Creating a motion detection animation

So far in this chapter, we learned the basic tools to detect presence and motion. Detecting presence is like a binary switch that indicates the presence or absence of a subject in front of a predefined background. Detecting motion indicates the position of the center of the moving blob object. We have tried using a graphical shape and a piece of text to follow the movement. In the following patch Motion004.pd, we use an image with the pix_image object:

There is no new technique here. Use the pix_image object with an open Flower001.jpg message to open the image file in the same folder with the patch. You also need the pix_texture object to map the image onto the square. In this case, the image will follow your movement:

The image is itself a square. It has a white background color. In some applications, you may want to have an irregular shape with a transparent background. We have learned the use of the pix_mask object to handle it in Chapter 3, Image Processing...