ecgdemowinmax.m

function Filtered=ecgdemowinmax(Original, WinSize)

    %initialising variables

    WinHalfSize = floor(WinSize/2);

    WinHalfSizePlus = WinHalfSize+1;

    WinSizeSpec = WinSize-1;

    FrontIterator = 1;

    WinPos = WinHalfSize;

    WinMaxPos = WinHalfSize;

    WinMax = Original(1);

    OutputIterator = 0;

   

    % Finding the postion of the largest value in window

    for LengthCounter = 0:1:WinHalfSize-1

        if Original(FrontIterator+1) > WinMax

            WinMax = Original(FrontIterator+1);

            WinMaxPos = WinHalfSizePlus + LengthCounter;

        end

        FrontIterator=FrontIterator+1;

    end

    % if the first point is the highest, set ouput 1

    if WinMaxPos == WinHalfSize

        Filtered(OutputIterator+1)=WinMax;

    else

        Filtered(OutputIterator+1)=0;

    end

    OutputIterator = OutputIterator+1;

   

    % search next half of signal

    for LengthCounter = 0:1:WinHalfSize-1

        if Original(FrontIterator+1)>WinMax

            WinMax=Original(FrontIterator+1);

            WinMaxPos=WinSizeSpec;

        else

            WinMaxPos=WinMaxPos-1;

        end

        if WinMaxPos == WinHalfSize

            Filtered(OutputIterator+1)=WinMax;

        else

            Filtered(OutputIterator+1)=0;

        end

        FrontIterator = FrontIterator+1;

        OutputIterator = OutputIterator+1;

    end

    for FrontIterator=FrontIterator:1:length(Original)-1

        if Original(FrontIterator+1)>WinMax

            WinMax=Original(FrontIterator+1);

            WinMaxPos=WinSizeSpec;

        else

            WinMaxPos=WinMaxPos-1;

            if WinMaxPos < 0

                WinIterator = FrontIterator-WinSizeSpec;

                WinMax = Original(WinIterator+1);

                WinMaxPos = 0;

                WinPos=0;

                for WinIterator = WinIterator:1:FrontIterator

                    if Original(WinIterator+1)>WinMax

                        WinMax = Original(WinIterator+1);

                        WinMaxPos = WinPos;

                    end

                    WinPos=WinPos+1;

                end

            end

        end

        if WinMaxPos==WinHalfSize

            Filtered(OutputIterator+1)=WinMax;

        else

            Filtered(OutputIterator+1)=0;

        end

        OutputIterator=OutputIterator+1;

    end

    WinIterator = WinIterator-1;

    WinMaxPos = WinMaxPos-1;

    for LengthCounter=1:1:WinHalfSizePlus-1

        if WinMaxPos<0

            WinIterator=length(Original)-WinSize+LengthCounter;

            WinMax=Original(WinIterator+1);

            WinMaxPos=0;

            WinPos=1;

            for WinIterator=WinIterator+1:1:length(Original)-1

                if Original(WinIterator+1)>WinMax

                    WinMax=Original(WinIterator+1);

                    WinMaxPos=WinPos;

                end

                WinPos=WinPos+1;

            end

        end

        if WinMaxPos==WinHalfSize

            Filtered(OutputIterator+1)=WinMax;

        else

            Filtered(OutputIterator+1)=0;

        end

        FrontIterator=FrontIterator-1;

        WinMaxPos=WinMaxPos-1;

        OutputIterator=OutputIterator+1;

    end