PDFHistogram2D.cpp

#include "PDFHistogram2D.h"

namespace DirectGraphicalModels
{
// Constructor
CPDFHistogram2D::CPDFHistogram2D(void) : IPDF()
{ 
    memset(m_data, 0, 256 * 256 * sizeof(long)); 
}

// Destructor
CPDFHistogram2D::~CPDFHistogram2D(void)
{ }

void CPDFHistogram2D::reset(void)
{ 
    memset(m_data, 0, 256 * 256 * sizeof(long)); 
    m_nPoints = 0;
}

void CPDFHistogram2D::addPoint(Scalar point)
{
    byte x = static_cast<byte>(MIN(255, MAX(0, point[0])));
    byte y = static_cast<byte>(MIN(255, MAX(0, point[1])));
    m_data[x][y]++;
    m_nPoints++;
}

double CPDFHistogram2D::getDensity(Scalar point)
{
    byte x = static_cast<byte>(MIN(255, MAX(0, point[0])));
    byte y = static_cast<byte>(MIN(255, MAX(0, point[1])));
    return m_nPoints ? static_cast<double>(m_data[x][y]) / m_nPoints : 0;
}

void CPDFHistogram2D::smooth(int nIt)
{
    long tmp[256][256];
    for (int iter = 0; iter < nIt; iter++) {
        memcpy(tmp, m_data, 256 * 256 * sizeof(long));
        for (int x = 1; x < 255; x++)
            for (int y = 1; y < 255; y++)
                m_data[x][y] = static_cast<long>(0.125 * (tmp[x][y-1] + tmp[x-1][y] + 4 * tmp[x][y] + tmp[x+1][y] + tmp[x][y+1]));
    } // iterations
}

void CPDFHistogram2D::saveFile(FILE *pFile) const
{
    fwrite(&m_data, sizeof(long), 256 * 256, pFile);
    fwrite(&m_nPoints, sizeof(long), 1, pFile);
}

void CPDFHistogram2D::loadFile(FILE *pFile)
{
    fread(&m_data, sizeof(long), 256 * 256, pFile);
    fread(&m_nPoints, sizeof(long), 1, pFile);
}
}