CFeatureExtraction_polarImg.cpp

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/* +------------------------------------------------------------------------+
   |                     Mobile Robot Programming Toolkit (MRPT)            |
   |                          https://www.mrpt.org/                         |
   |                                                                        |
   | Copyright (c) 2005-2020, 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 "vision-precomp.h"  // Precompiled headers

#include <mrpt/vision/CFeatureExtraction.h>

// Universal include for all versions of OpenCV
#include <mrpt/3rdparty/do_opencv_includes.h>

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

// Linear-Polar Transform
// J.L. Blanco, Apr 2009
// Code contributed to OpenCV 1.1.1 long time ago. Removed from MRPT now.

void CFeatureExtraction::internal_computePolarImageDescriptors(
    const mrpt::img::CImage& in_img, CFeatureList& in_features)
{
    MRPT_START
#if MRPT_HAS_OPENCV

    mrpt::system::CTimeLoggerEntry tle(
        profiler, "internal_computePolarImageDescriptors");

    ASSERT_(options.PolarImagesOptions.radius > 1);
    ASSERT_(options.PolarImagesOptions.bins_angle > 1);
    ASSERT_(options.PolarImagesOptions.bins_distance > 1);

    const unsigned int radius = options.PolarImagesOptions.radius;
    const unsigned int patch_w = options.PolarImagesOptions.bins_distance;
    const unsigned int patch_h = options.PolarImagesOptions.bins_angle;

    CImage linpolar_frame(patch_w, patch_h, in_img.getChannelCount());

    // Compute intensity-domain spin images
    for (auto& f : in_features)
    {
        // Overwrite scale with the descriptor scale:
        f.keypoint.octave = radius;

        const auto pt = cv::Point2f(f.keypoint.pt.x, f.keypoint.pt.y);

        const cv::Mat& in = in_img.asCvMatRef();
        cv::Mat& out = linpolar_frame.asCvMatRef();

#if MRPT_OPENCV_VERSION_NUM < 0x300
        IplImage cvin, cvout;
        in_img.getAsIplImage(&cvin);
        linpolar_frame.getAsIplImage(&cvout);
        cvLinearPolar(
            &cvin, &cvout, pt, radius, CV_INTER_LINEAR + CV_WARP_FILL_OUTLIERS);
#elif MRPT_OPENCV_VERSION_NUM < 0x342
        cv::linearPolar(
            in(cv::Rect(
                mrpt::round(pt.x - radius), mrpt::round(pt.y - radius),
                1 + 2 * radius, 1 + 2 * radius)),
            out, pt, radius, CV_INTER_LINEAR + CV_WARP_FILL_OUTLIERS);
#else
        // Latest opencv versions:
        cv::warpPolar(
            in, out, cv::Size(patch_w, patch_h), pt, radius,
            cv::INTER_LINEAR + cv::WARP_FILL_OUTLIERS);
#endif

        // Get the image as a matrix and save as patch:
        f.descriptors.PolarImg.emplace();
        linpolar_frame.getAsMatrix(*f.descriptors.PolarImg);

    }  // end for it

#else
    THROW_EXCEPTION("This method needs MRPT compiled with OpenCV support");
#endif
    MRPT_END
}