Analog VLSI Circuits for the Perception of Visual Motion

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Visual Motion Perception

Visual motion perception is the process an observer performs in order to extract relative motion between itself and its environment using visual information only. Typically, the observer possesses one or more imaging devices, such as eyes or cameras. These devices sense images that are the two-dimensional projection of the intensity distribution radiating from the surfaces of the environment. When the observer moves relative to its environment, its motion is reflected in the images accordingly. Because of this causal relationship, being able to perceive image motion provides the observer with useful information about the relative physical motion. The problem is that the physical motion is only implicitly represented in the spatio-temporal brightness changes reported by the imaging devices. It is the task of visual motion perception to interpret the spatio-temporal brightness pattern and extract image motion in a meaningful way.

This chapter will outline the computational problems involved in the perception of visual motion, and provide a rough concept of how a system for visual motion perception should be constructed. The concept follows an ecological approach. Visual motion perception is considered to be performed by a completely autonomous observer behaving in a real-world environment. Consequently, I will discuss the perceptual process with respect to the needs and requirements of the observer. Every now and then, I will refer also to biological visual ...