Changeset 14580

Timestamp:

04/15/13 14:23:24 (12 years ago)

Author:

Eric.Larour

Message:

CHG: some mods on morphological routines

Location:

issm/trunk-jpl/src/m/morphological

Files:

• aggregation.m (modified) (2 diffs)
• nunataks.m (added)
• vectorialize.m (modified) (1 diff)

issm/trunk-jpl/src/m/morphological/aggregation.m

@@ -1 @@
-function mask=aggregation(mask,windowsize,threshhold)
-%congrid algorithm using windowsize pixel neighboors.
+function [mask,varargout]=aggregation(mask,windowsize,threshhold,varargin)
+%AGGREGATION - aggregation of an image to a lower sized image
+% 
+%  mask is an image of arbitrary size, format binary, with values 1 for foreground, and 0 for background
+%  mask is first convoluted with a square matrix of size windowsize (where windowsize is an even number), 
+%       it is then filtered according to the threshhold value, and finally subsampled using 1/windowsize as 
+%       sample scaling. 
+%  x,y can be provided as optional arguments, as coordinates of the center points of the mask. aggregation will 
+%       then return subsampled x,y arguments in output.
+% 
+%  Usage:   mask2=aggregation(mask,7,7^2/2);
+%           [mask2,x2,y2]=aggregation(mask,7,7^2,x,y];
+%
+%  See also CLOSING, OPENING, DILATION, EROSION
 
-%check on windowsize
+%check input arguments  %{{{
+%even windowsize
 if mod(windowsize,2)==0,
         error('windowsize should be an even number');
 end
 
-%convolve: 
+%check on presence of varargin: 
+optional=0;
+if nargin>3,
+        if nargin~=5,
+                help aggregation;
+                error('wrong number of optional arguments specified');
+        else
+                optional=1;
+                x=varargin{1};
+                y=varargin{2};
+        end
+end
+
+%check on presence of varargout: 
+if optional,
+        if nargout~=3,
+                help aggregation;
+                error('wrong number of optional output arguments specified');
+        end
+end
+%}}}
+
+%convolve mask
 matrix=ones(windowsize,windowsize); 
+mask=filter2(matrix,mask,'same');
 
-%convolve mask: 
-mask=filter2(matrix,double(mask),'same');
-
+%apply threshhold
 pos=find(mask>threshhold); 
 pos2=find(mask<=threshhold); 
@@ -18 +52 @@
 mask(pos2)=0;
 
-%now subsample: 
+%mask has been transformed into double format from the filter2  operation. Bring back to binary. 
+mask=logical(mask);
+
+%subsample: 
 s=size(mask);
 mask=mask(1:windowsize:s(1),1:windowsize:s(2));
+
+if optional,
+        s=size(mask);
+        varargout{1}=x(1:windowsize:s(2));
+        varargout{2}=y(1:windowsize:s(1));
+end

issm/trunk-jpl/src/m/morphological/vectorialize.m

@@ -1 +1 @@
 function contours=vectorialize(mask,connectivity);
 
-        vec=bwboundaries(mask,8);
+        vec=bwboundaries(mask,connectivity);
         
         contours=struct([]);