| Autor: |
Hanrui Cao, Xi Li, Zhe Tong |
| Jazyk: |
angličtina |
| Rok vydání: |
2021 |
| Předmět: |
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| Zdroj: |
IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, Vol 14, Pp 7948-7960 (2021) |
| Druh dokumentu: |
article |
| ISSN: |
2151-1535 |
| DOI: |
10.1109/JSTARS.2021.3101837 |
| Popis: |
This article aims to evaluate impact of image saturation on radiometric intercalibration of Defense Meteorological Satellite Program's Operational Linescan System (DMSP/OLS) stable nighttime light (NTL) images. We simulated two sets of stable NTL images, one with saturation and the other without saturation, by using DMSP/OLS radiance calibrated images without saturation. For each dataset, we intercalibrated the simulated images of seven years using a quadratic regression model. We found that the saturation-derived difference of the radiometric intercalibration is more obvious in areas where the digital number value is higher than a certain value (e.g., ∼30). By comparing the calibrated images of the two datasets, we found that the absolute value of the saturation-derived relative bias of the intercalibration tends to be positively correlated to the ratio of saturated pixels in the calibration field, with Pearson correlation of 0.4610 ($p$ < 0.01). Besides, the absolute value of the saturation-derived relative bias is positively correlated to the nonlinearity of the data relationship in the calibration field (measured by the difference between the ${{\boldsymbol{R}}^2}$ of quadratic regression and linear regression), with Pearson correlation of 0.6398 ($p$< 0.01). These findings indicate that the image saturation impacts the intercalibration of the DMSP/OLS stable NTL images, and the impact is affected by the image characteristics. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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