A Novel Line-Scan Algorithm for Unsynchronised Dynamic Measurements
In non-destructive inspections today, the size of the sample being examined is often limited to fit within the field of view of the camera being used. When examining larger specimens, multiple image sequences need to be stitched together into one image. Due to uneven illumination, the combined image...
| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | English |
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MDPI AG
2023-12-01
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| Series: | Applied Sciences |
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| Online Access: | https://www.mdpi.com/2076-3417/14/1/235 |
| _version_ | 1797359173531336704 |
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| author | Simon Verspeek Thomas De Kerf Bart Ribbens Xavier Maldague Steve Vanlanduit Gunther Steenackers |
| author_facet | Simon Verspeek Thomas De Kerf Bart Ribbens Xavier Maldague Steve Vanlanduit Gunther Steenackers |
| author_sort | Simon Verspeek |
| collection | DOAJ |
| description | In non-destructive inspections today, the size of the sample being examined is often limited to fit within the field of view of the camera being used. When examining larger specimens, multiple image sequences need to be stitched together into one image. Due to uneven illumination, the combined image may have artificial defects. This manuscript provides a solution for performing line-scan measurements from a sample and combining the images to avoid these artificial defects. The proposed algorithm calculates the pixel shift, either through checkerboard detection or by field of view (FOV) calculation, for each image to create the stitched image. This working principle eliminates the need for synchronisation between the motion speed of the object and the frame rate of the camera. The algorithm is tested with several cameras that operate in different wavelengths (ultraviolet (UV), visible near infrared (Vis-NIR) and long-wave infrared (LWIR)), each with the corresponding light sources. Results show that the algorithm is able to achieve subpixel stitching accuracy. The side effects of heterogeneous illumination can be solved using the proposed method. |
| first_indexed | 2024-03-08T15:11:56Z |
| format | Article |
| id | doaj.art-e2ff534a139a433abd8669390d7d2580 |
| institution | Directory Open Access Journal |
| issn | 2076-3417 |
| language | English |
| last_indexed | 2024-03-08T15:11:56Z |
| publishDate | 2023-12-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Applied Sciences |
| spelling | doaj.art-e2ff534a139a433abd8669390d7d25802024-01-10T14:51:26ZengMDPI AGApplied Sciences2076-34172023-12-0114123510.3390/app14010235A Novel Line-Scan Algorithm for Unsynchronised Dynamic MeasurementsSimon Verspeek0Thomas De Kerf1Bart Ribbens2Xavier Maldague3Steve Vanlanduit4Gunther Steenackers5Faculty of Applied Engineering, Department Electromechanics, Research Group InViLab, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, BelgiumFaculty of Applied Engineering, Department Electromechanics, Research Group InViLab, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, BelgiumFaculty of Applied Engineering, Department Electromechanics, Research Group InViLab, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, BelgiumComputer Vision and Systems Laboratory, Department of Electrical and Computer Engineering, Université Laval, Quebec City, QC G1V 0A6, CanadaFaculty of Applied Engineering, Department Electromechanics, Research Group InViLab, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, BelgiumFaculty of Applied Engineering, Department Electromechanics, Research Group InViLab, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, BelgiumIn non-destructive inspections today, the size of the sample being examined is often limited to fit within the field of view of the camera being used. When examining larger specimens, multiple image sequences need to be stitched together into one image. Due to uneven illumination, the combined image may have artificial defects. This manuscript provides a solution for performing line-scan measurements from a sample and combining the images to avoid these artificial defects. The proposed algorithm calculates the pixel shift, either through checkerboard detection or by field of view (FOV) calculation, for each image to create the stitched image. This working principle eliminates the need for synchronisation between the motion speed of the object and the frame rate of the camera. The algorithm is tested with several cameras that operate in different wavelengths (ultraviolet (UV), visible near infrared (Vis-NIR) and long-wave infrared (LWIR)), each with the corresponding light sources. Results show that the algorithm is able to achieve subpixel stitching accuracy. The side effects of heterogeneous illumination can be solved using the proposed method.https://www.mdpi.com/2076-3417/14/1/235non-destructive inspectionsdynamic line-scan thermographyultraviolet measurementsdynamic measurementsmultispectral imaging |
| spellingShingle | Simon Verspeek Thomas De Kerf Bart Ribbens Xavier Maldague Steve Vanlanduit Gunther Steenackers A Novel Line-Scan Algorithm for Unsynchronised Dynamic Measurements Applied Sciences non-destructive inspections dynamic line-scan thermography ultraviolet measurements dynamic measurements multispectral imaging |
| title | A Novel Line-Scan Algorithm for Unsynchronised Dynamic Measurements |
| title_full | A Novel Line-Scan Algorithm for Unsynchronised Dynamic Measurements |
| title_fullStr | A Novel Line-Scan Algorithm for Unsynchronised Dynamic Measurements |
| title_full_unstemmed | A Novel Line-Scan Algorithm for Unsynchronised Dynamic Measurements |
| title_short | A Novel Line-Scan Algorithm for Unsynchronised Dynamic Measurements |
| title_sort | novel line scan algorithm for unsynchronised dynamic measurements |
| topic | non-destructive inspections dynamic line-scan thermography ultraviolet measurements dynamic measurements multispectral imaging |
| url | https://www.mdpi.com/2076-3417/14/1/235 |
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