|
New Generation Sensors and Applications: Airborne Sensing
|
Research for verification and calibration
of Multi-spectral aerial photographing system(PKNU 3)
Nam-Chun, Cho
Master 1, Pukyong National University, Dept. of Satellite Information Sciences, KOREA,
Telephone : 051)620-6578,
Email: pkphoto78@hanmail.co.kr
Chul-Uong, Choi
Professor, Pukyong National University, Dept. of Satellite Information Sciences, KOREA,
Email: cuchoi@pknu.ac.kr
Seong-Woo, Jeon
Researcher, Korean Environment Institute, KOREA,
Telephone: 02) 380-7661,
Email: swjeon@kei.re.kr
Hui-Chul, Jung
Researcher, Korean Environment Institute, KOREA,
Telephone: 02) 380-7780,
Email: hchjung@kei.re.kr
Abstract
In this study, we quantify the spectral characteristics of the multi-spectral camera (REDLAKE
MS 4000) and the thermal infrared sensor (Raytheon IRPro) that would be used in the small-format
aerial photographing system named PKNU 3 developed by our laboratory. We compute
the radial lens distortion of the multi-spectral camera by surveying a series of GCPs (Ground
Control Point), and analyzing the accuracy after correcting detected distortion. By analyzing the
correlation between the radiant energy in each band and the brightness value on the image, we
also computed the sensitivity of each band on each CCD that should be corrected for
maintaining the proper balance among R, G, B, and IR bands on an image. We estimated the
sensitivity of thermal infrared sensor by analyzing the correlation between the brightness value
on the image and radiation temperature associated with the Emissivity of each object. In this
study, we allow for the generation of normalized data from PKNU 3 imagery by determining the
spectral characteristics of each sensor. Thus, these equipment calibration techniques can give
equipment such as the PKNU 3 added value in roles such asenvironmental monitoring.
1. Introduction
The multi-spectral sensor (MS 4000) that is implemented in the multi-spectral aerial
photographing system (PKNU 3) uses a triple CCD (R, B&G, and IR) sensor, as opposed to a
camera with a single CCD, so that more precise data on each band channel in any particular
image may be obtained. Quantifying the various characteristics of camera lens distortion, the
individual band sensitivity of each CCD, and the sensitivity of the thermal infrared sensor
allows for the normalization of data to result in a more accurate image. Presently, few studies
have been undertaken to analyze lens distortion and mitigate its effects on digital camera
photography. A domestic program has studied the analysis and techniques to correct the lens
distortion of the CCD camera for mobile mapping system (Dong-hun Jeong, 2002). In a foreign
study, studying the possibility of generating a digital map in a narrow area using Kodak
DCS460 cameras, the issue of lens distortion was discussed (S.Manson et al., 1997; Clive
S.Fraser et al., 1997).
|
|
|
|
|
