distrans.py sample added

diff --git a/samples/python2/common.py b/samples/python2/common.py
index eef5b80..e5eefd4 100644 (file)
--- a/samples/python2/common.py
+++ b/samples/python2/common.py
@@ -83,3 +83,29 @@ class Sketcher:
             self.show()\r
         else:\r
             self.prev_pt = None\r
+\r
+\r
+# palette data from matplotlib/_cm.py\r
+_jet_data =   {'red':   ((0., 0, 0), (0.35, 0, 0), (0.66, 1, 1), (0.89,1, 1),\r
+                         (1, 0.5, 0.5)),\r
+               'green': ((0., 0, 0), (0.125,0, 0), (0.375,1, 1), (0.64,1, 1),\r
+                         (0.91,0,0), (1, 0, 0)),\r
+               'blue':  ((0., 0.5, 0.5), (0.11, 1, 1), (0.34, 1, 1), (0.65,0, 0),\r
+                         (1, 0, 0))}\r
+\r
+cmap_data = { 'jet' : _jet_data }\r
+\r
+def make_cmap(name, n=256):\r
+    data = cmap_data[name]\r
+    xs = np.linspace(0.0, 1.0, n)\r
+    channels = []\r
+    eps = 1e-6\r
+    for ch_name in ['blue', 'green', 'red']:\r
+        ch_data = data[ch_name]\r
+        xp, yp = [], []\r
+        for x, y1, y2 in ch_data:\r
+            xp += [x, x+eps]\r
+            yp += [y1, y2]\r
+        ch = np.interp(xs, xp, yp)\r
+        channels.append(ch)\r
+    return np.uint8(np.array(channels).T*255)\r

diff --git a/samples/python2/distrans.py b/samples/python2/distrans.py
new file mode 100644 (file)
index 0000000..dc3fd94
--- /dev/null
+++ b/samples/python2/distrans.py
@@ -0,0 +1,55 @@
+import numpy as np\r
+import cv2, cv\r
+from common import make_cmap\r
+\r
+help_message = '''USAGE: distrans.py [<image>]\r
+\r
+Keys:\r
+  ESC   - exit\r
+  v     - toggle voronoi mode\r
+'''\r
+\r
+if __name__ == '__main__':\r
+    import sys\r
+    try: fn = sys.argv[1]\r
+    except: fn = '../cpp/fruits.jpg'\r
+    print help_message\r
+\r
+    img = cv2.imread(fn, 0)\r
+    cm = make_cmap('jet')\r
+    need_update = True\r
+    voronoi = False\r
+\r
+    def update(dummy=None):\r
+        global need_update\r
+        need_update = False\r
+        thrs = cv2.getTrackbarPos('threshold', 'distrans')\r
+        mark = cv2.Canny(img, thrs, 3*thrs)\r
+        dist, labels = cv2.distanceTransform(~mark, cv.CV_DIST_L2, 5)\r
+        if voronoi:\r
+            vis = cm[np.uint8(labels)]\r
+        else:\r
+            vis = cm[np.uint8(dist*2)]\r
+        vis[mark != 0] = 255\r
+        cv2.imshow('distrans', vis)\r
+\r
+    def invalidate(dummy=None):\r
+        global need_update\r
+        need_update = True\r
+\r
+    cv2.namedWindow('distrans') \r
+    cv2.createTrackbar('threshold', 'distrans', 60, 255, invalidate)\r
+    update()\r
+\r
+\r
+    while True:\r
+        ch = cv2.waitKey(50)\r
+        if ch == 27:\r
+            break\r
+        if ch == ord('v'):\r
+            voronoi = not voronoi\r
+            print 'showing', ['distance', 'voronoi'][voronoi]\r
+            update()\r
+        if need_update:\r
+            update()\r
+      \r

diff --git a/samples/python2/edge.py b/samples/python2/edge.py
index c2482ae..2eea855 100644 (file)
--- a/samples/python2/edge.py
+++ b/samples/python2/edge.py
@@ -18,7 +18,7 @@ while True:
     gray = cv2.cvtColor(img, cv.CV_BGR2GRAY)\r
     thrs1 = cv2.getTrackbarPos('thrs1', 'edge')\r
     thrs2 = cv2.getTrackbarPos('thrs2', 'edge')\r
-    edge = cv2.canny(gray, thrs1, thrs2, apertureSize=5)\r
+    edge = cv2.Canny(gray, thrs1, thrs2, apertureSize=5)\r
     vis = img.copy()\r
     vis /= 2\r
     vis[edge != 0] = (0, 255, 0)\r