Paper Meteotest-Article CSEM-Article

SkyCam dataset is a collection of sky images from a variety of locations with diverse topological characteristics (Swiss Jura, Plateau and Pre-Alps regions), from both single and stereo camera settings coupled with a high-accuracy pyranometers. The dataset was collected with a high frequency with a data sample every 10 seconds. 13 images with different exposures times are generated along with a post-processed HDR images and a solar radiance values for each of the cameras and locations. We hope that SkyCam dataset will enable researchers to tackle the problem of short-term local camera-based solar radiance prediction.

Switzerland is a perfect testing ground for creating a dataset that aims to tackle the problem of short-term solar radiation prediction due to its diverse topological features and volatile meteorological conditions\cite{brunner}. To this extend image and solar radiance capturing equipment was set to three topologically distinct locations, acquiring observations over the span of a year.

In all three locations a single industrial camera was used. In all sites a high-accuracy pyranometer was deployed in order to acquire the irradiance values with high precision. All cameras are industrial-grade CMOS cameras with an appropriate protective casing. The pyranometer is a Hukseflux SR30 designed for for Photovoltaic system performance monitorin and meteorological networks. The solar radiation is received by a plane surface and measured in W/m^2, from a 180° field of view angle

The SkyCam dataset is a collection of images from 365 days from three different locations. Each day has on average 12 hours between dawn and dusk and images are captures with a frequency of 10 seconds. That means that we have approximately 1576800 timestamps per camera. The total size of the dataset is approximately 16 TeraBytes. For each time stamp each camera acquires a series of 13 photographs with different exposure times. After the collection the images are post-processed in order to generate a High-Dynamic-Range (HDR) image. At the same time the solar radiance value is measured by the pyranometer. In Figure 3 we can observe how a particular timestamp looks like. The original resolution of each captured image is 1200x1200 pixels while the generated HDR image has a resolution of 600x600 pixels.

To request access to the dataset please send a enquiry to "info [at] csem [dot] ch" and/or "office [at] meteotest [dot] ch".

Option 1: Upon request will give you the credentials to access the Meteotest ftp server

Option 2: Due to the size of the dataset, copying the files to a physical drive will be a faster solution.

If you find the SkyCam dataset useful to your research/work please cite:

@misc{ntavelis2021skycam,
      title={SkyCam: A Dataset of Sky Images and their Irradiance values}, 
      author={Evangelos Ntavelis and Jan Remund and Philipp Schmid},
      year={2021},
      eprint={2105.02922},
      archivePrefix={arXiv},
      primaryClass={cs.CV}
}

Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0)

The development of the SkyCam dataset was funded by the Swiss Federal Office of Energy under grant SI/50151 as a collaborative project between CSEM and Meteotest.