Reflectance Measurement Method Based on Sensor Fusion of Frame-Based Hyperspectral Imager and Time-of-Flight Depth Camera
Abstract
Hyperspectral imaging and distance data have previously been used in aerial, forestry, agricultural, and medical imaging applications. Extracting meaningful information from a combination of different imaging modalities is difficult, as the image sensor fusion requires knowing the optical properties of the sensors, selecting the right optics and finding the sensors’ mutual reference frame through calibration. In this research we demonstrate a method for fusing data from Fabry–Perot interferometer hyperspectral camera and a Kinect V2 time-of-flight depth sensing camera. We created an experimental application to demonstrate utilizing the depth augmented hyperspectral data to measure emission angle dependent reflectance from a multi-view inferred point cloud. We determined the intrinsic and extrinsic camera parameters through calibration, used global and local registration algorithms to combine point clouds from different viewpoints, created a dense point cloud and determined the angle dependent reflectances from it. The method could successfully combine the 3D point cloud data and hyperspectral data from different viewpoints of a reference colorchecker board. The point cloud registrations gained 0.29–0.36 fitness for inlier point correspondences and RMSE was approx. 2, which refers a quite reliable registration result. The RMSE of the measured reflectances between the front view and side views of the targets varied between 0.01 and 0.05 on average and the spectral angle between 1.5 and 3.2 degrees. The results suggest that changing emission angle has very small effect on the surface reflectance intensity and spectrum shapes, which was expected with the used colorchecker.
Main Authors
Format
Articles
Research article
Published
2022
Series
Subjects
Publication in research information system
Publisher
MDPI AG
The permanent address of the publication
https://urn.fi/URN:NBN:fi:jyu-202212135584Use this for linking
Review status
Peer reviewed
ISSN
1424-8220
DOI
https://doi.org/10.3390/s22228668
Language
English
Published in
Sensors
Citation
- Rahkonen, S., Lind, L., Raita-Hakola, A.-M., Kiiskinen, S., & Pölönen, I. (2022). Reflectance Measurement Method Based on Sensor Fusion of Frame-Based Hyperspectral Imager and Time-of-Flight Depth Camera. Sensors, 22(22), Article 8668. https://doi.org/10.3390/s22228668
Funder(s)
Council of Tampere Region
Funding program(s)
ERDF European Regional Development Fund, React-EU
EAKR Euroopan aluekehitysrahasto, React-EU
Additional information about funding
The work is related to the iADDVA—Adding Value by Creative Industry Platform project that has received funding from Council of Tampere Region (Decision number: A77069) and European Regional Development Fund React-EU (2014–2023) and Leverage from the EU 2014–2020. This project has been funded with support from the European Commission.
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