A Relative Radiometric Calibration Method Based on the Histogram of Side-Slither Data for High-Resolution Optical Satellite Imagery

Mi Wang,Jun Pan,Xueli Chang,Ying Zhu,Chaochao Chen

doi:10.3390/rs10030381

Abstract

Relative radiometric calibration, or flat fielding, is indispensable for obtaining high-quality optical satellite imagery for sensors that have more than one detector per band. High-resolution optical push-broom sensors with thousands of detectors per band are now common. Multiple techniques have been employed for relative radiometric calibration. One technique, often called side-slither, where the sensor axis is rotated 90° in yaw relative to normal acquisitions, has been gaining popularity, being applied to Landsat 8, QuickBird, RapidEye, and other satellites. Side-slither can be more time efficient than some of the traditional methods, as only one acquisition may be required. In addition, the side-slither does not require any onboard calibration hardware, only a satellite capability to yaw and maintain a stable yawed attitude. A relative radiometric calibration method based on histograms of side-slither data is developed. This method has three steps: pre-processing, extraction of key points, and calculation of coefficients. Histogram matching and Otsu’s method are used to extract key points. Three datasets from the Chinese GaoFen-9 satellite were used: one to obtain the relative radiometric coefficients, and the others to verify the coefficients. Root-mean-square deviations of the corrected imagery were better than 0.1%. The maximum streaking metrics was less than 1. This method produced significantly better relative radiometric calibration than the traditional method used for GaoFen-9.

Highlights

With the development of remote sensing technology, a new generation of high-resolution optical remote sensing satellites has been broadly applied to scientific experiments, land surveying, crop yield assessment, and environmental monitoring
It was difficult to verify the quality of the remote sensing images using uniform field data, because even the most uniform deserts have features that diverge from absolutely uniform field data
Based on the characteristics of the side-slither data and the standard image obtained from data pre-processing, we used the most uniform feature in the linear direction

Summary

Introduction

With the development of remote sensing technology, a new generation of high-resolution optical remote sensing satellites has been broadly applied to scientific experiments, land surveying, crop yield assessment, and environmental monitoring. Each detector in push-broom imaging mode should have exactly the same output when the incident radiance into the entrance pupil of the camera is uniform. This ideal state is not realized, due to several factors, and the response of each detector is not identical. To improve the visual quality of the image and the identification of the target, the image must be corrected This process is called relative radiometric correction, and is a key step in producing high-quality images. Relative radiometric calibration is an indispensable processing procedure for improving the quality of high-resolution optical satellite imagery [2,3]

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Discussion

Conclusion