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README.md

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-license: other
-license_name: cc-by-nc-4.0
-license_link: https://creativecommons.org/licenses/by-nc/4.0/deed.en
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+---
+license: other
+license_name: cc-by-nc-4.0
+license_link: https://creativecommons.org/licenses/by-nc/4.0/deed.en
+---
+
+
+# Image Source and Usage License
+
+The DOTA images are collected from the Google Earth, GF-2 and JL-1 satellite provided by the China Centre for Resources Satellite Data and Application, and aerial images provided by CycloMedia B.V. DOTA consists of RGB images and grayscale images. The RGB images are from Google Earth and CycloMedia, while the grayscale images are from the panchromatic band of GF-2 and JL-1 satellite images. All the images are stored in 'png' formats.
+
+Use of the Google Earth images must respect the "Google Earth" terms of use.
+
+All images and their associated annotations in DOTA can be used for academic purposes only, but any commercial use is prohibited. https://captain-whu.github.io/DOTA/dataset.html