CHAPTER 16 The Three-Dimensional World
In the forgoing chapters, it has been assumed that objects are essentially flat and are viewed from above in such a way that there are only three degrees of freedom—namely, the two associated with position and one concerned with orientation. Although this approach was adequate for carrying out many useful visual tasks, it is totally inadequate for interpreting outdoor or factory scenes, or even for helping with quite simple robot assembly and inspection tasks. Over the past 25 years or so a considerable amount of sophisticated theory has been developed and backed up by experiment, to find how scenes composed of real 3-D objects can be understood in detail.
In general, this means attempting ...