--- a/python/cvutils.py	Fri Jun 29 16:15:13 2012 -0400
+++ b/python/cvutils.py	Mon Jul 02 23:49:39 2012 -0400
@@ -90,50 +90,67 @@
         if lastCoordinate != None and lastCoordinate >=0:
             last = min(positions.length()-1, lastCoordinate)
         for i in range(0, last-1):
-            cv2.line(img, positions[i].astuple(), positions[i+1].astuple(), color)
+            cv2.line(img, positions[i].asint().astuple(), positions[i+1].asint().astuple(), color)
 
-    def playVideo(filename):
+    def playVideo(filename, firstFrameNum = 0):
         '''Plays the video'''
         capture = cv2.VideoCapture(filename)
         if capture.isOpened():
             key = -1
-            while key!= 113: # 'q'
+            ret = True
+            frameNum = firstFrameNum
+            capture.set(cv2.cv.CV_CAP_PROP_POS_FRAMES, firstFrameNum)
+            while ret and key!= 113: # 'q'
                 ret, img = capture.read()
                 if ret:
+                    print('frame {0}'.format(frameNum))
+                    frameNum+=1
                     cv2.imshow('frame', img)
                     key = cv2.waitKey(5)
 
-    def getImagesFromVideo(filename, nImages = 1):
+    def getImagesFromVideo(filename, nImages = 1, saveImage = False):
         '''Returns nImages images from the video sequence'''
         images = []
         capture = cv2.VideoCapture(filename)
         if capture.isOpened():        
             ret = False
-            while len(images)<nImages:
+            numImg = 0
+            while numImg<nImages:
                 ret, img = capture.read()
-                while not ret:
+                i = 0
+                while not ret and i<10:
                     ret, img = capture.read()
+                    i += 1
                 if img.size>0:
-                    images.append(img)
+                    numImg +=1
+                    if saveImage:
+                        cv2.imwrite('image{0:04d}.png'.format(numImg), img)
+                    else:
+                        images.append(img)
         return images
 
-    def displayTrajectories(videoFilename, objects, homography = None):
+    def displayTrajectories(videoFilename, objects, homography = None, firstFrameNum = 0):
         '''Displays the objects overlaid frame by frame over the video '''
         capture = cv2.VideoCapture(videoFilename)
         if capture.isOpened():
             key = -1
-            frameNum = 1
-            while key!= 113: # 'q'
+            ret = True
+            frameNum = firstFrameNum
+            capture.set(cv2.cv.CV_CAP_PROP_POS_FRAMES, firstFrameNum)
+            while ret and key!= 113: # 'q'
+                print('capture')
                 ret, img = capture.read()
                 if ret:
-                    print(frameNum)
+                    print('frame {0}'.format(frameNum))
                     for obj in objects:
                         if obj.existsAtInstant(frameNum):
-                            #obj.getTimeInterval()
-                            if homography != None and obj.getFirstInstant() == frameNum:
-                                obj.projectedPositions = obj.positions.project(homography)
+                            if obj.getFirstInstant() == frameNum:
+                                if homography != None:
+                                    obj.projectedPositions = obj.positions.project(homography)
+                                else:
+                                    obj.projectedPositions = obj.positions
                             draw(img, obj.projectedPositions, cvRed, frameNum-obj.getFirstInstant())
-                            cv2.putText(img, '{0}'.format(obj.num), obj.projectedPositions[frameNum-obj.getFirstInstant()].astuple(), cv2.FONT_HERSHEY_PLAIN, 1, cvRed)
+                            cv2.putText(img, '{0}'.format(obj.num), obj.projectedPositions[frameNum-obj.getFirstInstant()].asint().astuple(), cv2.FONT_HERSHEY_PLAIN, 1, cvRed)
                     cv2.imshow('frame', img)
                     key = cv2.waitKey(50)
                     frameNum += 1