"atomic bomb" commit. Reorganized OpenCV directory structure

samples/python/lkdemo.py

@@ -0,0 +1,191 @@
+#! /usr/bin/env python
+
+print "OpenCV Python version of lkdemo"
+
+import sys
+
+# import the necessary things for OpenCV
+import cv
+
+#############################################################################
+# some "constants"
+
+win_size = 10
+MAX_COUNT = 500
+
+#############################################################################
+# some "global" variables
+
+image = None
+pt = None
+add_remove_pt = False
+flags = 0
+night_mode = False
+need_to_init = False
+
+#############################################################################
+# the mouse callback
+
+# the callback on the trackbar
+def on_mouse (event, x, y, flags, param):
+
+    # we will use the global pt and add_remove_pt
+    global pt
+    global add_remove_pt
+    
+    if image is None:
+        # not initialized, so skip
+        return
+
+    if image.origin != 0:
+        # different origin
+        y = image.height - y
+
+    if event == cv.CV_EVENT_LBUTTONDOWN:
+        # user has click, so memorize it
+        pt = (x, y)
+        add_remove_pt = True
+
+#############################################################################
+# so, here is the main part of the program
+
+if __name__ == '__main__':
+
+    frames = sys.argv[1:]
+    if frames == []:
+      print "usage lkdemo.py <image files>"
+      sys.exit(1)
+
+    # display a small howto use it
+    print "Hot keys: \n" \
+          "\tESC - quit the program\n" \
+          "\tr - auto-initialize tracking\n" \
+          "\tc - delete all the points\n" \
+          "\tn - switch the \"night\" mode on/off\n" \
+          "\tSPACE - next frame\n" \
+          "To add/remove a feature point click it\n"
+
+    # first, create the necessary windows
+    cv.NamedWindow ('LkDemo', cv.CV_WINDOW_AUTOSIZE)
+
+    # register the mouse callback
+    cv.SetMouseCallback ('LkDemo', on_mouse, None)
+
+    fc = 0
+    while 1:
+        # do forever
+
+        frame = cv.LoadImage(frames[fc])
+
+        if image is None:
+            # create the images we need
+            image = cv.CreateImage (cv.GetSize (frame), 8, 3)
+            image.origin = frame.origin
+            grey = cv.CreateImage (cv.GetSize (frame), 8, 1)
+            prev_grey = cv.CreateImage (cv.GetSize (frame), 8, 1)
+            pyramid = cv.CreateImage (cv.GetSize (frame), 8, 1)
+            prev_pyramid = cv.CreateImage (cv.GetSize (frame), 8, 1)
+            features = []
+
+        # copy the frame, so we can draw on it
+        cv.Copy (frame, image)
+
+        # create a grey version of the image
+        cv.CvtColor (image, grey, cv.CV_BGR2GRAY)
+
+        if night_mode:
+            # night mode: only display the points
+            cv.SetZero (image)
+
+        if need_to_init:
+            # we want to search all the good points
+
+            # create the wanted images
+            eig = cv.CreateImage (cv.GetSize (grey), 32, 1)
+            temp = cv.CreateImage (cv.GetSize (grey), 32, 1)
+
+            # the default parameters
+            quality = 0.01
+            min_distance = 10
+
+            # search the good points
+            features = cv.GoodFeaturesToTrack (
+                grey, eig, temp,
+                MAX_COUNT,
+                quality, min_distance, None, 3, 0, 0.04)
+
+            # refine the corner locations
+            features = cv.FindCornerSubPix (
+                grey,
+                features,
+                (win_size, win_size),  (-1, -1),
+                (cv.CV_TERMCRIT_ITER | cv.CV_TERMCRIT_EPS, 20, 0.03))
+
+        elif features != []:
+            # we have points, so display them
+
+            # calculate the optical flow
+            features, status, track_error = cv.CalcOpticalFlowPyrLK (
+                prev_grey, grey, prev_pyramid, pyramid,
+                features,
+                (win_size, win_size), 3,
+                (cv.CV_TERMCRIT_ITER|cv.CV_TERMCRIT_EPS, 20, 0.03),
+                flags)
+
+            # set back the points we keep
+            features = [ p for (st,p) in zip(status, features) if st]
+
+            if add_remove_pt:
+                # we have a point to add, so see if it is close to
+                # another one. If yes, don't use it
+                def ptptdist(p0, p1):
+                    dx = p0[0] - p1[0]
+                    dy = p0[1] - p1[1]
+                    return dx**2 + dy**2
+                if min([ ptptdist(pt, p) for p in features ]) < 25:
+                    # too close
+                    add_remove_pt = 0
+
+            # draw the points as green circles
+            for the_point in features:
+                cv.Circle (image, (int(the_point[0]), int(the_point[1])), 3, (0, 255, 0, 0), -1, 8, 0)
+            
+        if add_remove_pt:
+            # we want to add a point
+            # refine this corner location and append it to 'features'
+
+            features += cv.FindCornerSubPix (
+                grey,
+                [pt],
+                (win_size, win_size),  (-1, -1),
+                (cv.CV_TERMCRIT_ITER | cv.CV_TERMCRIT_EPS,
+                20, 0.03))
+            # we are no longer in "add_remove_pt" mode
+            add_remove_pt = False
+
+        # swapping
+        prev_grey, grey = grey, prev_grey
+        prev_pyramid, pyramid = pyramid, prev_pyramid
+        need_to_init = False
+        
+        # we can now display the image
+        cv.ShowImage ('LkDemo', image)
+
+        # handle events
+        c = cv.WaitKey(10) % 0x100
+
+        if c == 27:
+            # user has press the ESC key, so exit
+            break
+
+        # processing depending on the character
+        if 32 <= c and c < 128:
+          cc = chr(c).lower()
+          if cc == 'r':
+              need_to_init = True
+          elif cc == 'c':
+              features = []
+          elif cc == 'n':
+              night_mode = not night_mode
+          elif cc == ' ':
+              fc = (fc + 1) % len(frames)