diff toolboxes/FullBNT-1.0.7/KPMtools/imresizeAspect.m @ 0:e9a9cd732c1e tip

first hg version after svn
author wolffd
date Tue, 10 Feb 2015 15:05:51 +0000
parents
children
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/toolboxes/FullBNT-1.0.7/KPMtools/imresizeAspect.m	Tue Feb 10 15:05:51 2015 +0000
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+function img = imresizeAspect(img, maxSize)
+% function img = imresizeAspect(img, maxSize)
+% If image is larger than max size, reduce size, preserving aspect ratio of input.
+%
+% If size(input) = [y x] and maxSize = [yy xx],
+% then size(output) is given by the following (where a=y/x)
+%  if y<yy & x<xx  then [y x] 
+%  else if a<1 then [a*xx xx] 
+%  else [yy yy/a] 
+
+% For why we use bilinear,
+% See http://nickyguides.digital-digest.com/bilinear-vs-bicubic.htm
+
+if isempty(maxSize), return; end
+
+[y x c] = size(img);
+a= y/x;
+yy = maxSize(1); xx = maxSize(2); 
+if y <= yy & x <= xx
+  % no-op
+else
+  if a < 1
+    img = imresize(img, ceil([a*xx xx]), 'bilinear');
+  else
+    img = imresize(img, ceil([yy yy/a]), 'bilinear');
+  end
+  fprintf('resizing from %dx%d to %dx%d\n', y, x, size(img,1), size(img,2));
+end
+
+
+%test
+if 0
+  maxSize = [240 320];
+  %img = imread('C:\Images\Wearables\web_static_office\8.jpg'); 
+  %img = imread('C:\Images\Wearables\web_static_office\billandkirsten.jpg'); 
+  %img = imread('C:\Images\Wearables\web_static_street_april\p5.jpg'); 
+  img = imread('C:\Images\Wearables\Database_static_street\art11.jpg'); 
+  img2 = imresizeAspect(img, maxSize);
+  figure(1); clf; imshow(img)
+  figure(2); clf; imshow(img2)
+  fprintf('%dx%d (%5.3f) to %dx%d (%5.3f)\n', ...
+	  size(img,1), size(img,2), size(img,1)/size(img,2), ...
+	  size(img2,1), size(img2,2), size(img2,1)/size(img2,2));
+end