FPGA system for real-time computational extended depth of field imaging using phase aperture coding

TL;DR

This paper introduces an FPGA-based system for real-time extended depth of field imaging using phase aperture coding, combining optical design and fast reconstruction algorithms for improved focus range.

Contribution

It presents a novel end-to-end system integrating phase-coded aperture optics with a real-time FPGA reconstruction algorithm for extended depth of field imaging.

Findings

Achieves real-time, non-iterative reconstruction with constant latency.

Produces qualitatively and quantitatively better images than traditional deblurring methods.

Demonstrates effectiveness on both simulated and real scenes.

Abstract

We present a proof-of-concept end-to-end system for computational extended depth of field (EDOF) imaging. The acquisition is performed through a phase-coded aperture implemented by placing a thin wavelength-dependent optical mask inside the pupil of a conventional camera lens, as a result of which, each color channel is focused at a different depth. The reconstruction process receives the raw Bayer image as the input, and performs blind estimation of the output color image in focus at an extended range of depths using a patch-wise sparse prior. We present a fast non-iterative reconstruction algorithm operating with constant latency in fixed-point arithmetics and achieving real-time performance in a prototype FPGA implementation. The output of the system, on simulated and real-life scenes, is qualitatively and quantitatively better than the result of clear-aperture imaging followed by state-of-the-art blind deblurring.