MATLAB Examples

## Contents

```function demoImMaxFeretDiameter(varargin) ```
```%DEMOIMORIENTEDBOX Demo file for computing maximum Feret diameters % % Usage: % demoImMaxFeretDiameter % The demo runs automatically. A basic segmentation is performed on a % demo image, then maximum Feret diameters are computed for each particle % and displayed on the original image. % % Example % demoImMaxFeretDiameter % % See also % demoImOrientedBox, imMaxFeretDiameter % % ------ % Author: David Legland % e-mail: david.legland@grignon.inra.fr % Created: 2011-05-09, using Matlab 7.9.0.529 (R2009b) % Copyright 2011 INRA - Cepia Software Platform. ```

## Image segmentation

```% read image img = imread('rice.png'); figure(1); clf; imshow(img); % compute background bg = imopen(img, ones(30, 30)); img2 = img - bg; figure(2); clf; imshow(img2); % display histogram, to identify the threshold value figure(3); clf; imHistogram(img2); % image binarisation, and remove particles touching border bin = img2 > 50; bin = imclearborder(bin, 4); imshow(bin); % compute image labels, using minimal connectivity lbl = bwlabel(bin, 4); nLabels = max(lbl(:)); % display label image rgb = label2rgb(lbl, jet(nLabels), 'w', 'shuffle'); figure(4); clf; imshow(rgb); ```

## Compute enclosing oriented boxes

```% compute diameters with corresponding angles [diams thetas] = imMaxFeretDiameter(lbl); % also compute centroids centros = imCentroid(lbl); % overlay result on image hold on; drawCenteredEdge([centros diams thetas], 'linewidth', 2, 'color', 'k'); ```