--- a/scripts/polytracktopdtv.py	Tue Mar 24 14:17:12 2015 +0100
+++ b/scripts/polytracktopdtv.py	Tue Mar 24 18:11:28 2015 +0100
@@ -35,7 +35,7 @@
     cursor.execute("SELECT name FROM sqlite_master WHERE type='table' AND name='objects_type'")
     data = cursor.fetchone()
 
-    if(data == None):
+    if(data is None):
         typeDict["0"] = "unknown"
         typeDict["1"] = "car"
         typeDict["2"] = "pedestrians"
@@ -59,7 +59,7 @@
     
     inc = 1000 #How many frame we fetch in the video at a time
 
-    if lastFrameNum != None:
+    if lastFrameNum is not None:
         delta = lastFrameNum-firstFrameNum
         if delta < inc:
             inc = delta
@@ -74,7 +74,7 @@
             time += datetime.timedelta(microseconds=deltaTimestamp*1000)
         currentIdx = currentIdx + inc
 
-        if lastFrameNum != None:            
+        if lastFrameNum is not None:            
             delta = lastFrameNum-currentIdx
             if delta < inc:
                 inc = delta        
@@ -96,15 +96,15 @@
     lastFrameNum is the last frame we want to extract (or None if we want to extract everything)
     '''
     error = False
-    if sceneFilename != None:
+    if sceneFilename is not None:
         scene = utils.SceneParameters.loadConfigFile(os.path.join(workDirname, sceneFilename))
         time = scene[sectionName].date
         inputDb = os.path.join(workDirname, scene[sectionName].databaseFilename)
         videoFile = os.path.join(workDirname, scene[sectionName].videoFilename)
 
-    if databaseFilename != None:
+    if databaseFilename is not None:
         inputDb = os.path.join(workDirname, databaseFilename)
-    if videoFilename != None:
+    if videoFilename is not None:
         videoFile = os.path.join(workDirname, videoFilename)
     # elif videoFolderExist == False:            
     #     print('No video path specified')
@@ -113,7 +113,7 @@
     videoFolderPath = os.path.join(workDirname, "videoframes/")
     fileName = sectionName
     
-    if videoFile != None:
+    if videoFile is not None:
         fps = cvutils.getFPS(videoFile)
         print('Video should run at ' + str(fps) + ' fps')
         deltaTimestamp = 1000.0/float(fps);
@@ -147,7 +147,7 @@
             zipFolder(videoFolderPath, inputZipVideoName)
         print('Zipping files...Done.')
         #We generate the structure for ZipVideo
-        if cameraCalibrationFilename != None:
+        if cameraCalibrationFilename is not None:
             calibrationFile = cameraCalibrationFilename
         else:
             calibrationFile = 'calib.json'
@@ -189,7 +189,7 @@
         #3) We read the bounding box table    
         cursor.execute("SELECT name FROM sqlite_master WHERE type='table' AND name='bounding_boxes'")
         data = cursor.fetchone()
-        if data == None:
+        if data is None:
             print('No bounding box table. Maybe it was not generated ?')
         else:
             cursor.execute("SELECT object_id, frame_number, x_top_left, y_top_left, x_bottom_right, y_bottom_right FROM bounding_boxes")