Kinect

Introduction

A pixel is the smallest unit of an image.

In a black and white image, the pixel will be some shade of gray between 100% black and 100% white. In a color image, pixels are described in terms of RGB values. In all images, a pixel is described by a number that represents its intensity. The larger the number the more memory the pixel needs. A colored image needs more memory than a grayscale image.

The image captured by the Kinect is 640 pixels by 480 pixels (or 307,200 pixels). Each pixel's number represents both its grayscale intensity and its distance in space. You can use these numbers to either interpret the data as an image or to calculate the distance of the object that the pixel is a part of.

In the captured frame, each pixel can describe the distance between the object and the Kinect. The brightest part of the image (closest to 255) is closest to the Kinect, while the darkest part of the image (closer to 0),is the farther away from the camera.



Lesson

Read Chapter 2 of Greg Borenstein's Making Things See
Setting up SimpleOpenNI
Simple SimpleOpenNI
Images and Arrays
Getting Interactive