Title: Volumetric calibration of a plenoptic camera

Abstract

Here, the volumetric calibration of a plenoptic camera is explored to correct for inaccuracies due to real-world lens distortions and thin-lens assumptions in current processing methods. Two methods of volumetric calibration based on a polynomial mapping function that does not require knowledge of specific lens parameters are presented and compared to a calibration based on thin-lens assumptions. The first method, volumetric dewarping, is executed by creation of a volumetric representation of a scene using the thin-lens assumptions, which is then corrected in post-processing using a polynomial mapping function. The second method, direct light-field calibration, uses the polynomial mapping in creation of the initial volumetric representation to relate locations in object space directly to image sensor locations. The accuracy and feasibility of these methods is examined experimentally by capturing images of a known dot card at a variety of depths. Results suggest that use of a 3D polynomial mapping function provides a significant increase in reconstruction accuracy and that the achievable accuracy is similar using either polynomial-mapping-based method. Additionally, direct light-field calibration provides significant computational benefits by eliminating some intermediate processing steps found in other methods. Finally, the flexibility of this method is shown for a nonplanar calibration.

Authors:

Hall, Elise Munz ^[1]; Fahringer, Timothy W. ^[2]; Guildenbecher, Daniel Robert ^[3]; Thurow, Brian S. ^[2]

---

+ Show Author Affiliations

1. Auburn Univ., Auburn, AL (United States); Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
2. Auburn Univ., Auburn, AL (United States)
3. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

Publication Date:

Thu Feb 01 00:00:00 EST 2018

Research Org.:

Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

Sponsoring Org.:

USDOE National Nuclear Security Administration (NNSA)

OSTI Identifier:

1421765

Alternate Identifier(s):

OSTI ID: 1418726

Report Number(s):

SAND-2018-0806J
Journal ID: ISSN 1559-128X; APOPAI; 660487

Grant/Contract Number:  

AC04-94AL85000; NA0003525

Resource Type:

Accepted Manuscript

Journal Name:

Applied Optics

Additional Journal Information:

Journal Volume: 57; Journal Issue: 4; Journal ID: ISSN 1559-128X

Publisher:

Optical Society of America

Country of Publication:

United States

Language:

English

Subject:

47 OTHER INSTRUMENTATION; three-dimensional image processing; three-dimensional image acquisition