Kontur=bwcontour(I)

function Kontur=bwcontour(I)

figure;
%----------------------
K=contour (I, [1,1]);
%----------------------
% contour cordinates
x=[];
y=[];
%first part
idx=1; % showing the number of points
Konturlaenge=K(2,idx);


sum_Konturlaenge=Konturlaenge+0;
while (sum_Konturlaenge) < size(K,2)

        x=[x K(1,idx+1:idx+Konturlaenge)];
        y=[y K(2,idx+1:idx+Konturlaenge)];
        idx=idx+Konturlaenge+1;

    if idx< size(K,2)
        Konturlaenge=K(2,idx);
    end
    sum_Konturlaenge=Konturlaenge+sum_Konturlaenge+1;
end

Kontur=zeros(size(I,1),size(I,2));
for i=1:size(x,2)
    Kontur(y(i),x(i))=1;
end
figure;imshow(Kontur)