Development and application of Computer Vision-based algorithm for digitizing archival monitoring observations of powerful cosmic radio source fluxes on the RT URAN-4 (IRA NASU)

1Zabora, DA, 2Ryabov, MI, Sukharev, AI, 3Strakhov, Ye.M, 4Shymbarova, OO
1Institute of Radio Astronomy of the National Academy of Sciences of Ukraine, Kharkiv, Ukraine; Odesa I. I. Mechnikov National University, Odesa, 65082 Ukraine
2Institute of Radio Astronomy of the National Academy of Sciences of Ukraine, Kharkiv, Ukraine
3Odesa I. I. Mechnikov National University, Odesa, 65082 Ukraine
4Odesa I. I. Mechnikov National University, Odesa, 65082 Ukraine
Space Sci. & Technol. 2025, 31 ;(6):123-133
https://doi.org/10.15407/knit2025.06.123
Язык публикации: English
Аннотация: 
This study presents the development and preliminary application of a computer vision-based algorithm for digitizing archival paperbased
records (1987—1992) from the URAN-4 radio telescope. The input data consists of JPEG scans at 300 dpi, with the quality of
the digitized results primarily depending on the quality of the original paper medium. The developed algorithm encompasses several
key stages: identification of the recorder’s curve and grid lines of medium by color; filtering and clustering of grid lines; determination
and correction of scan tilt introduced by imperfect paper medium placement in the scanner; stitching together multiple scans of a single
extended record by detecting and matching time markers on adjacent scans; establishing vertical (intensity) and horizontal (time)
scales; filtering and removing noise components from the signal for subsequent digital processing.
             The research also demonstrates the feasibility and quality of subsequent time-frequency analysis of the obtained signal. This approach
to digitization enables the application of modern digital processing methods to historical monitoring records, allowing for acurcomprehensive
analysis of the frequency characteristics of radio flux variability in time intervals of approximately 1 second and, inparticular, for detailed investigations of ionospheric scintillations. The proposed stitching algorithm facilitates the construction of long-term time series and the digital identification of significant events, offering a new perspective on space weather conditions during historical ionospheric and magnetic storms, the effects of solar and lunar eclipses, and ionospheric tidal lensing. The initial application of this algorithm will focus on analyzing the impact of ionospheric and magnetic storms within the Odesa Magnetic Anomaly zone during the 22nd solar activity cycle.
Ключевые слова: archival radio telescope data digitization, automated chart recognition, computer vision, ionospheric scintillation, machine learning, radio astronomy, time-frequency analysis
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