TCamera.cpp

Go to the documentation of this file.

/* +---------------------------------------------------------------------------+
   |                     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 "base-precomp.h"  // Precompiled headers

#include <mrpt/utils/TCamera.h>
#include <mrpt/utils/CConfigFileMemory.h>
#include <mrpt/math/matrix_serialization.h>  // For "<<" ">>" operators.
#include <mrpt/math/utils_matlab.h>

using namespace mrpt::utils;
using namespace mrpt::math;
using namespace std;


/* Implements serialization for the TCamera struct as it will be included within CObservations objects */
IMPLEMENTS_SERIALIZABLE( TCamera, CSerializable, mrpt::utils )

/** Dumps all the parameters as a multi-line string, with the same format than \a saveToConfigFile.  \sa saveToConfigFile */
std::string TCamera::dumpAsText() const
{
        mrpt::utils::CConfigFileMemory cfg;
        saveToConfigFile("",cfg);
        return cfg.getContent();
}


// WriteToStream
void TCamera::writeToStream( CStream &out, int *version ) const
{
        if( version )
                *version = 2;
        else
        {
                out << focalLengthMeters;
                for(unsigned int k = 0; k < 5; k++) out << dist[k];
                out << intrinsicParams;
                // version 0 did serialize here a "CMatrixDouble15"
                out << nrows << ncols; // New in v2
        } // end else
}

// ReadFromStream
void TCamera::readFromStream( CStream &in, int version )
{
        switch( version )
        {
        case 0:
        case 1:
        case 2:
                {
                        in >> focalLengthMeters;

                        for(unsigned int k = 0; k < 5; k++)
                                in >> dist[k];

                        in >> intrinsicParams;

                        if (version==0)
                        {
                                CMatrixDouble15 __distortionParams;
                                in >> __distortionParams;
                        }

                        if (version>=2)
                                in >> nrows >> ncols;
                        else {
                                nrows = 480;
                                ncols = 640;
                        }


                } break;
        default:
                MRPT_THROW_UNKNOWN_SERIALIZATION_VERSION( version )
        }
}

/*---------------------------------------------------------------
  Implements the writing to a mxArray for Matlab
 ---------------------------------------------------------------*/
#if MRPT_HAS_MATLAB
// Add to implement mexplus::from template specialization
IMPLEMENTS_MEXPLUS_FROM( mrpt::utils::TCamera )

mxArray* TCamera::writeToMatlab() const
{
        const char* fields[] = {"K","dist","f","ncols","nrows"};
        mexplus::MxArray params_struct( mexplus::MxArray::Struct(sizeof(fields)/sizeof(fields[0]),fields) );
        params_struct.set("K", mrpt::math::convertToMatlab(this->intrinsicParams));
        params_struct.set("dist", mrpt::math::convertToMatlab(this->dist));
        params_struct.set("f", this->focalLengthMeters);
        params_struct.set("ncols", this->ncols);
        params_struct.set("nrows", this->nrows);
        return params_struct.release();
}
#endif

/**  Save as a config block:
  *  \code
  *  [SECTION]
  *  resolution = NCOLS NROWS
  *  cx         = CX
  *  cy         = CY
  *  fx         = FX
  *  fy         = FY
  *  dist       = K1 K2 T1 T2 T3
  *  focal_length = FOCAL_LENGTH
  *  \endcode
  */
void TCamera::saveToConfigFile(const std::string &section,  mrpt::utils::CConfigFileBase &cfg ) const
{
        cfg.write(section,"resolution",format("[%u %u]",(unsigned int)ncols,(unsigned int)nrows));
        cfg.write(section,"cx", format("%.05f",cx()) );
        cfg.write(section,"cy", format("%.05f",cy()) );
        cfg.write(section,"fx", format("%.05f",fx()) );
        cfg.write(section,"fy", format("%.05f",fy()) );
        cfg.write(section,"dist", format("[%e %e %e %e %e]", dist[0],dist[1],dist[2],dist[3],dist[4] ) );
        if (focalLengthMeters!=0) cfg.write(section,"focal_length", focalLengthMeters );
}

/**  Load all the params from a config source, in the format described in saveToConfigFile()
  */
void TCamera::loadFromConfigFile(const std::string &section,  const mrpt::utils::CConfigFileBase &cfg )
{
        vector<uint64_t>  out_res;
        cfg.read_vector(section,"resolution",vector<uint64_t>(),out_res,true);
        if (out_res.size()!=2) THROW_EXCEPTION("Expected 2-length vector in field 'resolution'");
        ncols = out_res[0];
        nrows = out_res[1];

        double fx, fy, cx, cy;
    fx = cfg.read_double(section,"fx",0, true);
    fy = cfg.read_double(section,"fy",0, true);
    cx = cfg.read_double(section,"cx",0, true);
    cy = cfg.read_double(section,"cy",0, true);

    if( fx < 2.0 ) fx *= ncols;
    if( fy < 2.0 ) fy *= nrows;
    if( cx < 2.0 ) cx *= ncols;
    if( cy < 2.0 ) cy *= nrows;

        setIntrinsicParamsFromValues( fx, fy, cx, cy );

        CVectorDouble dists;
        cfg.read_vector(section,"dist",CVectorDouble(), dists, true);
        if (dists.size()!=4 && dists.size()!=5) THROW_EXCEPTION("Expected 4 or 5-length vector in field 'dist'");

        dist.Constant(0);
        for (CVectorDouble::Index i=0;i<dists.size();i++)
                dist[i] = dists[i];

        focalLengthMeters = cfg.read_double(section,"focal_length",0, false /* optional value */ );

}

/** Rescale all the parameters for a new camera resolution (it raises an exception if the aspect ratio is modified, which is not permitted).
  */
void TCamera::scaleToResolution(unsigned int new_ncols, unsigned int new_nrows)
{
        if (ncols == new_ncols && nrows == new_nrows)
                return; // already done

        ASSERT_(new_nrows>0 && new_ncols>0)

        const double prev_aspect_ratio = ncols/double(nrows);
        const double new_aspect_ratio  = new_ncols/double(new_nrows);

        ASSERTMSG_(std::abs(prev_aspect_ratio-new_aspect_ratio)<1e-3, "TCamera: Trying to scale camera parameters for a resolution of different aspect ratio." )

        const double K = new_ncols / double(ncols);

        ncols = new_ncols;
        nrows = new_nrows;

        // fx fy cx cy
        intrinsicParams(0,0)*=K;
        intrinsicParams(1,1)*=K;
        intrinsicParams(0,2)*=K;
        intrinsicParams(1,2)*=K;

        // distortion params: unmodified.
}

bool mrpt::utils::operator ==(const mrpt::utils::TCamera& a, const mrpt::utils::TCamera& b)
{
        return
                a.ncols==b.ncols &&
                a.nrows==b.nrows &&
                a.intrinsicParams==b.intrinsicParams &&
                a.dist==b.dist &&
                a.focalLengthMeters==b.focalLengthMeters;
}
bool mrpt::utils::operator !=(const mrpt::utils::TCamera& a, const mrpt::utils::TCamera& b)
{
        return !(a==b);
}