Difference between recognition, detection, and categorization

For completely understanding this chapter, it is important that you understand that the Viola and Jones detection framework based on cascade classification is actually an object categorization technique and that it differs a lot from the concept of object recognition. This leads to a common mistake in computer vision projects, where people do not analyze the problem well enough beforehand and thus wrongfully decide to use this technique for their problems. Take into consideration the setup described in the following figure, which consists of a computer with a camera attached to it. The computer has an internal description of four objects (plane, cup, car, and snake). Now, we consider the case where three new images are supplied to the camera of the system.

A simple computer vision setup

In the case that image A is presented to the system, the system creates a description of the given input image and tries to match it with the descriptions...