cxImageDefaultTFGenerator.cpp

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/*=========================================================================
This file is part of CustusX, an Image Guided Therapy Application.

Copyright (c) 2008-2014, SINTEF Department of Medical Technology
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#include "cxImageDefaultTFGenerator.h"

#include "vtkImageData.h"
#include "cxImage.h"
#include "cxImageLUT2D.h"
#include "cxImageTF3D.h"
#include "math.h"

namespace cx
{

ImageDefaultTFGenerator::ImageDefaultTFGenerator(ImagePtr image) : mImage(image)
{

}

void ImageDefaultTFGenerator::resetShading()
{
        // add shading for known preoperative modalities
        if (mImage->getModality().contains("CT") || mImage->getModality().contains("MR"))
                mImage->setShadingOn(true);
}

ImageLUT2DPtr ImageDefaultTFGenerator::generate2DTFPreset()
{
        ImageLUT2DPtr tf(new ImageLUT2D());

        double_pair fullRange = this->getFullScalarRange();
        double_pair range = this->guessInitialScalarRange();
        double smin = range.first;
        double smax = range.second;

        IntIntMap opacity;
        opacity[fullRange.first - 1] = 0;
        opacity[fullRange.first] = 255;
        tf->resetAlpha(opacity);

        ColorMap colors;
        colors[smin] = QColor(Qt::black);
        colors[smax] = QColor(Qt::white);
        tf->resetColor(colors);

        return tf;
}

namespace
{
int myround(double val)
{
        return int(val+0.5);
}
}

ImageTF3DPtr ImageDefaultTFGenerator::generate3DTFPreset()
{
        ImageTF3DPtr tf(new ImageTF3D());

        double_pair range = this->guessInitialScalarRange();

        double smin = range.first;
        double smax = range.second;
        double srange = smax - smin;

        IntIntMap opacity;
        // Note the ordering: add in descending order to ensure zero is
        // always written into smin, also for binary volumes
        // Round is required for binary volumes.
        opacity[smin + myround(0.5*srange)] = 255;
        opacity[smin + myround(0.3*srange)] = 255.0 * 0.7;
        opacity[smin + myround(0.1*srange)] = 0;
        tf->resetAlpha(opacity);

        ColorMap colors;
        colors[smin] = QColor(Qt::black);
        colors[smax] = QColor(Qt::white);
        tf->resetColor(colors);

        return tf;
}

bool ImageDefaultTFGenerator::hasValidInitialWindow() const
{
        return mImage->getInitialWindowWidth()>0;
}

double_pair ImageDefaultTFGenerator::guessInitialScalarRange() const
{
        double_pair srange = this->getFullScalarRange();

        if (this->hasValidInitialWindow())
        {
                srange = this->getInitialWindowRange();
        }
        // no initial window: add heuristics for each modality
        if (!this->hasValidInitialWindow())
        {
                if (this->isUnsignedChar())
                {
                        srange.first = 0;
                        srange.second = 255;

                        if (this->looksLikeBinaryImage())
                        {
                                srange.first = 0;
                                srange.second = 1;
                        }
                }
                if (mImage->getModality().contains("CT"))
                {
                        srange = this->guessCTRange();
                }
                if (mImage->getModality().contains("MR"))
                {
                        srange = this->guessMRRange();
                }
        }

        srange = this->ensureNonZeroRoundedRange(srange);
        return srange;
}

bool ImageDefaultTFGenerator::isUnsignedChar() const
{
        return mImage->getBaseVtkImageData()->GetScalarType() == VTK_UNSIGNED_CHAR;
}

bool ImageDefaultTFGenerator::looksLikeBinaryImage() const
{
        double_pair r = this->getFullScalarRange();
        return similar(r.first, 0) && similar(r.second, 1);
}


double_pair ImageDefaultTFGenerator::ensureNonZeroRoundedRange(double_pair range) const
{
        range.first = int(range.first+0.5);
        range.second = int(range.second+0.5);
        range.second = std::max(range.second, range.first+1);
        return range;
}

double_pair ImageDefaultTFGenerator::getFullScalarRange() const
{
        double smin = mImage->getBaseVtkImageData()->GetScalarRange()[0];
        double smax = mImage->getBaseVtkImageData()->GetScalarRange()[1];
        return std::make_pair(smin, smax);
}

double_pair ImageDefaultTFGenerator::getInitialWindowRange() const
{
        double smin = mImage->getInitialWindowLevel() - mImage->getInitialWindowWidth()/2;
        double smax = mImage->getInitialWindowLevel() + mImage->getInitialWindowWidth()/2;
        return std::make_pair(smin, smax);
}

double_pair ImageDefaultTFGenerator::guessCTRange() const
{
        // signed: [-1024...3072]
        // choose a default from lung to bone, approximately.
        double smin = -500;
        double smax = 900;
        if (0 >= mImage->getMin()) // unsigned: [0..4096]
        {
                int ct_signed2unsigned = 1024;
                smin += ct_signed2unsigned;
                smax += ct_signed2unsigned;
        }
        return std::make_pair(smin, smax);
}

double_pair ImageDefaultTFGenerator::guessMRRange() const
{
        double_pair srange = this->getFullScalarRange();
        srange.second *= 0.25; // usually lots of high-intensity noise of no interest
        return srange;
}


} // namespace cx