rename findLabels.m to findRegionLabels.m

Author: dlegland

src/@Image/findLabels.m

@@ -1,6 +1,8 @@
 function labels = findLabels(obj)
 % Find unique labels in a label image.
 %
+%   Deprecated: renamed as findRegionLabels
+%
 %   output = findLabels(input)
 %
 %   Example
@@ -16,6 +18,8 @@
 % Created: 2018-07-03,    using Matlab 9.4.0.813654 (R2018a)
 % Copyright 2018 INRA - Cepia Software Platform.
 
+warning('deprecated, use ''findRegionLabels'' instead');
+
 % test special case of binary image based on image type
 if isBinaryImage(obj)
     labels = 1;

src/@Image/findRegionLabels.m

@@ -0,0 +1,58 @@
+function labels = findRegionLabels(obj)
+% Find unique region labels within a label or binary image.
+%
+%   LABELS = findRegionLabels(IMG)
+%
+%   Example
+%     img = Image.read('coins.png');
+%     bin = fillHoles(img > 100);
+%     lbl = componentLabeling(bin);
+%     labels = findRegionLabels(lbl)'
+%     labels =
+%          1     2     3     4     5     6     7     8     9    10
+%
+%   See also
+%     regionCentroids, unique
+%
+
+% ------
+% Author: David Legland
+% e-mail: david.legland@inrae.fr
+% Created: 2018-07-03,    using Matlab 9.4.0.813654 (R2018a)
+% Copyright 2018 INRA - Cepia Software Platform.
+
+% test special case of binary image based on image type
+if isBinaryImage(obj)
+    labels = 1;
+    return;
+end
+
+if ~isLabelImage(obj)
+    error('Requires a label image');
+end
+
+if isinteger(obj.Data)
+    % For integer images, iterates over possible labels
+    
+    % allocate memory
+    maxLabel = double(max(obj.Data(:)));
+    labels = zeros(maxLabel, 1);
+    
+    % iterate over possible labels
+    nLabels = 0;
+    for i = 1:maxLabel
+        if any(obj.Data(:) == i)
+            nLabels = nLabels + 1;
+            labels(nLabels) = i;
+        end
+    end
+    
+    % trim label array
+    labels = labels(1:nLabels);
+    
+else
+    % use generic processing for floating-point images
+    labels = unique(obj.Data(:));
+    labels(labels==0) = [];
+end
+    

tests/image/test_findRegionLabels.m

@@ -0,0 +1,34 @@
+function tests = test_findRegionLabels
+% Test suite for the file findRegionLabels.
+%
+%   Test suite for the file findRegionLabels
+%
+%   Example
+%   test_findRegionLabels
+%
+%   See also
+%     findRegionLabels
+
+% ------
+% Author: David Legland
+% e-mail: david.legland@inrae.fr
+% Created: 2021-02-02,    using Matlab 9.8.0.1323502 (R2020a)
+% Copyright 2021 INRAE - BIA-BIBS.
+
+tests = functiontests(localfunctions);
+
+function test_Simple(testCase) %#ok<*DEFNU>
+% Test call of function without argument.
+
+data = zeros([10 6], 'uint8');
+data(1:2,1:2) = 3;
+data(4:8,1:2) = 4;
+data(2:5,4:5) = 7;
+data(7:10,5:6) = 8;
+img = Image('Data', data, 'Type', 'Label');
+
+labels = findRegionLabels(img);
+
+assertEqual(testCase, labels, [3 4 7 8]');
+
+