光学学报, 2020, 40 (1): 0111001, 网络出版: 2020-01-06
计算光场成像 下载: 7842次特邀综述
Computational Light Field Imaging
成像系统 计算摄像 光场成像 十亿像素 阵列相机 imaging systems computational photography light field imaging gigapixel array camera
摘要
光场为三维世界中光线集合的完备表示。通过记录更高维度的光线数据,光场能够准确感知周围复杂多变的动态环境,支撑智能系统对环境的理解与决策。计算光场成像技术围绕光场及全光函数表示,旨在结合计算、数字传感器、光学系统和智能光照等技术,以及硬件设计、软件计算能力,突破经典成像模型和数字相机的局限性,建立光在空域、视角、光谱和时域等多个维度的关系,实现耦合感知、解耦重建与智能处理,具备面向大范围动态场景的多维多尺度成像能力。光场成像技术正逐渐被应用于生命科学、工业探测、****、无人系统和虚拟现实/增强现实等领域,具有重要的学术研究价值和广阔的产业应用前景。然而,伴随着高维数据的离散化采样,光场成像面临空间分辨率与视角分辨率的维度权衡挑战,如何对稀疏化的采样数据进行光场重建成为计算光场成像及其应用的基础难题。与此同时,受制于光场信号的高维数据感知量,光场处理面临有效数据感知与计算高效性的矛盾。如何用光场这一高维信息采集手段,取代传统二维成像视觉感知方法,并结合智能信息处理技术实现智能化高效感知,是实现光场成像技术产业化应用的巨大挑战。对过去20年来计算光场成像装置与算法的研究进行概述和讨论,内容涵盖光场表示和理论、光场信号采集、空间与视角维度重建等。
Abstract
High performance imaging of large-scale dynamic scenes is substantial to vision intelligence. The light field is a 3D plenoptic function that describes the amount of light flow in every direction through every point in space. By recording the high dimensional light signal, the light field can accurately perceive the complex dynamic environment, supporting the understanding and decision-making of the intelligent system. Computational light field imaging technique, based on the light field and the representation of plenoptic function, aims to combine computation, digital sensors, optical system, and intelligent lighting, thereby combining the hardware design and software computing power. This technique breaks through the limits of classical imaging model and digital camera, establishes the relationship among light in spatial, angular, spectral, and temporal dimensions, realizes coupling perception, decoupling reconstruction, and intelligent processing, and leads to the multi-dimensional and multi-scale imaging ability for large-scale dynamic scenes. Light field imaging technique plays vital role in various fields, including life science, industrial inspection, national security, unmanned system, VR/AR, etc., attracting broad interests from both academia and industry. With the discrete sampling of high dimensional data, light field imaging faces the challenge of dimension trade-off between spatial resolution and angular resolution. How to reconstruct light field for sparse sampled data becomes a fundamental problem in computational light field imaging and its applications. Meanwhile, limited by high dimensional data perception of light field signals, light field process faces the contradiction between effective data perception and computational efficiency. How to replace the traditional two-dimensional imaging visual perception method with light field which is a high-dimensional information acquisition means and how to combine intelligent information processing technique to realize intelligent efficient perception, are huge challenges for industrial applications of the light field imaging technique. In this paper, we conduct a thorough literature review of devices and algorithms of computational light field imaging, including the representation and theory of light field, light field signal sampling, and light field reconstruction with super-resolution in spatial and angular domain.
方璐, 戴琼海. 计算光场成像[J]. 光学学报, 2020, 40(1): 0111001. Lu Fang, Qionghai Dai. Computational Light Field Imaging[J]. Acta Optica Sinica, 2020, 40(1): 0111001.