MeanFilter.cpp

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// ****************************************************************************
// This file is part of the Integrating Vision Toolkit (IVT).
//
// The IVT is maintained by the Karlsruhe Institute of Technology (KIT)
// (www.kit.edu) in cooperation with the company Keyetech (www.keyetech.de).
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// ****************************************************************************
// ****************************************************************************
// Filename:  MeanFilter.cpp
// Author:    Pedram Azad
// Date:      2006
// ****************************************************************************


// ****************************************************************************
// Includes
// ****************************************************************************

#include <new> // for explicitly using correct new/delete operators on VC DSPs

#include "MeanFilter.h"

#include <stdio.h>



// ****************************************************************************
// Constructor / Destructor
// ****************************************************************************

CMeanFilter::CMeanFilter(int nKernelSize)
{
        m_pValues = 0;
        m_nPosition = 0;
        m_nElementsFilled = 0;
        m_nKernelSize = 0;
        
        SetKernelSize(nKernelSize);
}

CMeanFilter::~CMeanFilter()
{
        if (m_pValues)
                delete [] m_pValues;
}


// ****************************************************************************
// Methods
// ****************************************************************************

void CMeanFilter::SetKernelSize(int nKernelSize)
{
        if (nKernelSize <= 0)
        {
                printf("error: nKernelSize must be greater 0 for CMeanFilter::SetKernelSize\n");
                return;
        }
        
        m_nKernelSize = nKernelSize;
        
        if (m_pValues)
                delete [] m_pValues;
        
        m_pValues = new float[nKernelSize];
        
        Reset();
}

void CMeanFilter::Reset()
{
        for (int i = 0; i < m_nKernelSize; i++)
                m_pValues[i] = 0.0f; // this is not really necessary...

        m_nPosition = 0;
        m_nElementsFilled = 0;
}

float CMeanFilter::Filter(float x)
{
        if (m_nKernelSize <= 0)
        {
                printf("error: CMeanFilter::Filter called, but m_nKernelSize is invalid (%i)\n", m_nKernelSize);
                return x;
        }

        m_pValues[m_nPosition++ % m_nKernelSize] = x;
        if (m_nElementsFilled < m_nKernelSize)
                m_nElementsFilled++;
        
        float sum = 0.0f;
        for (int i = 0; i < m_nElementsFilled; i++)
                sum += m_pValues[i];

        return sum / m_nElementsFilled;
}