Source Code for Module pyvision.types.kinect

 1  ''' 
 2  Created on Jan 28, 2012 
 3   
 4  @author: bolme 
 5  ''' 
 6  #import freenect 
 7  import cv 
 8  import numpy as np 
 9  import pyvision as pv 
10   
11   
12  # Here is a nice pythonic interface to the kinect sensor for pyvision 
13 -class Kinect(object): 
14      ''' 
15      This class provides a simple interface to the kinect sensor.  When operating  
16      properly the device produces an color RGB video frame (8bit 640x480) and a  
17      depth image (11-bit, 640x480) at around 20-24 frames per second with low latency. 
18   
19       
20      The kinect drivers to not appear to be robust.  Some trial and error may be 
21      needed to determine how to best interface with the device. Here are some problem  
22      behaviours that I have seen: # 
23        * The Kinect does not seem to start properly. 
24        * Calling some functions in the freenect module results in segmentation 
25          faults 
26        * Connecting to the sensor temporarily or perminatly interupts the usb 
27          bus. (The keyboard and mouse stop working.) 
28        * The device seems to work better when connected to one of the ports on 
29          my laptop but not the other. 
30        * The device sometimes prints out error/warning messages which do not seem 
31          to interfere with the operation of the device. 
32          "[Stream 70] Expected 1748 data bytes, but got 948" # 
33           
34      After connecting the device to the usb port it may be helpful to initialize  
35      the device using ipython.  Try running these commands before connecting through 
36      pyvision or attempting to grab frames:  
37       
38      import freenect 
39      freenect.init() # start the connection 
40      exit 
41       
42      The current implementation initializes the device and returns RGB and depth 
43      frames.  No advanced features such as LED, Audio, or Tilt are supported because 
44      they cause sementation violations. 
45       
46      ''' 
47       
48 -    def __init__(self): 
49          ''' 
50          Initialize a Kinect device. 
51          ''' 
52          # Try importing the freenect library.   
53          import freenect as fn #@UnresolvedImport 
54          self.fn = fn 
55          self.fn.init() 
56           
57 -    def __iter__(self): 
58          ''' Return an iterator for this video ''' 
59          return self 
60   
61 -    def next(self): 
62          ''' 
63          Get the next frame and depth image from the sensor. 
64          ''' 
65          # This is an 11bit numpy array 
66          depth = self.fn.sync_get_depth()[0] 
67           
68          # This is an 8 bit numpy array 
69          frame = self.fn.sync_get_video()[0] 
70           
71          r,c,chan = frame.shape 
72           
73          cvframe = cv.CreateImageHeader((c,r),cv.IPL_DEPTH_8U,chan) 
74          cv.SetData(cvframe,frame.tostring(),3*c) 
75          cv.CvtColor(cvframe,cvframe,cv.CV_RGB2BGR) 
76          return pv.Image(cvframe),pv.Image(np.array(depth.T,dtype=np.float)) 
77       
78  # The main function that runs some tests     
79  if __name__ == '__main__': 
80      print "Testing the kinect sensor." 
81      print "Press any key to quit" 
82       
83      kinect = pv.Kinect() 
84      for frame, depth in kinect: 
85          # Display the images 
86          k = max( 
87                  depth.show(window="Depth",delay=1,pos=(100,100)), 
88                  frame.show(window="Video",delay=1,pos=(740,100)) 
89                  ) 
90           
91          # Check to see if a key was pressed 
92          if k != -1: 
93              break 
94