zoomwithoutinterpolation(I)

% function : zoom without interpolation
% input    : n X m Gray Image
% output   : 2n X 2m Gray Image
%--------------------------------------

function R = zoomwithoutinterpolation(I)
  [n,m] = size(I);
  for row = 1 : n
    for col = 1 : m
      R(row+row-1 : row+row , col+col-1 : col+col ) = I(row, col);
    end
  end
return