CFeatureExtraction_SURF.cpp

Go to the documentation of this file.

/* +------------------------------------------------------------------------+
   |                     Mobile Robot Programming Toolkit (MRPT)            |
   |                          https://www.mrpt.org/                         |
   |                                                                        |
   | Copyright (c) 2005-2019, 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/otherlibs/do_opencv_includes.h>

#ifdef HAVE_OPENCV_NONFREE  // MRPT_HAS_OPENCV_NONFREE
#include <opencv2/nonfree/nonfree.hpp>
#endif
#ifdef HAVE_OPENCV_FEATURES2D
#include <opencv2/features2d/features2d.hpp>
#endif
#ifdef HAVE_OPENCV_XFEATURES2D
#include <opencv2/xfeatures2d.hpp>
#endif

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

// Was: MRPT_HAS_OPENCV_NONFREE
#if defined(HAVE_OPENCV_XFEATURES2D) || \
    (MRPT_OPENCV_VERSION_NUM < 0x300 && MRPT_OPENCV_VERSION_NUM >= 0x240)
#define HAVE_OPENCV_WITH_SURF 1
#else
#define HAVE_OPENCV_WITH_SURF 0
#endif

void CFeatureExtraction::extractFeaturesSURF(
    const mrpt::img::CImage& inImg, CFeatureList& feats, unsigned int init_ID,
    unsigned int nDesiredFeatures, const TImageROI& ROI)
{
#if HAVE_OPENCV_WITH_SURF
    mrpt::system::CTimeLoggerEntry tle(profiler, "extractFeaturesSURF");

    using namespace cv;

    const CImage img_grayscale(inImg, FAST_REF_OR_CONVERT_TO_GRAY);
    const Mat& img = img_grayscale.asCvMatRef();

    vector<KeyPoint> cv_feats;  // OpenCV keypoint output vector
    Mat cv_descs;  // OpenCV descriptor output

// gb redesign start -make sure that the Algorithm::create is used only for
// older openCV versions
#if MRPT_OPENCV_VERSION_NUM < 0x300 && MRPT_OPENCV_VERSION_NUM >= 0x240

    Ptr<Feature2D> surf = Algorithm::create<Feature2D>("Feature2D.SURF");
    if (surf.empty())
        CV_Error(
            CV_StsNotImplemented,
            "OpenCV <v3.0 was built without SURF support");

    surf->set("hessianThreshold", options.SURFOptions.hessianThreshold);
    surf->set("nOctaves", options.SURFOptions.nOctaves);
    surf->set("nOctaveLayers", options.SURFOptions.nLayersPerOctave);
    // surf->set("upright", params.upright != 0);
    surf->set("extended", options.SURFOptions.rotation_invariant);

    surf->operator()(img, Mat(), cv_feats, cv_descs);

#else
    Ptr<xfeatures2d::SURF> surf =
        xfeatures2d::SURF::create(100.0, 4, 3, 0, 0);  // gb

    if (surf.empty())
        CV_Error(
            CV_StsNotImplemented, "OpenCV 3.0 was built without SURF support");
    surf->setHessianThreshold(options.SURFOptions.hessianThreshold);
    surf->setNOctaves(options.SURFOptions.nOctaves);
    surf->setNOctaveLayers(options.SURFOptions.nLayersPerOctave);
    // surf->setUpright(params.upright != 0);
    surf->setExtended(options.SURFOptions.rotation_invariant);
    // gb redesign end
    surf->detectAndCompute(img, Mat(), cv_feats, cv_descs);
#endif

    // -----------------------------------------------------------------
    // MRPT Wrapping
    // -----------------------------------------------------------------
    feats.clear();
    unsigned int nCFeats = init_ID;
    int offset = (int)this->options.patchSize / 2 + 1;
    unsigned int imgH = inImg.getHeight();
    unsigned int imgW = inImg.getWidth();

    const size_t n_feats =
        (nDesiredFeatures == 0)
            ? cv_feats.size()
            : std::min((size_t)nDesiredFeatures, cv_feats.size());

    for (size_t i = 0; i < n_feats; i++)
    {
        // Get the OpenCV SURF point
        CFeature ft;
        const KeyPoint& point = cv_feats[i];

        const int xBorderInf = (int)floor(point.pt.x - options.patchSize / 2);
        const int xBorderSup = (int)floor(point.pt.x + options.patchSize / 2);
        const int yBorderInf = (int)floor(point.pt.y - options.patchSize / 2);
        const int yBorderSup = (int)floor(point.pt.y + options.patchSize / 2);

        if (options.patchSize == 0 ||
            ((xBorderSup < (int)imgW) && (xBorderInf > 0) &&
             (yBorderSup < (int)imgH) && (yBorderInf > 0)))
        {
            ft.type = featSURF;
            ft.keypoint.pt.x = point.pt.x;  // X position
            ft.keypoint.pt.y = point.pt.y;  // Y position
            ft.orientation = point.angle;  // Orientation
            ft.keypoint.octave = point.size * 1.2 / 9;  // Scale
            ft.keypoint.ID = nCFeats++;  // Feature ID into extraction
            ft.patchSize = options.patchSize;  // The size of the feature patch

            // Image patch?
            if (options.patchSize > 0)
            {
                mrpt::img::CImage p;
                inImg.extract_patch(
                    p, round(point.pt.x) - offset, round(point.pt.y) - offset,
                    options.patchSize, options.patchSize);

                ft.patch = std::move(p);
            }

            // Get the SURF descriptor
            ft.descriptors.SURF.emplace();
            auto& desc = ft.descriptors.SURF.value();
            desc.resize(cv_descs.cols);
            for (int m = 0; m < cv_descs.cols; ++m)
                desc[m] = cv_descs.at<float>(i, m);

            feats.emplace_back(std::move(ft));

        }  // end if
    }  // end for

#else
    THROW_EXCEPTION(
        "Method not available: MRPT compiled without OpenCV, or against a "
        "version of OpenCV without SURF");
#endif  // MRPT_HAS_OPENCV
}  // end extractFeaturesSURF

void CFeatureExtraction::internal_computeSurfDescriptors(
    const mrpt::img::CImage& inImg, CFeatureList& in_features)
{
#if HAVE_OPENCV_WITH_SURF
    using namespace cv;
    mrpt::system::CTimeLoggerEntry tle(
        profiler, "internal_computeSurfDescriptors");

    if (in_features.empty()) return;

    const CImage img_grayscale(inImg, FAST_REF_OR_CONVERT_TO_GRAY);
    const Mat& img = img_grayscale.asCvMatRef();

    vector<KeyPoint> cv_feats;  // OpenCV keypoint output vector
    Mat cv_descs;  // OpenCV descriptor output

    // Fill in the desired key-points:
    cv_feats.resize(in_features.size());
    for (size_t i = 0; i < in_features.size(); ++i)
    {
        cv_feats[i].pt.x = in_features[i].keypoint.pt.x;
        cv_feats[i].pt.y = in_features[i].keypoint.pt.y;
        cv_feats[i].size = 1 << in_features[i].keypoint.octave;
    }

// Only computes the descriptors:
// gb redesign
#if MRPT_OPENCV_VERSION_NUM < 0x300 && MRPT_OPENCV_VERSION_NUM >= 0x240

    Ptr<Feature2D> surf = Algorithm::create<Feature2D>("Feature2D.SURF");
    if (surf.empty())
        CV_Error(CV_StsNotImplemented, "OpenCV was built without SURF support");
    surf->set("hessianThreshold", options.SURFOptions.hessianThreshold);
    surf->set("nOctaves", options.SURFOptions.nOctaves);
    surf->set("nOctaveLayers", options.SURFOptions.nLayersPerOctave);
    // surf->set("upright", params.upright != 0);
    surf->set("extended", options.SURFOptions.rotation_invariant);

    surf->compute(
        img, cv_feats,
        cv_descs);  // is that correct? the version from above is:
// surf->operator()(img, Mat(), cv_feats, cv_descs);
#else

    Ptr<xfeatures2d::SURF> surf =
        xfeatures2d::SURF::create(100.0, 4, 3, 0, 0);  // gb

    if (surf.empty())
        CV_Error(CV_StsNotImplemented, "OpenCV was built without SURF support");
    surf->setHessianThreshold(options.SURFOptions.hessianThreshold);
    surf->setNOctaves(options.SURFOptions.nOctaves);
    surf->setNOctaveLayers(options.SURFOptions.nLayersPerOctave);
    // surf->setUpright(params.upright != 0);
    surf->setExtended(options.SURFOptions.rotation_invariant);

    surf->detectAndCompute(img, Mat(), cv_feats, cv_descs);
#endif
    // gb redesign end
    // -----------------------------------------------------------------
    // MRPT Wrapping
    // -----------------------------------------------------------------
    int i = 0;
    for (auto& ft : in_features)
    {
        // Get the OpenCV SURF point
        const KeyPoint& point = cv_feats[i];

        ft.orientation = point.angle;
        ft.keypoint.octave = point.octave;

        // Get the SURF descriptor
        ft.descriptors.SURF.emplace();
        auto& desc = ft.descriptors.SURF.value();
        desc.resize(cv_descs.cols);
        for (int m = 0; m < cv_descs.cols; ++m)
            desc[m] = cv_descs.at<float>(i, m);

        i++;
    }

#else
    THROW_EXCEPTION(
        "Method not available: MRPT compiled without OpenCV, or against a "
        "version of OpenCV without SURF");
#endif  // MRPT_HAS_OPENCV
}  // end internal_computeSurfDescriptors