Object detection refers to detecting the location of an object in a given image. This process is not concerned with the type of object. If you design a chair detector, it will not tell you whether the chair in a given image is red with a high back, or blue with a low back—it will just tell you the location of the chair.
Detecting the location of objects is a critical step in many computer vision systems. Consider the following photo:
If you run a chair detector on this image, it will put a green box around all the chairs—but it won't tell you what kind of chair it is.
Object detection used to be a computationally-intensive ...