green component.
Definition: vpRGBa.h:168

Warning

Since ViSP 3.3.1 or higher we introduce the alpha channel support for color transparency. This feature is for the moment only supported using vpDisplayOpenCV. To use transparency you may set an additional alpha parameter. When the value is 255, there is no transparency. A value equal to 0 means that the color is completely transparent. The following examples show how to introduce transparency:

using predefined colors:
unsigned char alpha = 128;

vpColor color1(vpColor::lightGreen, alpha);

vpColor color2 = vpColor(vpColor::lightGreen, alpha);

vpColor::vpColor
vpColor()
Definition: vpColor.h:241
or using user defined colors:
unsigned char R=140, G=255, B=140, alpha=128;

vpColor color1(R, G, B, alpha);

vpColor color2;

color2.setColor(R, G, B, alpha);

See displayOpenCV.cpp example for complete usage when displaying filled transparent circles or rectangles.

An identifier vpColor::vpColorIdentifier is associated to each color. This identifier is useful to determine if a color is predefined or specified by it R,G,B values. In that last case, the identifier is always set to vpColor::id_unknown.

The example below shows how to display geometric features in a display overlay using predefined colors (here the blue color to draw a circle) and a specific brown color (used to draw a rectangle).

#include <visp3/gui/vpDisplayD3D.h>
#include <visp3/gui/vpDisplayGDI.h>
#include <visp3/gui/vpDisplayGTK.h>
#include <visp3/gui/vpDisplayOpenCV.h>
#include <visp3/gui/vpDisplayX.h>
 
#ifdef ENABLE_VISP_NAMESPACE
using namespace VISP_NAMESPACE_NAME;
#endif
 
int main()
{
  vpImage<unsigned char> I(240, 320); // Create a black grey level image
 
  vpDisplay *d;
 
  // Depending on the detected third party libraries, we instantiate here the
  // first video device which is available
#if defined(VISP_HAVE_X11)
  d = new vpDisplayX;
#elif defined(VISP_HAVE_GTK)
  d = new vpDisplayGTK;
#elif defined(VISP_HAVE_GDI)
  d = new vpDisplayGDI;
#elif defined(VISP_HAVE_D3D9)
  d = new vpDisplayD3D;
#elif defined(HAVE_OPENCV_HIGHGUI)
  d = new vpDisplayOpenCV;
#endif
 
  // Initialize the display with the image I. Display and image are
  // now link together.
#ifdef VISP_HAVE_DISPLAY
  d->init(I);
#endif
 
  // Set the display background with image I content
  vpDisplay::display(I);
 
  // Draw a filled circle with the predefined blue color
  vpDisplay::displayCircle(I, 100, 200, 30, vpColor::blue, true);
 
  // Creation of a new brown color with its RGB values
  vpColor color(128, 100, 50);
 
  // Draw a brown rectangle in the display overlay (foreground)
  vpDisplay::displayRectangle(I, 10, 10, 100, 20, color, true);
 
  // Flush the foreground and background display
  vpDisplay::flush(I);
 
  delete d;
}

Examples: SickLDMRS-Process.cpp, catchParticleFilter.cpp, displayOpenCV.cpp, servoMomentImage.cpp, servoMomentPoints.cpp, servoMomentPolygon.cpp, servoViper850Point2DArtVelocity-jointAvoidance-basic.cpp, servoViper850Point2DArtVelocity-jointAvoidance-gpa.cpp, servoViper850Point2DArtVelocity-jointAvoidance-large.cpp, testGenericTracker.cpp, tutorial-draw-circle.cpp, tutorial-megapose-live-single-object-tracking.cpp, tutorial-munkres-assignment.cpp, tutorial-pf-curve-fitting-all.cpp, and tutorial-pf-curve-fitting-pf.cpp.

Definition at line 156 of file vpColor.h.

Member Enumeration Documentation

◆ AlphaDefault

enum vpRGBa::AlphaDefault

inherited

Enumerator
alpha_default

Definition at line 67 of file vpRGBa.h.

◆ vpColorIdentifier

enum vpColor::vpColorIdentifier

Predefined colors identifier.

Enumerator
id_black	Identifier associated to the predefined vpColor::black color.
id_white	Identifier associated to the predefined vpColor::white color.
id_lightGray	Identifier associated to the predefined vpColor::lightGray color.
id_gray	Identifier associated to the predefined vpColor::gray color.
id_darkGray	Identifier associated to the predefined vpColor::darkGray color.
id_lightRed	Identifier associated to the predefined vpColor::lightRed color.
id_red	Identifier associated to the predefined vpColor::red color.
id_darkRed	Identifier associated to the predefined vpColor::darkRed color.
id_lightGreen	Identifier associated to the predefined vpColor::lightGreen color.
id_green	Identifier associated to the predefined vpColor::green color.
id_darkGreen	Identifier associated to the predefined vpColor::darkGreen color.
id_lightBlue	Identifier associated to the predefined vpColor::lightBlue color.
id_blue	Identifier associated to the predefined vpColor::blue color.
id_darkBlue	Identifier associated to the predefined vpColor::darkBlue color.
id_yellow	Identifier associated to the predefined vpColor::yellow color.
id_cyan	Identifier associated to the predefined vpColor::cyan color.
id_orange	Identifier associated to the predefined vpColor::orange color.
id_purple	Identifier associated to the predefined vpColor::purple color.
id_unknown	Identifier associated to unknowned colors. By unknowned, we mean not a predefined color. This identifier can also be used to know the number of predefined colors.

Definition at line 160 of file vpColor.h.

Constructor & Destructor Documentation

◆ vpColor() [1/4]

vpColor::vpColor ( )

inline

Default constructor. All the colors components are set to zero.

The color identifier is set to vpColor::id_unknown to indicate that this color is not a predefined one.

Definition at line 241 of file vpColor.h.

◆ vpColor() [2/4]

vpColor::vpColor	(	unsigned char	r,
		unsigned char	g,
		unsigned char	b,
		vpColor::vpColorIdentifier	cid = `vpColor::id_unknown`
	)

inline

Construct a color from its RGB values.

Parameters

r	: Red component.
g	: Green component.
b	: Blue component.
cid	: The color identifier to indicate if this color is or not a predefined one.

Definition at line 252 of file vpColor.h.

◆ vpColor() [3/4]

vpColor::vpColor	(	unsigned char	r,
		unsigned char	g,
		unsigned char	b,
		unsigned char	alpha,
		vpColor::vpColorIdentifier	cid = `vpColor::id_unknown`
	)

inline

Construct a color from its RGB values and alpha channel.

Parameters

r	: Red component.
g	: Green component.
b	: Blue component.
alpha	: Alpha channel for transparency.
cid	: The color identifier to indicate if this color is or not a predefined one.

Definition at line 267 of file vpColor.h.

◆ vpColor() [4/4]

vpColor::vpColor	(	const vpColor &	color,
		unsigned char	alpha
	)

inline

Construct a color with an alpha channel.

Parameters

color	: RGB color.
alpha	: Alpha channel for transparency.

Definition at line 277 of file vpColor.h.

◆ ~vpColor()

virtual vpColor::~vpColor ( )

inlinevirtual

Default destructor.

Definition at line 280 of file vpColor.h.

Member Function Documentation

◆ getColor()

static vpColor vpColor::getColor ( const unsigned int & i )

inlinestatic

Get a predefined color

Parameters

i	: color indice

Examples: testConnectedComponents.cpp, tutorial-apriltag-detector-live-T265-realsense.cpp, tutorial-apriltag-detector-live-rgbd-realsense.cpp, tutorial-apriltag-detector-live-rgbd-structure-core.cpp, tutorial-apriltag-detector-live.cpp, tutorial-apriltag-detector.cpp, and tutorial-connected-components.cpp.

Definition at line 311 of file vpColor.h.

References allColors, and nbColors.

Referenced by vpIoTools::readConfigVar().

◆ operator!=()

bool vpRGBa::operator!= ( const vpRGBa & v ) const

inherited

Compare two color pixels.

Returns: true if the images are different, false if they are the same.

Definition at line 155 of file vpRGBa.cpp.

References vpRGBa::A, vpRGBa::B, vpRGBa::G, and vpRGBa::R.

◆ operator*() [1/2]

vpColVector vpRGBa::operator* ( const double & v ) const

inherited

Multiplication operator : v * "this".

Parameters

v	: Value to multiply.

Returns: v * "this"

Definition at line 254 of file vpRGBa.cpp.

References vpRGBa::A, vpRGBa::B, vpRGBa::G, and vpRGBa::R.

◆ operator*() [2/2]

vpColVector vpRGBa::operator* ( const float & v ) const

inherited

Multiplication operator : v * "this".

Parameters

v	: Value to multiply.

Returns: v * "this"

Definition at line 235 of file vpRGBa.cpp.

References vpRGBa::A, vpRGBa::B, vpRGBa::G, and vpRGBa::R.

◆ operator+() [1/2]

vpColVector vpRGBa::operator+ ( const vpColVector & v ) const

inherited

Addition operator : "this" + v.

Parameters

v	: Color to add to the current object "this".

Returns: "this" + v

Definition at line 216 of file vpRGBa.cpp.

References vpRGBa::A, vpRGBa::B, vpRGBa::G, and vpRGBa::R.

◆ operator+() [2/2]

vpRGBa vpRGBa::operator+ ( const vpRGBa & v ) const

inherited

Addition operator : "this" + v.

Parameters

v	: Color to add to the current object "this".

Returns: "this" + v

Warning: in case of overflow : e.g. 128+128 returns 0 for all 4 channels

Definition at line 182 of file vpRGBa.cpp.

References vpRGBa::A, vpRGBa::B, vpRGBa::G, and vpRGBa::R.

◆ operator-() [1/2]

vpColVector vpRGBa::operator- ( const vpColVector & v ) const

inherited

subtraction operator : "this" - v.

Parameters

v	: Color to subtract to the current object "this".

Returns: "this" - v

Definition at line 197 of file vpRGBa.cpp.

References vpRGBa::A, vpRGBa::B, vpRGBa::G, and vpRGBa::R.

◆ operator-() [2/2]

vpColVector vpRGBa::operator- ( const vpRGBa & v ) const

inherited

subtraction operator : "this" - v.

Parameters

v	: Color to subtract to the current object "this".

Returns: "this" - v

Definition at line 162 of file vpRGBa.cpp.

References vpRGBa::A, vpRGBa::B, vpRGBa::G, and vpRGBa::R.

◆ operator<()

bool vpRGBa::operator< ( const vpRGBa & v ) const

inherited

Definition at line 268 of file vpRGBa.cpp.

References vpRGBa::B, vpRGBa::G, and vpRGBa::R.

◆ operator==()

bool vpRGBa::operator== ( const vpRGBa & v ) const

inherited

Compare two RGBa values.

Returns: true if the values are the same, false otherwise.

Definition at line 146 of file vpRGBa.cpp.

References vpRGBa::A, vpRGBa::B, vpRGBa::G, and vpRGBa::R.

◆ operator>()

bool vpRGBa::operator> ( const vpRGBa & v ) const

inherited

Definition at line 276 of file vpRGBa.cpp.

References vpRGBa::B, vpRGBa::G, and vpRGBa::R.

◆ setColor()

void vpColor::setColor	(	unsigned char	r,
		unsigned char	g,
		unsigned char	b,
		unsigned char	a = `vpRGBa::alpha_default`
	)

inline

Set a color from its RGB values.

Parameters

r	: Red component.
g	: Green component.
b	: Blue component.
a	: Alpha component for transparency.

The color identifier is set to vpColor::id_unknown to indicate that this color is not a predefined one.

Definition at line 296 of file vpColor.h.

Friends And Related Function Documentation

◆ operator!=

VISP_EXPORT bool operator!=	(	const vpColor &	c1,
		const vpColor &	c2
	)

friend

Compare two colors.

Return true if the R,G,B components are different.

Parameters

c1,c2 : Color to compare.

Definition at line 143 of file vpColor.cpp.

◆ operator<<()

VISP_EXPORT std::ostream & operator<<	(	std::ostream &	os,
		const vpRGBa &	rgba
	)

The following code prints the intensity of the pixel in the middle of the image:

#include <visp3/core/vpImage.h>
 
#ifdef ENABLE_VISP_NAMESPACE
using namespace VISP_NAMESPACE_NAME;
#endif
 
int main()
{
  vpImage<vpRGBa> I(480,640);
 
  std::cout << "RGB: " << I[240][320] << std::endl;
 
  return 0;
}

Definition at line 326 of file vpRGBa.cpp.

◆ operator==

VISP_EXPORT bool operator==	(	const vpColor &	c1,
		const vpColor &	c2
	)

friend

Compare two colors.

Return true if the R,G,B components are the same.

Parameters

c1,c2 : Color to compare.

Definition at line 130 of file vpColor.cpp.

Member Data Documentation

◆ A

unsigned char vpRGBa::A

inherited

Additionnal component.

Examples: testImageDifference.cpp, and testPerformanceLUT.cpp.

Definition at line 170 of file vpRGBa.h.

Referenced by VISP_NAMESPACE_NAME::adjust(), vpImageConvert::convert(), vpImageTools::imageDifference(), vpImageTools::imageDifferenceAbsolute(), vpImageConvert::merge(), vpRGBa::operator!=(), vpRGBa::operator*(), vpRGBa::operator+(), vpRGBa::operator-(), vpRGBa::operator=(), vpRGBa::operator==(), vpPanda3DRGBRenderer::setBackgroundImage(), and VISP_NAMESPACE_NAME::stretchContrast().

◆ allColors

vpColor const vpColor::allColors

static

Initial value:

= { vpColor::blue,       
                                                       vpColor::green,      
                                                       vpColor::red,        
                                                       vpColor::cyan,       
                                                       vpColor::purple,     
                                                       vpColor::yellow,     
                                                       vpColor::orange,     
                                                       vpColor::lightBlue,  
                                                       vpColor::lightGreen, 
                                                       vpColor::lightRed,   
                                                       vpColor::darkBlue,   
                                                       vpColor::darkGreen,  
                                                       vpColor::darkRed,    
                                                       vpColor::lightGray,  
                                                       vpColor::gray,       
                                                       vpColor::darkGray,   
                                                       vpColor::black,      
                                                       vpColor::white }