{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T21:15:15Z","timestamp":1792790115263,"version":"4.5.0"},"reference-count":40,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2026,9,26]],"date-time":"2026-09-26T00:00:00Z","timestamp":1790380800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Institute of Information & Communications Technology Planning & Evaluation","award":["IITP-2026-RS-2026-25615995"],"award-info":[{"award-number":["IITP-2026-RS-2026-25615995"]}],"id":[{"id":"https:\/\/ror.org\/01g0hqq23","id-type":"ROR","asserted-by":"crossref"}]},{"award":["IITP-2026-RS-2026-25615995"],"award-info":[{"award-number":["IITP-2026-RS-2026-25615995"]}],"id":[{"id":"https:\/\/ror.org\/01g0hqq23","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Remote photoplethysmography (rPPG) estimates pulse signals from facial videos, but motion, illumination variation, exposure control, and compression can distort the waveform used for heart-rate (HR) estimation. The Plane-Orthogonal-to-Skin (POS) waveform provides an observed physiological source that often preserves recording-specific periodic structure. Existing methods commonly regress the complete waveform directly or reconstruct it from a stochastic state without using this source as the starting point. We propose PulsePath, a two-stage framework that transports POS toward paired-contact photoplethysmography (PPG) and models only the residual remaining after deterministic inference. Stage A performs conditional Flow Matching (FM) from POS using a six-channel multiscale spatiotemporal map and a 25-channel recording-level frequency representation. Stage B fixes the deterministic FM estimate and reconstructs its remaining error with variance-preserving residual diffusion and velocity prediction. In intra-dataset testing, PulsePath achieves mean absolute error (MAE), root mean square error (RMSE), and Pearson correlation values of 0.46\/0.94\/0.99 on PURE and 0.29\/0.80\/0.99 on UBFC-rPPG. In cross-dataset testing, PulsePath achieves an MAE\/RMSE of 0.23\/0.63 when trained on UBFC-rPPG and tested on PURE, and 1.13\/2.49 when trained on PURE and tested on UBFC-rPPG. The additional analyses show protocol-dependent component effects and training-run variability; the reported HR results do not establish waveform fidelity.<\/jats:p>","DOI":"10.3390\/s26196105","type":"journal-article","created":{"date-parts":[[2026,9,28]],"date-time":"2026-09-28T15:57:57Z","timestamp":1790611077000},"page":"6105","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["PulsePath: Two-Stage Generative Waveform Refinement for Robust Remote Photoplethysmography Estimation"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0009-0006-1916-3282","authenticated-orcid":false,"given":"Juha","family":"Park","sequence":"first","affiliation":[{"name":"Division of Electronic Engineering, Jeonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonju 54896, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-4544-0761","authenticated-orcid":false,"given":"Seungmin","family":"Oh","sequence":"additional","affiliation":[{"name":"Division of Electronic Engineering, Jeonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonju 54896, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"software","vocabulary":"credit"},{"role":"validation","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9312-6299","authenticated-orcid":false,"given":"Sang Jun","family":"Lee","sequence":"additional","affiliation":[{"name":"Division of Electronic Engineering, Jeonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonju 54896, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"supervision","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"21434","DOI":"10.1364\/OE.16.021434","article-title":"Remote plethysmographic imaging using ambient light","volume":"16","author":"Verkruysse","year":"2008","journal-title":"Opt. 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