Chapter 5. Detecting Foreground/Background Regions and Depth

This chapter shows how to use data from a depth camera to identify foreground and background regions, such that we can limit an effect to only the foreground or only the background. As prerequisites, we need a depth camera, such as Microsoft Kinect, and we need to build OpenCV with support for our depth camera. For build instructions, see Chapter 1, Setting up OpenCV.

Creating modules

Our code for capturing and manipulating depth-camera data will be reusable outside Cameo.py. So we should separate it into a new module. Let's create a file called depth.py in the same directory as Cameo.py. We need the following import statement in depth.py:

import numpy

We will also need to modify our preexisting rects.py file so that our copy operations can be limited to a non-rectangular sub region of a rectangle. To support the changes we are going to make, let's add the following import statements to rects.py:

import numpy
import utils

Finally, the new version of our application will use depth-related functionality. So, let's add the following import statement to Cameo.py:

import depth

Now, let's get deeper into the subject of depth.