In a
machine vision
system utilizing
computer processing of image data, an imaging module incorporates the
image sensor as well as pre-
processing circuitry, for example, for performing a
background subtraction and / or a gradient calculation. The pre-
processing circuitry may also compress the image information. The host computer receives the pre-processed image data and performs all other calculations necessary to complete the
machine vision application, for example, to determine one or more
wheel alignment parameters of a subject vehicle. In a disclosed example useful for
wheel alignment, the module also includes illumination elements, and the module circuitry provides associated
camera control. The
background subtraction, gradient calculation and associated compression require simpler, less expensive circuitry than for typical image pre-
processing boards. Yet, the pre-processing at the imaging module substantially reduces the processing burden on the host computer when compared to
machine vision implementations using direct streaming of image data to the host computer.