Resize image without change aspect ratio of that image

I have leaf image which got by scan real leaf. I want to reduce the dimensions of that image without change aspect ratio of the image. And it is not necessary to fit to given dimension. It can be used padding also. Simply I want to reduce image size to 256*256 and doesn't change aspect ratio of it. how to do this?

Answer 1

[Walter Roberson]

%figure out the pad value to pad to white
if isinteger(YourImage)
   pad = intmax(class(YourImage));
else
   pad = 1;   %white for floating point is 1.0
end

%figure out which dimension is longer and rescale that to be the 256
%and pad the shorter one to 256
[r, c, ~] = size(YourImage)
if r > c
  newImage = imresize(YourImage, 256 / r);
  NewImage(:, end+1 : 256, :) = pad;
elseif c > r
  newImage = imresize(YourImage, 256 / c);
  NewImage(end+1 : 256, :, :) = pad;
else
  newImage = imresize(YourImage, [256, 256]);
end

[Image Analyst]

There is also a padarray() function that can be used.

[Malan Jayanka]

Thank you sir, I will try this and if there are any problems I will ask from you sir