markers_from_openni_tracker.py
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00001 #!/usr/bin/env python
00002 
00003 """
00004     Convert a skeleton transform tree to a list of visualization markers for RViz.
00005         
00006     Created for the Pi Robot Project: http://www.pirobot.org
00007     Copyright (c) 2011 Patrick Goebel.  All rights reserved.
00008 
00009     This program is free software; you can redistribute it and/or modify
00010     it under the terms of the GNU General Public License as published by
00011     the Free Software Foundation; either version 2 of the License, or
00012     (at your option) any later version.
00013     
00014     This program is distributed in the hope that it will be useful,
00015     but WITHOUT ANY WARRANTY; without even the implied warranty of
00016     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00017     GNU General Public License for more details at:
00018     
00019     http://www.gnu.org/licenses/gpl.html
00020 """
00021 
00022 import rospy
00023 from visualization_msgs.msg import Marker
00024 from geometry_msgs.msg import Point
00025 import tf
00026 import re
00027 
00028 class SkeletonMarkers():
00029     def __init__(self):
00030         rospy.init_node('markers_from_tf')
00031                 
00032         rospy.loginfo("Initializing Skeleton Markers Node...")
00033         
00034         rate = rospy.get_param('~rate', 20)
00035         r = rospy.Rate(rate)
00036         tf_prefix = rospy.get_param('~tf_prefix', '')
00037         skeleton_frames = rospy.get_param('~skeleton_frames', '')
00038         self.fixed_frame = rospy.get_param('~fixed_frame', 'openni_depth_frame')
00039         
00040         # Normalize the tf_prefix variable with / at the beginning and end
00041         tf_prefix = '/' + tf_prefix + '/'
00042         tf_prefix = re.sub('/+', '/', tf_prefix)
00043         
00044         # Normalize the tf_prefix variable with / at the beginning and end
00045         self.fixed_frame = '/' + tf_prefix + '/' + self.fixed_frame
00046         self.fixed_frame = re.sub('/+', '/', self.fixed_frame)
00047 
00048         # Initialize tf listener
00049         tf_listener = tf.TransformListener()
00050         
00051         # Define a marker publisher
00052         marker_pub = rospy.Publisher('skeleton_markers', Marker)
00053         
00054         # Intialize the markers
00055         self.init_markers()
00056         
00057         # The openni_tracker identifies each skeleton frame with a user_id beginning
00058         # with 1 and incrementing as new users are tracked.
00059         user_id = None
00060         
00061         # Get the list of all skeleton frames from tf
00062         #skeleton_frames = [f for f in tf_listener.getFrameStrings() if f.startswith("/" + self.tf_prefix)]
00063         
00064                
00065         # Begin the main loop
00066         while not rospy.is_shutdown():
00067             # Get a list of all frames
00068             all_frames = [f for f in tf_listener.getFrameStrings()]
00069             
00070             # Test for the user ID to track
00071             try:
00072                 test = all_frames.index(tf_prefix + 'torso')
00073                 user_id = ""
00074             except:
00075                 try:
00076                     test = all_frames.index(tf_prefix + 'torso_1')
00077                     user_id = "_1"
00078                 except:
00079                     pass
00080             
00081             if user_id is None:
00082                 r.sleep
00083                 continue
00084             
00085             # Get all skeleton frames for the detected user user
00086             user_frames = list()
00087     
00088             for frame in skeleton_frames:
00089                 qualified_frame = tf_prefix + frame + user_id
00090                 try:
00091                     all_frames.index(qualified_frame)
00092                     user_frames.append(qualified_frame)
00093                 except:
00094                     pass
00095                 
00096             #tf_listener.waitForTransform(self.fixed_frame, user_frames[0], rospy.Time(), rospy.Duration(25.0))
00097 
00098             # Set the markers header
00099             self.markers.header.stamp = rospy.Time.now()
00100             
00101             # Clear the markers point list
00102             self.markers.points = list()
00103             
00104             # Loop through the skeleton frames
00105             for frame in user_frames:
00106                 if frame == self.fixed_frame:
00107                     continue
00108                 # Find the position of the frame's origin relative to the fixed frame.
00109                 try:
00110                     position = Point()
00111                     
00112                     # Get the transformation from the fixed frame to the skeleton frame
00113                     (trans, rot)  = tf_listener.lookupTransform(self.fixed_frame, frame, rospy.Time(0))
00114                     position.x = trans[0]
00115                     position.y = trans[1]
00116                     position.z = trans[2]
00117                                         
00118                     # Set a marker at the origin of this frame
00119                     self.markers.points.append(position)
00120                 except (tf.Exception, tf.ConnectivityException, tf.LookupException):
00121                     rospy.logerr("tf error when looking up " + frame + ' and ' + self.fixed_frame)
00122                     continue
00123             
00124             # Publish the set of markers
00125             marker_pub.publish(self.markers)                       
00126             r.sleep()
00127             
00128     def init_markers(self):
00129         # Set various parameters
00130         scale = rospy.get_param('~scale', 0.07)
00131         lifetime = rospy.get_param('~lifetime', 0) # 0 is forever
00132         ns = rospy.get_param('~ns', 'skeleton_markers')
00133         id = rospy.get_param('~id', 0)
00134         color = rospy.get_param('~color', {'r': 0.0, 'g': 1.0, 'b': 0.0, 'a': 1.0})
00135         
00136         # Initialize the marker points list
00137         self.markers = Marker()
00138         self.markers.header.frame_id = self.fixed_frame
00139         self.markers.ns = ns
00140         self.markers.id = id
00141         self.markers.type = Marker.POINTS
00142         self.markers.action = Marker.ADD
00143         self.markers.lifetime = rospy.Duration(lifetime)
00144         self.markers.scale.x = scale
00145         self.markers.scale.y = scale
00146         self.markers.color.r = color['r']
00147         self.markers.color.g = color['g']
00148         self.markers.color.b = color['b']
00149         self.markers.color.a = color['a']
00150         
00151 if __name__ == '__main__':
00152     try:
00153         SkeletonMarkers()
00154     except rospy.ROSInterruptException:
00155         pass


skeleton_markers
Author(s): Patrick Goebel
autogenerated on Fri Aug 28 2015 13:09:12