1. A computer program product residing on a computer readable medium for causing a reading machine to operate in different modes that optimize performance for specific uses of the reading machine, the computer program product comprises instructions for causing the reading machine to: receive data that specifies a mode of a plurality of modes that the reading machine is capable of operating in to use for processing images captured by the reading machine; access a knowledge base to provide data to configure the computer program product for the specified mode, with the data including specific target visual elements that are expected to be encountered in processing images captured by the reading machine in the specified mode; capture one or several images; and process the one or several images to identify one or more of the target elements in the one or several images using information including the data including specific target visual elements obtained from the knowledge base.