Investigating Identity Signals in Conversational Facial Dynamics via Disentangled Expression Features

Fuente: arXiv
Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: Chapariniya, Masoumeh, Vuillecard, Pierre, Odobez, Jean-Marc, Dellwo, Volker, Vukovic, Teodora
Format: Preprint
Veröffentlicht: 2025
Schlagworte:
Online-Zugang:
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
_version_ 1866908589338132480
author Chapariniya, Masoumeh
Vuillecard, Pierre
Odobez, Jean-Marc
Dellwo, Volker
Vukovic, Teodora
author_facet Chapariniya, Masoumeh
Vuillecard, Pierre
Odobez, Jean-Marc
Dellwo, Volker
Vukovic, Teodora
contents This work investigates whether individuals can be identified solely through the pure dynamical components of their facial expressions, independent of static facial appearance. We leverage the FLAME 3D morphable model to achieve explicit disentanglement between facial shape and expression dynamics, extracting frame-by-frame parameters from conversational videos while retaining only expression and jaw coefficients. On the CANDOR dataset of 1,429 speakers in naturalistic conversations, our Conformer model with supervised contrastive learning achieves 61.14\%accuracy on 1,429-way classification -- 458 times above chance -- demonstrating that facial dynamics carry strong identity signatures. We introduce a drift-to-noise ratio (DNR) that quantifies the reliability of shape expression separation by measuring across-session shape changes relative to within-session variability. DNR strongly negatively correlates with recognition performance, confirming that unstable shape estimation compromises dynamic identification. Our findings reveal person-specific signatures in conversational facial dynamics, with implications for social perception and clinical assessment.
format Preprint
id arxiv_https___arxiv_org_abs_2510_11223
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Investigating Identity Signals in Conversational Facial Dynamics via Disentangled Expression Features
Chapariniya, Masoumeh
Vuillecard, Pierre
Odobez, Jean-Marc
Dellwo, Volker
Vukovic, Teodora
Computer Vision and Pattern Recognition
This work investigates whether individuals can be identified solely through the pure dynamical components of their facial expressions, independent of static facial appearance. We leverage the FLAME 3D morphable model to achieve explicit disentanglement between facial shape and expression dynamics, extracting frame-by-frame parameters from conversational videos while retaining only expression and jaw coefficients. On the CANDOR dataset of 1,429 speakers in naturalistic conversations, our Conformer model with supervised contrastive learning achieves 61.14\%accuracy on 1,429-way classification -- 458 times above chance -- demonstrating that facial dynamics carry strong identity signatures. We introduce a drift-to-noise ratio (DNR) that quantifies the reliability of shape expression separation by measuring across-session shape changes relative to within-session variability. DNR strongly negatively correlates with recognition performance, confirming that unstable shape estimation compromises dynamic identification. Our findings reveal person-specific signatures in conversational facial dynamics, with implications for social perception and clinical assessment.
title Investigating Identity Signals in Conversational Facial Dynamics via Disentangled Expression Features
topic Computer Vision and Pattern Recognition
url https://arxiv.org/abs/2510.11223