Image Processing
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Hi 2 all I have 16x16 image i want to convert this to 128x128 image (that means for every 16 bit it must replicate to 8x8 of this same bit value) Please clarify this Thx in advance
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Accepted Answer
Image Analyst
on 20 Aug 2011
Another way to do it, using the Image Processing Toolbox:
m128 = imresize(m16, 8, 'nearest');
2 Comments
Sean de Wolski
on 22 Aug 2011
It's the name of the image variable that will be 128x128, hence the descriptive numbering.
More Answers (2)
Sean de Wolski
on 20 Aug 2011
New_Image = kron(your_image,ones(8));
Kronecker Tensor Product
3 Comments
Sean de Wolski
on 22 Aug 2011
It's probably just dirt from the trail. I'll get a bigger picture! And yes, she got Firedog 4.2.
Vivek Bhadouria
on 22 Aug 2011
Use this piece of code
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% This program is used to zoom or shrink an image
% Input:image B3: gray-image or RGB image
% p: ratio, zooming (p>1), shrink(p<1)
% m: mode; =0:(default) nearest neighbor interpolation
% =1: Bilinear interpolation
% =2: Bicubic interpolation
% Output: image A3 % A3 = imageresize(B3,p,m);
%Vivek Singh Bhadouria, NIT-Agartala
%India, 9 August 2011, 01:05 AM
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
function A3 = imageresize(B3,p,m)
B3=im2double(B3);
error(nargchk(2, 3, nargin, 'struct'));
if nargin < 3, m = 0; end
dimB = length(size(B3));
if dimB== 2 % GRAY-IMAGE INPUT:
A3 = gray_resize(B3,p,m);
elseif dimB== 3 % COLOR RGB-IMAGE INPUT:
AR = gray_resize(B3(:,:,1),p,m);
AG = gray_resize(B3(:,:,2),p,m);
AB = gray_resize(B3(:,:,3),p,m);
A3 = zeros([size(AR) 3]);
A3(:,:,1) = AR;
A3(:,:,2) = AG;
A3(:,:,3) = AB;
else
error('Improper input image');
end
%**************************************************%
%==================================================%
% Sub-Function: Resize a gray-image
% Same input argument with imageresize()
function A = gray_resize(B,p,m)
% Initialize new-grid and output
[N,M] = size(B);
xp = 1:1/p:N+1/p; yp = 1:1/p:M+1/p;
A = zeros(length(xp),length(yp));
% Symmetric Padding
npad = 3;
B = sym_pad(B,npad);
switch m
case 0 % Nearest neighbor interpolation
U = round(xp); V = round(yp);
U(find(U<1)) = 1; V(find(V<1)) = 1;
U(find(U>N)) = N; V(find(V>M)) = M;
A = B(U+npad,V+npad);
case 1 % Bilinear interpolation
% Floor of (xp,yp)
xf = floor(xp); yf = floor(yp);
% Distance to top-left neighbors
[XF,YF] = ndgrid(xf,yf);
[XP,YP] = ndgrid(xp,yp);
u = XP - XF; v = YP - YF;
% Change xf, yf for new padding image
xf = xf + npad; yf = yf + npad;
% Interpolation
A = (1-u).*(1-v).*B(xf,yf) + ...
(1-u).*v .*B(xf,yf+1) + ...
u .*(1-v) .*B(xf+1,yf) + ...
u .*v .*B(xf+1,yf+1);
case 2
% Floor of (xp,yp)
xf = floor(xp);yf = floor(yp);
% Distance to top-left neighbors
[XF,YF] = ndgrid(xf,yf);
[XP,YP] = ndgrid(xp,yp);
u = XP - XF; v = YP - YF;
% Change xf, yf for new padding image
xf = xf + npad; yf = yf + npad;
% Interpolation: 16 neighbors
for i = -1:2
for j = -1:2
if i==-1, sgi = -1; else sgi = 1; end
if j==-1, sgj = -1; else sgj = 1; end
A = A + mex_hat(sgi*(i-u)).*mex_hat(sgj*(j-v)).*B(xf+i,yf+j);
end
end
otherwise
error('Undefined Interpolation method');
end
%**************************************************%
%==================================================%
% Sub-Function: Mexican-hat kernel
function hx = mex_hat(x)
hx = zeros(size(x));
x = abs(x);
ind1 = find(x<=1); ind2 = find(x>1 & x<=2);
hx(ind1) = 1 - 2*x(ind1).^2 + x(ind1).^3;
hx(ind2) = 4 - 8*x(ind2) + 5*x(ind2).^2 - x(ind2).^3;
% END of sub-function
%==================================================%
% Sub-Function: symmetric padding, by default 2 pixels
% Input: gray image
function Bp = sym_pad(B,n)
Bp = zeros(size(B)+2*n);
Bp(n+1:end-n,n+1:end-n) = B;
% Padding symmetrically 4 boundaries
Bp(n:-1:1,n+1:end-n) = B(1:n,:);
Bp(n+1:end-n,n:-1:1) = B(:,1:n);
Bp(end-n+1:end,n+1:end-n) = B(end:-1:end-n+1,:);
Bp(n+1:end-n,end-n+1:end) = B(:,end:-1:end-n+1);
% END of sub-function
%==================================================%
HAPPY TO HELP FOR SCIENTIFIC NOBLE CAUSE
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