AN EFFICIENT CONTRAST-ENHANCEMENT METHOD USING THE ANALOG-TO-DIGITAL CONVERTER

The study presents a hybrid method of contrast enhancement using the a nalog to digital converter (ADC) for use in high-speed industrial appl ications. The proposed framework processes the digitized image in effi cient steps to generate the low and high offsets of the ADC. These off sets are used to modify the analog image signal by an affine transform , such that the digitization of the transformed signal is the enhanced image. Since the signal transformation is mostly done in the analog d omain, the method is efficient, and its implementation is inexpensive. As an example, the enhancement method is used in applications where, given images of varying initial contrast, we can obtain an user-specif ied contrast for all images. These images are then segmented by a simp ler image-processing algorithm. The method is a generalization of exis ting ADC-based enhancement methods and is compared experimentally to t he digital domain techniques. An application of the method is given fo r the enhancement of laser-etched characters on industrial parts.