PDFHistogram.cpp

#include "PDFHistogram.h"

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

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

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

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

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

void CPDFHistogram::smooth(int nIt)
{
    long tmp[256];
    for (int iter = 0; iter < nIt; iter++) {
        memcpy(tmp, m_data, 256 * sizeof(long));
        for (int i = 1; i < 255; i++) m_data[i] = static_cast<long>(0.25 * (tmp[i-1] + 2*tmp[i] + tmp[i+1]));
    } // iterations
}

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

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

}