An analog VLSI for analog-to-binary image conversion

The conventional process of acquiring a binary image is an inefficient proc ess that obtains a high resolution image from the source image-analog data- by consuming hardware resources such 6- to 8-bit A-D converters and time fo r scanning and A-D conversion at each pixel, followed by conversion to bina ry values by digital processing. In this paper, we propose an analog comput ation circuit for implementing a binarization algorithm that utilizes a thr eshold decision technique based on the lease mean squares criterion. By int egrating this circuit on the same chip as the photosensor to acquire the bi nary image directly from the analog data of the source image, a reduction i n the image read time, which is the bottleneck in high-speed image processi ng, can be expected. (C) 2000 Scripta Technica.