A Case Study On Approximate FPGA Design With an Open-Source Image Processing Platform

This paper presents a case study of approximate design with Field-Programmable Gate Array (FPGA), combining an application of a color to grayscale converter and an open image/video processing platform with Verilog hardware description language (HDL). First of all, by integrating two approximations of adders and two approximations of multipliers, together with the exact design, nine different approximations of the design on color to grayscale converter are offered. Second, the image processing platform is presented to demonstrate the proposed work on Nexys-4 FPGA, enabling to capture color images through a low-cost OV7670 camera and display the grayscale results of images on a VGA-interfaced monitor. Experimental results show the difference between different approximations of the design, providing a range of design options corresponding to different quality constrains.