An FPGA-based RGBD imager

Abstract

This paper describes a trinocular stereo vision system using a single chip of FPGA to generate the composite color (RGB) and disparity data stream at video rate, called the RGBD imager. The system uses the triangular configuration of three cameras for synchronous image capture and the trinocular adaptive cooperative algorithm based on local aggregation for smooth and accurate dense disparity mapping. We design a fine-grain parallel and pipelining architecture in FPGA for implementation to achieve a high computational and real-time throughput. A binary floating-point format is customized for data representation to satisfy the wide data range and high computation precision demands in the disparity calculation. Memory management and data bit-width control are applied in the system to reduce the hardware resource consumption and accelerate the processing speed. The system is able to produce dense disparity maps with 320 × 240 pixels in a disparity search range of 64 pixels at the rate of 30 frames per second.