Setting up the app

Before we can get down to the nitty-gritty of our gesture recognition algorithm, we need to make sure that we can access the Kinect sensor and display a stream of depth frames in a simple GUI.

Accessing the Kinect 3D sensor

Accessing Microsoft Kinect from within OpenCV is not much different from accessing a computer's webcam or camera device. The easiest way to integrate a Kinect sensor with OpenCV is by using an OpenKinect module called freenect. For installation instructions, take a look at the preceding information box. The following code snippet grants access to the sensor using cv2.VideoCapture:

import cv2
import freenect


device = cv2.cv.CV_CAP_OPENNI
capture = cv2.VideoCapture(device)

On some platforms, the first call to cv2.VideoCapture fails to open a capture channel. In this case, we provide a workaround by opening the channel ourselves:

if not(capture.isOpened(device)):
    capture.open(device)

If you want to connect to your Asus Xtion, the device variable...