A Dynamic Threshold-Based Method for Robust and Accurate Blink Detection in Eye-Tracking Data | 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 A Dynamic Threshold-Based Method for Robust and Accurate Blink Detection in Eye-Tracking Data Mohammad Ahsan Khodami This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7759033/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Blink detection is a critical component of eye-tracking research, particularly in pupillometry, where data loss due to blinks can obscure meaningful insights. Existing methods often rely on fixed thresholds or device-specific noise profiles, which may lead to inaccuracies in detecting blink onsets and offsets, especially in heterogeneous datasets. This study introduces a novel blink detection model that dynamically adapts to varying pupil size distributions, ensuring robustness across different experimental conditions. The proposed method integrates dynamic thresholding, which adjusts based on the mean pupil size of valid samples, Gaussian smoothing, which reduces noise while preserving signal integrity, and adaptive boundary refinement, which refines blink onsets and offsets based on trends in the smoothed data. Unlike traditional approaches that merge closely spaced blinks, this model treats each blink as an independent event, preserving temporal resolution, which is essential for cognitive and perceptual studies. The model is computationally efficient and adaptable to a wide range of sampling rates, from low-frequency (e.g., 250 Hz) to high-frequency (e.g., 2000 Hz) data, ensuring consistent blink detection across different eye-tracking setups. This makes it suitable for both real-time and offline eye-tracking applications. Experimental evaluations demonstrate its ability to accurately detect blinks across diverse datasets. By offering a more reliable and generalizable solution, this model advances blink detection methodologies and enhances the quality of eye-tracking data analysis across research domains. Blink detection pupillometry eye-tracking dynamic thresholding Gaussian smoothing Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted 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. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-7759033","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":533075852,"identity":"684da2b9-2c07-4d87-870f-c1fe2bb4436d","order_by":0,"name":"Mohammad Ahsan Khodami","email":"data:image/png;base64,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","orcid":"","institution":"University of Padua","correspondingAuthor":true,"prefix":"","firstName":"Mohammad","middleName":"Ahsan","lastName":"Khodami","suffix":""}],"badges":[],"createdAt":"2025-10-01 11:23:27","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7759033/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7759033/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":94254356,"identity":"61d74638-02f9-4c3c-af72-668b5aa1ea60","added_by":"auto","created_at":"2025-10-24 07:30:09","extension":"json","order_by":0,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":4433,"visible":true,"origin":"","legend":"","description":"","filename":"d7dde02538464d059c0670dbc00d7d67.json","url":"https://assets-eu.researchsquare.com/files/rs-7759033/v1/d6cc886ff478d1352e12adac.json"},{"id":94254355,"identity":"011e0f28-817a-4970-8e7f-a10f3130550a","added_by":"auto","created_at":"2025-10-24 07:30:08","extension":"xml","order_by":1,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":87853,"visible":true,"origin":"","legend":"","description":"","filename":"d7dde02538464d059c0670dbc00d7d671enriched.xml","url":"https://assets-eu.researchsquare.com/files/rs-7759033/v1/317da9b82d9ffe8c4eadf896.xml"},{"id":94254334,"identity":"2df11618-a218-4186-96a8-820a3403aa11","added_by":"auto","created_at":"2025-10-24 07:30:06","extension":"pdf","order_by":2,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":7373990,"visible":true,"origin":"","legend":"","description":"","filename":"GBdynamicblinkdetection.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7759033/v1/af82706f8da39d051ea96ea5.pdf"},{"id":94254354,"identity":"1cc3035b-39fd-4ec5-9c89-6c6e29b5eabb","added_by":"auto","created_at":"2025-10-24 07:30:08","extension":"png","order_by":3,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":3805332,"visible":true,"origin":"","legend":"","description":"","filename":"allsteps.png","url":"https://assets-eu.researchsquare.com/files/rs-7759033/v1/9e3aa2482c05331c70465ff5.png"},{"id":94254329,"identity":"5885130f-1f02-475a-a859-3fd517abd881","added_by":"auto","created_at":"2025-10-24 07:30:06","extension":"eps","order_by":4,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":2890,"visible":true,"origin":"","legend":"","description":"","filename":"empty.eps","url":"https://assets-eu.researchsquare.com/files/rs-7759033/v1/ec24c3d7a4ae588ddc9706b4.eps"},{"id":94254346,"identity":"bbefce1b-064e-41f1-9f95-25a5bd34d110","added_by":"auto","created_at":"2025-10-24 07:30:07","extension":"eps","order_by":5,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":91593,"visible":true,"origin":"","legend":"","description":"","filename":"fig.eps","url":"https://assets-eu.researchsquare.com/files/rs-7759033/v1/0cfc678c1cde466b9f1761f2.eps"},{"id":94254331,"identity":"bd0e6841-46c9-4935-a3ce-d680d95870c0","added_by":"auto","created_at":"2025-10-24 07:30:06","extension":"png","order_by":6,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":1034035,"visible":true,"origin":"","legend":"","description":"","filename":"plot1.png","url":"https://assets-eu.researchsquare.com/files/rs-7759033/v1/b62241477c1cb9a8e1ff5e92.png"},{"id":94254826,"identity":"4428db40-95d3-4c34-a3bb-815da18306b3","added_by":"auto","created_at":"2025-10-24 07:38:08","extension":"png","order_by":7,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":770933,"visible":true,"origin":"","legend":"","description":"","filename":"plotextreme.png","url":"https://assets-eu.researchsquare.com/files/rs-7759033/v1/f1c631ee2a4eb7fc463806e1.png"},{"id":94254330,"identity":"76aa544a-1828-41cb-96df-42c7a6687625","added_by":"auto","created_at":"2025-10-24 07:30:06","extension":"png","order_by":8,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":1163402,"visible":true,"origin":"","legend":"","description":"","filename":"pupilsizewithonsetsoffsets.png","url":"https://assets-eu.researchsquare.com/files/rs-7759033/v1/1101955576339b3dd89b3e53.png"},{"id":94254352,"identity":"17882bb9-dcdb-4bc5-bf89-2f5afb4ae98b","added_by":"auto","created_at":"2025-10-24 07:30:08","extension":"png","order_by":9,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":1130441,"visible":true,"origin":"","legend":"","description":"","filename":"pupilsizewithonsetsoffsets2.png","url":"https://assets-eu.researchsquare.com/files/rs-7759033/v1/9188345c17a383d099fc758a.png"},{"id":94254335,"identity":"60968e96-0b26-43ed-b452-5a2ec5f502ae","added_by":"auto","created_at":"2025-10-24 07:30:06","extension":"bst","order_by":10,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":147148,"visible":true,"origin":"","legend":"","description":"","filename":"snapacite.bst","url":"https://assets-eu.researchsquare.com/files/rs-7759033/v1/3d86f32dcd316b014390159b.bst"},{"id":94254336,"identity":"de546583-3ccc-41ce-8f20-22893a2357b6","added_by":"auto","created_at":"2025-10-24 07:30:06","extension":"bst","order_by":11,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":30423,"visible":true,"origin":"","legend":"","description":"","filename":"snaps.bst","url":"https://assets-eu.researchsquare.com/files/rs-7759033/v1/7789368ad0d11528014247ae.bst"},{"id":94254338,"identity":"89b6586a-11d7-4bba-839a-7b82b6dcbabc","added_by":"auto","created_at":"2025-10-24 07:30:07","extension":"pdf","order_by":12,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":390370,"visible":true,"origin":"","legend":"","description":"","filename":"snarticle.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7759033/v1/5e4a986978699a53366ccfbc.pdf"},{"id":94254823,"identity":"b9563ffd-343f-491d-b5ac-8d24b0dc5300","added_by":"auto","created_at":"2025-10-24 07:38:07","extension":"bst","order_by":13,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":35733,"visible":true,"origin":"","legend":"","description":"","filename":"snbasic.bst","url":"https://assets-eu.researchsquare.com/files/rs-7759033/v1/4a65f56cbcd381fed587a37d.bst"},{"id":94254342,"identity":"e3558219-f4ed-4302-a25b-02c4d832887d","added_by":"auto","created_at":"2025-10-24 07:30:07","extension":"bst","order_by":14,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":40398,"visible":true,"origin":"","legend":"","description":"","filename":"snchicago.bst","url":"https://assets-eu.researchsquare.com/files/rs-7759033/v1/7ad9f24338fb0077e7ead0b2.bst"},{"id":94254350,"identity":"ef1d0dda-a038-47ac-8c66-09a7154e5a98","added_by":"auto","created_at":"2025-10-24 07:30:08","extension":"cls","order_by":15,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":55331,"visible":true,"origin":"","legend":"","description":"","filename":"snjnl.cls","url":"https://assets-eu.researchsquare.com/files/rs-7759033/v1/0ef64aad0224ebf8357111d2.cls"},{"id":94254351,"identity":"9fe4c3e2-f0c5-4f88-ae5c-047777a60644","added_by":"auto","created_at":"2025-10-24 07:30:08","extension":"bst","order_by":16,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":64140,"visible":true,"origin":"","legend":"","description":"","filename":"snmathphysay.bst","url":"https://assets-eu.researchsquare.com/files/rs-7759033/v1/089a68065bf7396accfc3c3e.bst"},{"id":94254348,"identity":"3ba85aef-6548-42b4-8b55-84fdbfc55507","added_by":"auto","created_at":"2025-10-24 07:30:07","extension":"bst","order_by":17,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":64141,"visible":true,"origin":"","legend":"","description":"","filename":"snmathphysnum.bst","url":"https://assets-eu.researchsquare.com/files/rs-7759033/v1/f427bcfffa333fcf0a6d1bed.bst"},{"id":94254825,"identity":"f6173943-d522-4711-9476-25efe08bb41c","added_by":"auto","created_at":"2025-10-24 07:38:07","extension":"bst","order_by":18,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":38349,"visible":true,"origin":"","legend":"","description":"","filename":"snnature.bst","url":"https://assets-eu.researchsquare.com/files/rs-7759033/v1/726b6e56c6b523d58e9882d0.bst"},{"id":94254821,"identity":"2b8dce8c-46b9-4edb-8efd-dc506b391583","added_by":"auto","created_at":"2025-10-24 07:38:06","extension":"bst","order_by":19,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":41304,"visible":true,"origin":"","legend":"","description":"","filename":"snvancouver.bst","url":"https://assets-eu.researchsquare.com/files/rs-7759033/v1/41c26b7cd247e8d20d73cc81.bst"},{"id":94254822,"identity":"dba8a669-ceb3-42e2-be32-021abfa7e95a","added_by":"auto","created_at":"2025-10-24 07:38:07","extension":"png","order_by":20,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":606214,"visible":true,"origin":"","legend":"","description":"","filename":"step1.png","url":"https://assets-eu.researchsquare.com/files/rs-7759033/v1/79d2aadc83e32c5c991e2b27.png"},{"id":94254332,"identity":"6a88d2e9-fcb0-4ce7-858f-a1b819ad67c8","added_by":"auto","created_at":"2025-10-24 07:30:06","extension":"png","order_by":21,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":482868,"visible":true,"origin":"","legend":"","description":"","filename":"step2.png","url":"https://assets-eu.researchsquare.com/files/rs-7759033/v1/51c9f63d17ebc5e2cd4fabf6.png"},{"id":94254820,"identity":"9abda048-cfe7-4417-bcf7-c60440946b44","added_by":"auto","created_at":"2025-10-24 07:38:06","extension":"png","order_by":22,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":625390,"visible":true,"origin":"","legend":"","description":"","filename":"step3.png","url":"https://assets-eu.researchsquare.com/files/rs-7759033/v1/bd027d303c1e653a82dbc96e.png"},{"id":94254341,"identity":"59c12632-cd85-4850-a0ec-3efa2687d5f4","added_by":"auto","created_at":"2025-10-24 07:30:07","extension":"png","order_by":23,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":698918,"visible":true,"origin":"","legend":"","description":"","filename":"step4.png","url":"https://assets-eu.researchsquare.com/files/rs-7759033/v1/5f2af6d5e282e94a1dbef042.png"},{"id":94254343,"identity":"9c491a16-913a-45e3-abc6-647b05f615f4","added_by":"auto","created_at":"2025-10-24 07:30:07","extension":"png","order_by":24,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":638932,"visible":true,"origin":"","legend":"","description":"","filename":"step5.png","url":"https://assets-eu.researchsquare.com/files/rs-7759033/v1/299c9dfc73df17609a571d03.png"},{"id":94254824,"identity":"c2e6d814-bfc6-4ec1-b4e0-93f14f66db59","added_by":"auto","created_at":"2025-10-24 07:38:07","extension":"png","order_by":25,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":658050,"visible":true,"origin":"","legend":"","description":"","filename":"step6.png","url":"https://assets-eu.researchsquare.com/files/rs-7759033/v1/d9dde4f6fcce6e0f6b105c7f.png"},{"id":94254339,"identity":"7be3ef4e-6ea5-46ec-989f-abe88a198943","added_by":"auto","created_at":"2025-10-24 07:30:07","extension":"xml","order_by":31,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":94985,"visible":true,"origin":"","legend":"","description":"","filename":"d7dde02538464d059c0670dbc00d7d671structuring.xml","url":"https://assets-eu.researchsquare.com/files/rs-7759033/v1/37c93c8c38cda3a3f2fd250f.xml"},{"id":94254344,"identity":"00f6c190-3e78-4121-97df-2bc3f9cc9b91","added_by":"auto","created_at":"2025-10-24 07:30:07","extension":"html","order_by":32,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":101339,"visible":true,"origin":"","legend":"","description":"","filename":"earlyproof.html","url":"https://assets-eu.researchsquare.com/files/rs-7759033/v1/571ab0ef8b0e1ca4b8b0377e.html"},{"id":104781372,"identity":"248dcf80-78ea-4550-abf3-2512f247e5b5","added_by":"auto","created_at":"2026-03-17 07:55:33","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":9105615,"visible":true,"origin":"","legend":"","description":"","filename":"GBdynamicblinkdetection.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7759033/v1_covered_54286b25-57a4-4906-8e63-0b722c28f662.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"A Dynamic Threshold-Based Method for Robust and Accurate Blink Detection in Eye-Tracking Data","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"
[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Blink detection, pupillometry, eye-tracking, dynamic thresholding, Gaussian smoothing","lastPublishedDoi":"10.21203/rs.3.rs-7759033/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7759033/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eBlink detection is a critical component of eye-tracking research, particularly in pupillometry, where data loss due to blinks can obscure meaningful insights. Existing methods often rely on fixed thresholds or device-specific noise profiles, which may lead to inaccuracies in detecting blink onsets and offsets, especially in heterogeneous datasets. This study introduces a novel blink detection model that dynamically adapts to varying pupil size distributions, ensuring robustness across different experimental conditions. The proposed method integrates dynamic thresholding, which adjusts based on the mean pupil size of valid samples, Gaussian smoothing, which reduces noise while preserving signal integrity, and adaptive boundary refinement, which refines blink onsets and offsets based on trends in the smoothed data. Unlike traditional approaches that merge closely spaced blinks, this model treats each blink as an independent event, preserving temporal resolution, which is essential for cognitive and perceptual studies. The model is computationally efficient and adaptable to a wide range of sampling rates, from low-frequency (e.g., 250 Hz) to high-frequency (e.g., 2000 Hz) data, ensuring consistent blink detection across different eye-tracking setups. This makes it suitable for both real-time and offline eye-tracking applications. Experimental evaluations demonstrate its ability to accurately detect blinks across diverse datasets. By offering a more reliable and generalizable solution, this model advances blink detection methodologies and enhances the quality of eye-tracking data analysis across research domains.\u003c/p\u003e","manuscriptTitle":"A Dynamic Threshold-Based Method for Robust and Accurate Blink Detection in Eye-Tracking Data","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-10-24 07:29:59","doi":"10.21203/rs.3.rs-7759033/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"
[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"0e30663c-89db-46c8-b063-ab21a888b6ad","owner":[],"postedDate":"October 24th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2026-03-13T00:54:11+00:00","versionOfRecord":[],"versionCreatedAt":"2025-10-24 07:29:59","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7759033","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7759033","identity":"rs-7759033","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}
Text is read by the "Ask this paper" AI Q&A widget below.
Extraction quality varies by source — PMC NXML preserves structure
cleanly, OA-HTML may include some navigation residue, and OA-PDF can
have broken hyphenation. The publisher copy
(via DOI)
is the canonical version.