tutorial-blob-auto-tracker.cpp

#include <visp/vpDisplayGDI.h>
#include <visp/vpDisplayX.h>
#include <visp/vpDot2.h>
#include <visp/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");
#else
    std::cout << "No image viewer is available..." << std::endl;
#endif
    vpDisplay::display(I);
    vpDisplay::flush(I);

    vpDot2 blob;
    if (learn) {
      // Learn the characteristics of the blob to auto detect
      blob.setGraphics(true);
      blob.setGraphicsThickness(1);
      blob.initTracking(I);
      blob.track(I);
      std::cout << "Blob characteristics: " << std::endl;
      std::cout << " width : " << blob.getWidth() << std::endl;
      std::cout << " height: " << blob.getHeight() << std::endl;
#if VISP_VERSION_INT > VP_VERSION_INT(2,7,0)
      std::cout << " area: " << blob.getArea() << std::endl;
#endif
      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
      blob.setWidth(50);
      blob.setHeight(50);
#if VISP_VERSION_INT > VP_VERSION_INT(2,7,0)
      blob.setArea(1700);
#endif
      blob.setGrayLevelMin(0);
      blob.setGrayLevelMax(30);
      blob.setGrayLevelPrecision(0.8);
      blob.setSizePrecision(0.65);
      blob.setEllipsoidShapePrecision(0.65);
    }

    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:
      blob_list.push_back(blob);
    }
    std::cout << "Number of auto detected blob: " << blob_list.size() << std::endl;
    std::cout << "A click to exit..." << std::endl;

    while(1) {
      vpDisplay::display(I);

      for(std::list<vpDot2>::iterator it=blob_list.begin(); it != blob_list.end(); ++it) {
        (*it).setGraphics(true);
        (*it).setGraphicsThickness(3);
        (*it).track(I);
      }

      vpDisplay::flush(I);

      if (vpDisplay::getClick(I, false))
        break;

      vpTime::wait(40);
    }
  }
  catch(vpException e) {
    std::cout << "Catch an exception: " << e << std::endl;
  }
}