--- /dev/null
+#! /usr/bin/env python
+
+print "OpenCV Python version of lkdemo"
+
+import sys
+
+# import the necessary things for OpenCV
+from opencv import cv
+from opencv import highgui
+
+#############################################################################
+# 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 default parameters
+quality = 0.01
+min_distance = 10
+
+#############################################################################
+# 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 event == highgui.CV_EVENT_LBUTTONDOWN:
+ # user has click, so memorize it
+ pt = cv.cvPoint (x, y)
+ add_remove_pt = True
+
+#############################################################################
+# so, here is the main part of the program
+
+if __name__ == '__main__':
+
+ try:
+ # try to get the device number from the command line
+ device = int (sys.argv [1])
+
+ # got it ! so remove it from the arguments
+ del sys.argv [1]
+ except (IndexError, ValueError):
+ # no device number on the command line, assume we want the 1st device
+ device = 0
+
+ if len (sys.argv) == 1:
+ # no argument on the command line, try to use the camera
+ capture = highgui.cvCreateCameraCapture (device)
+
+ else:
+ # we have an argument on the command line,
+ # we can assume this is a file name, so open it
+ capture = highgui.cvCreateFileCapture (sys.argv [1])
+
+ # check that capture device is OK
+ if not capture:
+ print "Error opening capture device"
+ 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" \
+ "To add/remove a feature point click it\n"
+
+ # first, create the necessary windows
+ highgui.cvNamedWindow ('LkDemo', highgui.CV_WINDOW_AUTOSIZE)
+
+ # register the mouse callback
+ highgui.cvSetMouseCallback ('LkDemo', on_mouse, None)
+
+ while 1:
+ # do forever
+
+ # 1. capture the current image
+ frame = highgui.cvQueryFrame (capture)
+ if frame is None:
+ # no image captured... end the processing
+ break
+
+ if image is None:
+ # create the images we need
+ image = cv.cvCreateImage (cv.cvGetSize (frame), 8, 3)
+ grey = cv.cvCreateImage (cv.cvGetSize (frame), 8, 1)
+ prev_grey = cv.cvCreateImage (cv.cvGetSize (frame), 8, 1)
+ pyramid = cv.cvCreateImage (cv.cvGetSize (frame), 8, 1)
+ prev_pyramid = cv.cvCreateImage (cv.cvGetSize (frame), 8, 1)
+ eig = cv.cvCreateImage (cv.cvGetSize (frame), cv.IPL_DEPTH_32F, 1)
+ temp = cv.cvCreateImage (cv.cvGetSize (frame), cv.IPL_DEPTH_32F, 1)
+ points = [[], []]
+
+ # copy the frame, so we can draw on it
+ cv.cvCopy (frame, image)
+
+ # create a grey version of the image
+ cv.cvCvtColor (image, grey, cv.CV_BGR2GRAY)
+
+ if night_mode:
+ # night mode: only display the points
+ cv.cvSetZero (image)
+
+ if need_to_init:
+ # we want to search all the good points
+ # create the wanted images
+
+ # search the good points
+ points [1] = cv.cvGoodFeaturesToTrack (
+ grey, eig, temp,
+ MAX_COUNT,
+ quality, min_distance, None, 3, 0, 0.04)
+
+ # refine the corner locations
+ cv.cvFindCornerSubPix (
+ grey,
+ points [1],
+ cv.cvSize (win_size, win_size), cv.cvSize (-1, -1),
+ cv.cvTermCriteria (cv.CV_TERMCRIT_ITER | cv.CV_TERMCRIT_EPS,
+ 20, 0.03))
+
+ elif len (points [0]) > 0:
+ # we have points, so display them
+
+ # calculate the optical flow
+ [points [1], status], something = cv.cvCalcOpticalFlowPyrLK (
+ prev_grey, grey, prev_pyramid, pyramid,
+ points [0], len (points [0]),
+ (win_size, win_size), 3,
+ len (points [0]),
+ None,
+ cv.cvTermCriteria (cv.CV_TERMCRIT_ITER|cv.CV_TERMCRIT_EPS,
+ 20, 0.03),
+ flags)
+
+ # initializations
+ point_counter = -1
+ new_points = []
+
+ for the_point in points [1]:
+ # go trough all the points
+
+ # increment the counter
+ point_counter += 1
+
+ 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
+ dx = pt.x - the_point.x
+ dy = pt.y - the_point.y
+ if dx * dx + dy * dy <= 25:
+ # too close
+ add_remove_pt = 0
+ continue
+
+ if not status [point_counter]:
+ # we will disable this point
+ continue
+
+ # this point is a correct point
+ new_points.append (the_point)
+
+ # draw the current point
+ cv.cvCircle (image,
+ cv.cvPointFrom32f(the_point),
+ 3, cv.cvScalar (0, 255, 0, 0),
+ -1, 8, 0)
+
+ # set back the points we keep
+ points [1] = new_points
+
+ if add_remove_pt:
+ # we want to add a point
+ points [1].append (cv.cvPointTo32f (pt))
+
+ # refine the corner locations
+ points [1][-1] = cv.cvFindCornerSubPix (
+ grey,
+ [points [1][-1]],
+ cv.cvSize (win_size, win_size), cv.cvSize (-1, -1),
+ cv.cvTermCriteria (cv.CV_TERMCRIT_ITER | cv.CV_TERMCRIT_EPS,
+ 20, 0.03))[0]
+
+ # we are no more in "add_remove_pt" mode
+ add_remove_pt = False
+
+ # swapping
+ prev_grey, grey = grey, prev_grey
+ prev_pyramid, pyramid = pyramid, prev_pyramid
+ points [0], points [1] = points [1], points [0]
+ need_to_init = False
+
+ # we can now display the image
+ highgui.cvShowImage ('LkDemo', image)
+
+ # handle events
+ c = highgui.cvWaitKey (10)
+
+ if c == '\x1b':
+ # user has press the ESC key, so exit
+ break
+
+ # processing depending on the character
+ if c in ['r', 'R']:
+ need_to_init = True
+ elif c in ['c', 'C']:
+ points = [[], []]
+ elif c in ['n', 'N']:
+ night_mode = not night_mode
projects / opencv / blobdiff