CFeatureExtraction_polarImg.cpp

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/* +------------------------------------------------------------------------+
   |                     Mobile Robot Programming Toolkit (MRPT)            |
   |                          http://www.mrpt.org/                          |
   |                                                                        |
   | Copyright (c) 2005-2017, Individual contributors, see AUTHORS file     |
   | See: http://www.mrpt.org/Authors - All rights reserved.                |
   | Released under BSD License. See details in http://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>

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

/****************************************************************************************
                                                                   Linear-Polar Transform
  J.L. Blanco, Apr 2009
****************************************************************************************/
#if MRPT_HAS_OPENCV && MRPT_OPENCV_VERSION_NUM < 0x111
void my_cvLinearPolar(
        const CvArr* srcarr, CvArr* dstarr, CvPoint2D32f center, double maxRadius,
        int flags)
{
        CvMat* mapx = 0;
        CvMat* mapy = 0;
        float* buf = 0;

        CV_FUNCNAME("cvLinPolar");

        __BEGIN__;

        CvMat srcstub, *src = (CvMat *)srcarr;
        CvMat dststub, *dst = (CvMat *)dstarr;
        CvSize ssize, dsize;

        CV_CALL(src = cvGetMat(srcarr, &srcstub, 0, 0));
        CV_CALL(dst = cvGetMat(dstarr, &dststub, 0, 0));

        if (!CV_ARE_TYPES_EQ(src, dst)) CV_ERROR(CV_StsUnmatchedFormats, "");

        ssize.width = src->cols;
        ssize.height = src->rows;
        dsize.width = dst->cols;
        dsize.height = dst->rows;

        CV_CALL(mapx = cvCreateMat(dsize.height, dsize.width, CV_32F));
        CV_CALL(mapy = cvCreateMat(dsize.height, dsize.width, CV_32F));

        if (!(flags & CV_WARP_INVERSE_MAP))
        {
                int phi, rho;

                for (phi = 0; phi < dsize.height; phi++)
                {
                        double cp = cos(phi * 2 * CV_PI / (dsize.height - 1));
                        double sp = sin(phi * 2 * CV_PI / (dsize.height - 1));
                        float* mx = (float*)(mapx->data.ptr + phi * mapx->step);
                        float* my = (float*)(mapy->data.ptr + phi * mapy->step);

                        for (rho = 0; rho < dsize.width; rho++)
                        {
                                double r = maxRadius * (rho + 1) / double(dsize.width - 1);
                                double x = r * cp + center.x;
                                double y = r * sp + center.y;

                                mx[rho] = (float)x;
                                my[rho] = (float)y;
                        }
                }
        }
        else
        {
                int x, y;
                CvMat bufx, bufy, bufp, bufa;
                const double ascale = (ssize.height - 1) / (2 * CV_PI);
                const double pscale = (ssize.width - 1) / maxRadius;

                CV_CALL(buf = (float*)cvAlloc(4 * dsize.width * sizeof(buf[0])));

                bufx = cvMat(1, dsize.width, CV_32F, buf);
                bufy = cvMat(1, dsize.width, CV_32F, buf + dsize.width);
                bufp = cvMat(1, dsize.width, CV_32F, buf + dsize.width * 2);
                bufa = cvMat(1, dsize.width, CV_32F, buf + dsize.width * 3);

                for (x = 0; x < dsize.width; x++) bufx.data.fl[x] = (float)x - center.x;

                for (y = 0; y < dsize.height; y++)
                {
                        float* mx = (float*)(mapx->data.ptr + y * mapx->step);
                        float* my = (float*)(mapy->data.ptr + y * mapy->step);

                        for (x = 0; x < dsize.width; x++)
                                bufy.data.fl[x] = (float)y - center.y;

                        cvCartToPolar(&bufx, &bufy, &bufp, &bufa, 0);

                        for (x = 0; x < dsize.width; x++) bufp.data.fl[x] += 1.f;

                        for (x = 0; x < dsize.width; x++)
                        {
                                double rho = bufp.data.fl[x] * pscale;
                                double phi = bufa.data.fl[x] * ascale;
                                mx[x] = (float)rho;
                                my[x] = (float)phi;
                        }
                }
        }

        cvRemap(src, dst, mapx, mapy, flags, cvScalarAll(0));

        __END__;

        cvFree(&buf);
        cvReleaseMat(&mapx);
        cvReleaseMat(&mapy);
}
#endif

/************************************************************************************************
                                                                computePolarImageDescriptors
************************************************************************************************/
void CFeatureExtraction::internal_computePolarImageDescriptors(
        const mrpt::utils::CImage& in_img, CFeatureList& in_features) const
{
        MRPT_START
#if MRPT_HAS_OPENCV

        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 (CFeatureList::iterator it = in_features.begin();
                 it != in_features.end(); ++it)
        {
                // Overwrite scale with the descriptor scale:
                (*it)->scale = radius;

// Use OpenCV to convert:
#if MRPT_OPENCV_VERSION_NUM < 0x111
                my_cvLinearPolar(       // Use version embedded above in this file
#else
                cvLinearPolar(          // Use version sent to OpenCV
#endif
                        in_img.getAs<IplImage>(),
                        linpolar_frame.getAs<IplImage>(),
                        cvPoint2D32f( (*it)->x,(*it)->y ),
                        radius,
                        CV_INTER_LINEAR+CV_WARP_FILL_OUTLIERS );

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

        }  // end for it

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