12. 11. 2018

Sky sensor aggregator

We have developed software for interval shooting of the daytime sky (image collection, pre-processing and sending to a computer server). The software is intended for additional equipment to the IP camera.

It can be downloaded at GitHub for UCEEB: UCEEB / Sky-Imager-Aggregator

Standalone software is implemented in Python. The software is designed for Raspberry Pi devices. The intended use presupposes a functional connection with an IP camera and a connection to the Internet. The software can handle short-term Internet outages, depending on the size of the external memory of the Raspberry Pi on which it is installed, ensuring continuous scanning.

Purpose and features

The system for forecasting exposure based on sky imaging uses the so-called Sky Imager, which is a device typically composed of a panoramic IP camera and a Raspberry Pi device. Sky Imager Aggregator is a utility software running on the Raspberry Pi.

The goal of the developed software is to acquire images of the sky at predefined intervals and time spans. These images are pre-processed mainly by applying a predefined mask, which filters out unwanted (typically static) objects from the image.

The images are then sent to a computer server for further processing via a secure interface. If the image cannot be sent, it is stored in the device’s external memory for later transmission. The software in combination with the device thus significantly increases the resistance of scanning against internet connection failures. This ensures long-term continuous sensing, which is important for the development and testing of prediction algorithms.


The software is intended for installation on Raspberry Pi devices. It is assumed that the Raspberry will be connected to the Internet and that it will also be connected to the IP camera. The settings of the network interface towards the IP camera are determined by the settings of the camera itself (fixed IP address, subnet mask), which must correspond to the settings of the used interface on the Raspberry Pi. Powering the camera may require a POE injector.

The setting of common parameters is given by the configuration file config, ini , which is located in the directory config . For more details, see the project documentation on the web: -Aggregator / tree / master / doc .