Detection and segmentation for chromosphere brightpoints by CLPNet

Detection and segmentation for chromosphere brightpoints by CLPNet | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Detection and segmentation for chromosphere brightpoints by CLPNet xichen Zhang, Yunfei Yang, Xiaoli Zhang, Song Feng, Wei Dai, Bo Liang, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7269919/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 24 Mar, 2026 Read the published version in Solar Physics → Version 1 posted 7 You are reading this latest preprint version Abstract Chromosphere bright points (CBPs) are small and bright magnetic structures, which are the reflection of the cross sections of the magnetic flux tubes crossing the chromosphere. Accurate detection and segmentation of CBPs enable large-scale data acquisition and then feature extraction. In this paper, we propose the CLPNet model based on the LPNet architecture. By restructuring the global feature extractor and patch network module, we improve the segmentation accuracy and small-object detection. The Ca II H image-series in the quiet regions from the Solar Optical Telescope (SOT) on board Hinode are used to construct a training set containing about 2800 CBPs and two test sets both containing about 1200 CBPs. The precision, recall, F1-score are 0.840, 0.831 and 0.835, respectively. For the segmentation effect at the pixel level, the pixel precision, pixel recall and pixel F1-score and mIoU value are 0.751, 0.713, 0.732 and 0.637, respectively. This indicates that CLPNet demonstrates a commendable level of efficiency and accuracy in both detection and segmentation tasks. The compactness is used for classifying the morphology of CBPs. Specifically, CBPs exhibiting compactness less than or equal to 1.13 are regarded as point-like CBPs, which could correspond to a single slender flux tube. Otherwise, CBPs are regarded as non-point-like CBPs, which could correspond to the interaction of several slender flux tubes. There are differences in features between point-like and non-point-like CBPs. The mean compactnesses are 1.06±0.04 and 1.20±0.07, respectively. The mean equivalent diameters are 201±50 and 279±60 km, respectively. The mean values of the maximum intensity contrast are 1.14±0.47 and 1.54±0.66 ⟨IQS_Ca⟩, respectively. The mean values of eccentricity are 0.60±0.14 and 0.78±0.11, respectively. This research provides a more precise methodology for the comprehensive study of CBPs, offering novel insights into the physical phenomena occurring on the chromosphere and then establishing a quantitative foundation for three-dimensional modeling of magnetic flux tubes and investigations into coronal heating mechanisms. Chromosphere bright points CLPNet object segmentation feature statistics Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 24 Mar, 2026 Read the published version in Solar Physics → Version 1 posted Editorial decision: Revision requested 18 Sep, 2025 Reviews received at journal 17 Sep, 2025 Reviewers agreed at journal 27 Aug, 2025 Reviewers invited by journal 21 Aug, 2025 Editor assigned by journal 02 Aug, 2025 Submission checks completed at journal 02 Aug, 2025 First submitted to journal 01 Aug, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7269919","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":506499655,"identity":"42cf6891-77bc-4803-8644-893e8c5f91a2","order_by":0,"name":"xichen Zhang","email":"","orcid":"","institution":"Kunming University of Science and Technology","correspondingAuthor":false,"prefix":"","firstName":"xichen","middleName":"","lastName":"Zhang","suffix":""},{"id":506499656,"identity":"5b9bdfa9-d536-4b88-8421-a3f83b3812f1","order_by":1,"name":"Yunfei 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Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Chromosphere bright points, CLPNet, object segmentation, feature statistics","lastPublishedDoi":"10.21203/rs.3.rs-7269919/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7269919/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"Chromosphere bright points (CBPs) are small and bright magnetic structures, which are the reflection of the cross sections of the magnetic flux tubes crossing the chromosphere. Accurate detection and segmentation of CBPs enable large-scale data acquisition and then feature extraction. In this paper, we propose the CLPNet model based on the LPNet architecture. By restructuring the global feature extractor and patch network module, we improve the segmentation accuracy and small-object detection. The Ca II H image-series in the quiet regions from the Solar Optical Telescope (SOT) on board Hinode are used to construct a training set containing about 2800 CBPs and two test sets both containing about 1200 CBPs. The precision, recall, F1-score are 0.840, 0.831 and 0.835, respectively. For the segmentation effect at the pixel level, the pixel precision, pixel recall and pixel F1-score and mIoU value are 0.751, 0.713, 0.732 and 0.637, respectively. This indicates that CLPNet demonstrates a commendable level of efficiency and accuracy in both detection and segmentation tasks.\nThe compactness is used for classifying the morphology of CBPs. Specifically, CBPs exhibiting compactness less than or equal to 1.13 are regarded as point-like CBPs, which could correspond to a single slender flux tube. Otherwise, CBPs are regarded as non-point-like CBPs, which could correspond to the interaction of several slender flux tubes. There are differences in features between point-like and non-point-like CBPs. The mean compactnesses are 1.06±0.04 and 1.20±0.07, respectively. The mean equivalent diameters are 201±50 and 279±60 km, respectively. The mean values of the maximum intensity contrast are 1.14±0.47 and 1.54±0.66 ⟨IQS_Ca⟩, respectively. The mean values of eccentricity are 0.60±0.14 and 0.78±0.11, respectively. This research provides a more precise methodology for the comprehensive study of CBPs, offering novel insights into the physical phenomena occurring on the chromosphere and then establishing a quantitative foundation for three-dimensional modeling of magnetic flux tubes and investigations into coronal heating mechanisms.","manuscriptTitle":"Detection and segmentation for chromosphere brightpoints by CLPNet","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-08-29 06:47:14","doi":"10.21203/rs.3.rs-7269919/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-09-18T11:13:27+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-09-17T05:02:20+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"276057886273458287101506073872136147609","date":"2025-08-27T16:54:26+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-08-21T14:39:30+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-08-02T16:29:06+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-08-02T16:28:14+00:00","index":"","fulltext":""},{"type":"submitted","content":"Solar Physics","date":"2025-08-01T09:38:46+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"solar-physics","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"sola","sideBox":"Learn more about [Solar Physics](http://link.springer.com/journal/11207)","snPcode":"11207","submissionUrl":"https://submission.nature.com/new-submission/11207/3","title":"Solar Physics","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"167a43aa-22b3-4b6a-9c35-decc2acaaf5d","owner":[],"postedDate":"August 29th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2026-03-30T16:34:27+00:00","versionOfRecord":{"articleIdentity":"rs-7269919","link":"https://doi.org/10.1007/s11207-026-02638-w","journal":{"identity":"solar-physics","isVorOnly":false,"title":"Solar Physics"},"publishedOn":"2026-03-24 16:10:56","publishedOnDateReadable":"March 24th, 2026"},"versionCreatedAt":"2025-08-29 06:47:14","video":"","vorDoi":"10.1007/s11207-026-02638-w","vorDoiUrl":"https://doi.org/10.1007/s11207-026-02638-w","workflowStages":[]},"version":"v1","identity":"rs-7269919","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7269919","identity":"rs-7269919","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}