Automatic segmentation and classification of seven-segment display digits on auroral images

In this paper we describe a new and fully automatic method for segmenting and classifying digits in seven-segment displays. The method is applied to a dataset consisting of about 7 million auroral all-sky images taken during the time period of 1973–1997 at camera stations centred around Sodankylä ob...

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Bibliographic Details
Published in:Geoscientific Instrumentation, Methods and Data Systems
Main Authors: Savolainen, Tuomas, Whiter, Daniel Keith, Partamies, Noora
Format: Article in Journal/Newspaper
Language:English
Published: Copernicus Publications 2016
Subjects:
Online Access:https://doi.org/10.5194/gi-5-305-2016
https://noa.gwlb.de/receive/cop_mods_00011813
https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00011770/gi-5-305-2016.pdf
https://gi.copernicus.org/articles/5/305/2016/gi-5-305-2016.pdf
Description
Summary:In this paper we describe a new and fully automatic method for segmenting and classifying digits in seven-segment displays. The method is applied to a dataset consisting of about 7 million auroral all-sky images taken during the time period of 1973–1997 at camera stations centred around Sodankylä observatory in northern Finland. In each image there is a clock display for the date and time together with the reflection of the whole night sky through a spherical mirror. The digitised film images of the night sky contain valuable scientific information but are impractical to use without an automatic method for extracting the date–time from the display. We describe the implementation and the results of such a method in detail in this paper.