THEORY

Selecting reference velocities can be thought of as a non-linear problem. Choosing a reference velocity to use at a given location is a function of which reference velocity is actually closest to the given velocity, which makes posing the problem in a traditional linear framework difficult. When compressing signals, electrical engineers face a similar problem. They try to describe a signal with as few bytes as possible. To do this they develop a codebook. Each member of the codebook represents a region described by a single value.