A real-time stereo vision sensor based on FPGA realization of orientation code matching

This paper describes a real-time stereo vision sensor based on the Field Programmable Gate Array (FPGA). It was developed using an image matching algorithm called Orientation Code Matching (OCM). Our implementation, using OCM, provides not only high performance, but also flexibility and a greater robustness, all of which are necessary to embed vision sensors in mobile robots and vehicles. The prototype sensor we implemented runs stereo matching with images of 752 by 480 pixels via image sensing chips, at a frame rate of 60 fps. The maximum disparity, using the current design, is 127 pixels at an operating frequency of 53MHz on the FPGA. By changing the parameters of the hardware description, the architecture of our design on the FPGA becomes flexible and expandable to the required size of input images and pixel disparity.

I. Introduction

Use of stereo vision is becoming a practical method for detecting distance between objects. However, many calculations are required in stereo vision processing, causing considerable problems that hinder application to actual systems. Any such systems would need high-speed processors and improved compatibility to ensure higher performance of the stereo matching process. They would require a lot of power and space just for the sensing capability.