Visual Servoing Platform  version 3.6.1 under development (2024-05-28)
#include <visp3/blob/vpDot2.h>
#include <visp3/gui/vpDisplayGDI.h>
#include <visp3/gui/vpDisplayOpenCV.h>
#include <visp3/gui/vpDisplayX.h>
#include <visp3/io/vpImageIo.h>
int main()
try {
bool learn = false;
vpImage<unsigned char> I; // Create a gray level image container
vpImageIo::read(I, "./target.pgm");
#if defined(VISP_HAVE_X11)
vpDisplayX d(I, 0, 0, "Camera view");
#elif defined(VISP_HAVE_GDI)
vpDisplayGDI d(I, 0, 0, "Camera view");
#elif defined(HAVE_OPENCV_HIGHGUI)
vpDisplayOpenCV d(I, 0, 0, "Camera view");
std::cout << "No image viewer is available..." << std::endl;
vpDot2 blob;
if (learn) {
// Learn the characteristics of the blob to auto detect
std::cout << "Blob characteristics: " << std::endl;
std::cout << " width : " << blob.getWidth() << std::endl;
std::cout << " height: " << blob.getHeight() << std::endl;
std::cout << " area: " << blob.getArea() << std::endl;
std::cout << " gray level min: " << blob.getGrayLevelMin() << std::endl;
std::cout << " gray level max: " << blob.getGrayLevelMax() << std::endl;
std::cout << " grayLevelPrecision: " << blob.getGrayLevelPrecision() << std::endl;
std::cout << " sizePrecision: " << blob.getSizePrecision() << std::endl;
std::cout << " ellipsoidShapePrecision: " << blob.getEllipsoidShapePrecision() << std::endl;
else {
// Set blob characteristics for the auto detection
std::list<vpDot2> blob_list;
blob.searchDotsInArea(I, 0, 0, I.getWidth(), I.getHeight(), blob_list);
if (learn) {
// The blob that is tracked by initTracking() is not in the list of auto
// detected blobs We add it:
std::cout << "Number of auto detected blob: " << blob_list.size() << std::endl;
std::cout << "A click to exit..." << std::endl;
while (1) {
for (std::list<vpDot2>::iterator it = blob_list.begin(); it != blob_list.end(); ++it) {
if (vpDisplay::getClick(I, false))
} catch (const vpException &e) {
std::cout << "Catch an exception: " << e << std::endl;
Display for windows using GDI (available on any windows 32 platform).
Definition: vpDisplayGDI.h:128
The vpDisplayOpenCV allows to display image using the OpenCV library. Thus to enable this class OpenC...
Use the X11 console to display images on unix-like OS. Thus to enable this class X11 should be instal...
Definition: vpDisplayX.h:128
static bool getClick(const vpImage< unsigned char > &I, bool blocking=true)
static void display(const vpImage< unsigned char > &I)
static void flush(const vpImage< unsigned char > &I)
This tracker is meant to track a blob (connex pixels with same gray level) on a vpImage.
Definition: vpDot2.h:124
unsigned int getGrayLevelMin() const
Definition: vpDot2.h:214
unsigned int getGrayLevelMax() const
Definition: vpDot2.h:220
void track(const vpImage< unsigned char > &I, bool canMakeTheWindowGrow=true)
Definition: vpDot2.cpp:435
void setGraphics(bool activate)
Definition: vpDot2.h:313
void setGraphicsThickness(unsigned int t)
Definition: vpDot2.h:321
double getEllipsoidShapePrecision() const
Definition: vpDot2.cpp:642
void searchDotsInArea(const vpImage< unsigned char > &I, int area_u, int area_v, unsigned int area_w, unsigned int area_h, std::list< vpDot2 > &niceDots)
Definition: vpDot2.cpp:975
void setGrayLevelMax(const unsigned int &max)
Definition: vpDot2.h:351
double getArea() const
Definition: vpDot2.cpp:619
void setSizePrecision(const double &sizePrecision)
Definition: vpDot2.cpp:747
void setGrayLevelPrecision(const double &grayLevelPrecision)
Definition: vpDot2.cpp:717
void setGrayLevelMin(const unsigned int &min)
Definition: vpDot2.h:333
void setHeight(const double &height)
Definition: vpDot2.cpp:686
double getSizePrecision() const
Definition: vpDot2.cpp:633
double getGrayLevelPrecision() const
Definition: vpDot2.cpp:626
void setWidth(const double &width)
Definition: vpDot2.cpp:674
double getWidth() const
Definition: vpDot2.cpp:605
void setEllipsoidShapePrecision(const double &ellipsoidShapePrecision)
Definition: vpDot2.cpp:792
void setArea(const double &area)
Definition: vpDot2.cpp:698
void initTracking(const vpImage< unsigned char > &I, unsigned int size=0)
Definition: vpDot2.cpp:254
double getHeight() const
Definition: vpDot2.cpp:612
error that can be emitted by ViSP classes.
Definition: vpException.h:59
static void read(vpImage< unsigned char > &I, const std::string &filename, int backend=IO_DEFAULT_BACKEND)
Definition: vpImageIo.cpp:143
unsigned int getWidth() const
Definition: vpImage.h:245
unsigned int getHeight() const
Definition: vpImage.h:184
VISP_EXPORT int wait(double t0, double t)