Update to 2.0.0 tree from current Fremantle build

[opencv] / samples / octave / contours.m

diff --git a/samples/octave/contours.m b/samples/octave/contours.m
new file mode 100644 (file)
index 0000000..76d37e8
--- /dev/null
+++ b/samples/octave/contours.m
@@ -0,0 +1,140 @@
+#! /usr/bin/env octave
+
+printf("OpenCV Octave version of contours\n");
+
+## import the necessary things for OpenCV
+cv;
+
+
+global _SIZE;
+global _red;
+global _green;
+global _blue;
+global contours;
+
+## some default constants
+_SIZE = 500;
+_DEFAULT_LEVEL = 3;
+
+## definition of some colors
+_red = cvScalar (0, 0, 255, 0);
+_green = cvScalar (0, 255, 0, 0);
+_white = cvRealScalar (255);
+_black = cvRealScalar (0);
+
+## the callback on the trackbar, to set the level of contours we want
+## to display
+function on_trackbar (position)
+  global cv;
+  global _SIZE;
+  global _red;
+  global _green;
+  global _blue;
+  global contours;
+
+  ## create the image for putting in it the founded contours
+  contours_image = cvCreateImage (cvSize (_SIZE, _SIZE), 8, 3);
+
+  ## compute the real level of display, given the current position
+  levels = position - 3;
+
+  ## initialisation
+  _contours = contours;
+  
+  if (levels <= 0)
+    ## zero or negative value
+    ## => get to the nearest face to make it look more funny
+    _contours = contours.h_next.h_next.h_next;
+  endif
+  
+  ## first, clear the image where we will draw contours
+  cvSetZero (contours_image);
+  
+  ## draw contours in red and green
+  cvDrawContours (contours_image, _contours, _red, _green, levels, 3, cv.CV_AA, cvPoint (0, 0));
+
+  ## finally, show the image
+  cvShowImage ("contours", contours_image);
+endfunction
+
+## create the image where we want to display results
+image = cvCreateImage (cvSize (_SIZE, _SIZE), 8, 1);
+
+## start with an empty image
+cvSetZero (image);
+
+## draw the original picture
+for i=0:6-1,
+  dx = mod(i,2) * 250 - 30;
+  dy = (i / 2) * 150;
+  
+  cvEllipse (image,
+                cvPoint (dx + 150, dy + 100),
+                cvSize (100, 70),
+                0, 0, 360, _white, -1, 8, 0);
+  cvEllipse (image,
+                cvPoint (dx + 115, dy + 70),
+                cvSize (30, 20),
+                0, 0, 360, _black, -1, 8, 0);
+  cvEllipse (image,
+                cvPoint (dx + 185, dy + 70),
+                cvSize (30, 20),
+                0, 0, 360, _black, -1, 8, 0);
+  cvEllipse (image,
+                cvPoint (dx + 115, dy + 70),
+                cvSize (15, 15),
+                0, 0, 360, _white, -1, 8, 0);
+  cvEllipse (image,
+                cvPoint (dx + 185, dy + 70),
+                cvSize (15, 15),
+                0, 0, 360, _white, -1, 8, 0);
+  cvEllipse (image,
+                cvPoint (dx + 115, dy + 70),
+                cvSize (5, 5),
+                0, 0, 360, _black, -1, 8, 0);
+  cvEllipse (image,
+                cvPoint (dx + 185, dy + 70),
+                cvSize (5, 5),
+                0, 0, 360, _black, -1, 8, 0);
+  cvEllipse (image,
+                cvPoint (dx + 150, dy + 100),
+                cvSize (10, 5),
+                0, 0, 360, _black, -1, 8, 0);
+  cvEllipse (image,
+                cvPoint (dx + 150, dy + 150),
+                cvSize (40, 10),
+                0, 0, 360, _black, -1, 8, 0);
+  cvEllipse (image,
+                cvPoint (dx + 27, dy + 100),
+                cvSize (20, 35),
+                0, 0, 360, _white, -1, 8, 0);
+  cvEllipse (image,
+                cvPoint (dx + 273, dy + 100),
+                cvSize (20, 35),
+                0, 0, 360, _white, -1, 8, 0);
+endfor
+
+## create window and display the original picture in it
+cvNamedWindow ("image", 1);
+cvShowImage ("image", image);
+
+## create the storage area
+storage = cvCreateMemStorage (0);
+
+## find the contours
+[nb_contours, contours] = cvFindContours (image, storage, sizeof_CvContour, CV_RETR_TREE, CV_CHAIN_APPROX_SIMPLE, cvPoint (0,0));
+
+## comment this out if you do not want approximation
+contours = cvApproxPoly (contours, sizeof_CvContour, storage, CV_POLY_APPROX_DP, 3, 1);
+
+## create the window for the contours
+cvNamedWindow ("contours", 1);
+
+## create the trackbar, to enable the change of the displayed level
+cvCreateTrackbar ("levels+3", "contours", 3, 7, @on_trackbar);
+
+## call one time the callback, so we will have the 1st display done
+on_trackbar (_DEFAULT_LEVEL);
+
+## wait a key pressed to end
+cvWaitKey (0);