pixeldup.m

冈萨雷斯的经典教材数字图像处理的matlab版源代码

function B = pixeldup(A, m, n)
%PIXELDUP Duplicates pixels of an image in both directions.
%   B = PIXELDUP(A, M, N) duplicates each pixel of A M times in the
%   vertical direction and N times in the horizontal direction.
%   Parameters M and N must be integers.  If N is not included, it
%   defaults to M.

%   Copyright 2002-2004 R. C. Gonzalez, R. E. Woods, & S. L. Eddins
%   Digital Image Processing Using MATLAB, Prentice-Hall, 2004
%   $Revision: 1.4 $  $Date: 2003/06/14 16:29:54 $

% Check inputs.
if nargin < 2 
   error('At least two inputs are required.'); 
end
if nargin == 2 
   n = m; 
end

% Generate a vector with elements 1:size(A, 1).
u = 1:size(A, 1);

% Duplicate each element of the vector m times.
m = round(m); % Protect against nonintergers.
u = u(ones(1, m), :);
u = u(:);

% Now repeat for the other direction.
v = 1:size(A, 2);
n = round(n);
v = v(ones(1, n), :);
v = v(:);
B = A(u, v);