Example: vision_checkerboard_detectors

C++ example source code:

/* +------------------------------------------------------------------------+
   |                     Mobile Robot Programming Toolkit (MRPT)            |
   |                          https://www.mrpt.org/                         |
   |                                                                        |
   | Copyright (c) 2005-2021, Individual contributors, see AUTHORS file     |
   | See: https://www.mrpt.org/Authors - All rights reserved.               |
   | Released under BSD License. See: https://www.mrpt.org/License          |
   +------------------------------------------------------------------------+ */

#include <mrpt/gui.h>
#include <mrpt/img/CImage.h>
#include <mrpt/system/CTimeLogger.h>
#include <mrpt/vision/chessboard_find_corners.h>

#include <iostream>

using namespace std;
using namespace mrpt;
using namespace mrpt::img;
using namespace mrpt::system;
using namespace mrpt::gui;

#include <mrpt/examples_config.h>
std::string myDataDir =
    MRPT_EXAMPLES_BASE_DIRECTORY + string("vision_checkerboard_detectors/");

// ------------------------------------------------------
//              TestCheckerboardDetectors
// ------------------------------------------------------
void TestCheckerboardDetectors()
{
    CTimeLogger timlog;

    // Load img:
    CImage img;
    if (!img.loadFromFile(myDataDir + string("test_1_checkerboard_9x6.jpg")))
        throw std::runtime_error("Can't load demo image!");

    // Detect multiple-checkerboards:
    vector<TPixelCoordf> cornerCoords;
    const unsigned int checkerboard_size_x = 6;
    const unsigned int checkerboard_size_y = 9;

    // Detect:
    timlog.enter("findChessboardCorners [OpenCV]");

    // bool detectOk1 =
    mrpt::vision::findChessboardCorners(
        img, cornerCoords, checkerboard_size_x, checkerboard_size_y,
        true,  // normalize_image
        false  // useScaramuzzaMethod
    );

    timlog.leave("findChessboardCorners [OpenCV]");

    // Draw:
    CImage img_detect1 = img;
    img_detect1.drawChessboardCorners(
        cornerCoords, checkerboard_size_x, checkerboard_size_y);

    timlog.enter("findChessboardCorners [Scaramuzza]");

    // bool detectOk2 =
    mrpt::vision::findChessboardCorners(
        img, cornerCoords, checkerboard_size_x, checkerboard_size_y,
        true,  // normalize_image
        true  // useScaramuzzaMethod
    );

    timlog.leave("findChessboardCorners [Scaramuzza]");

    // Draw:
    CImage img_detect2 = img;
    img_detect2.drawChessboardCorners(
        cornerCoords, checkerboard_size_x, checkerboard_size_y);

    // ASSERT_(detectOk1 && detectOk2);

    // Show results:
    CDisplayWindow win1("Detected checkerboard (OpenCV)");
    win1.showImage(img_detect1);

    CDisplayWindow win2("Detected checkerboard (Scaramuzza)");
    win2.showImage(img_detect2);

    timlog.dumpAllStats();
    timlog.clear();

    // wait till user closes any window:
    while (win1.isOpen() && win2.isOpen())
    {
        std::this_thread::sleep_for(10ms);
    }
}

// ------------------------------------------------------
//                      MAIN
// ------------------------------------------------------
int main()
{
    try
    {
        TestCheckerboardDetectors();
        return 0;
    }
    catch (const std::exception& e)
    {
        std::cerr << "MRPT error: " << mrpt::exception_to_str(e) << std::endl;
        return -1;
    }
    catch (...)
    {
        printf("Untyped exception!!");
        return -1;
    }
}