Boson-nighttime

In order to collect thermal aerial data, we used FLIR's Boson thermal imager (8.7 mm focal length, 640p resolution, and $50^\circ$ horizontal field of view)\footnote{\url{https://www.flir.es/products/boson/}}. The collected images are nadir at approx. 1m/px spatial resolution. We performed six flights from 9:00 PM to 4:00 AM and label this dataset as \textbf{Boson-nighttime}, accordingly. To create a single map, we first run a structure-from-motion (SfM) algorithm to reconstruct the thermal map from multiple views. Subsequently, orthorectification is performed by aligning the photometric satellite maps with thermal maps at the same spatial resolution. The ground area covered by Boson-nighttime measures $33~\text{km}{^2}$ in total. The most prevalent map feature is the desert, with small portions of farms, roads, and buildings.

The Bing satellite map\footnote{\url{https://www.bing.com/maps/aerial}} is cropped in the corresponding area as our satellite reference map. We tile the thermal map into $512\times512$~px thermal image crops with a stride of $35$ px. Each thermal image crop pairs with the corresponding satellite image crop. Areas covered by three flights of Boson-nighttime are used for training and validation. The remaining areas, covered by the other three flights are used for testing. The train/validation/test splits for Boson-nighttime are $10256$/$13011$/$26568$ pairs of satellite and thermal image crops, respectively.