title: Evaluation of a video-based measure of driver heart rate.
abstract: BACKGROUND
  Internal driver events such as emotional arousal do not consistently elicit observable behaviors. However, heart rate (HR) offers promise as a surrogate measure for predicting these states in drivers. Imaging photoplethysmography (IPPG) can measure HR from face video recorded in static, indoor settings, but has yet to be examined in an in-vehicle driving environment.
  
  
  METHODS
  Participants (N=10) completed an on-road driving task whilst wearing a commercial, chest-strap style heart rate monitor ("baseline"). IPPG was applied to driver face video to estimate HR and the two measures of HR were compared.
  
  
  RESULTS
  For 4 of 10 participants, IPPG produced a valid HR signal (±5 BPM of baseline) between 48 and 75% of trip duration. For the remaining participants, IPPG accuracy was poor (<20%).
  
  
  CONCLUSIONS
  In-vehicle IPPG is achievable, but significant challenges remain.
  
  
  CONCLUSIONS
  The relationship between IPPG accuracy and various confounding factors was quantified for future refinement.
authors.affiliation: Monash University Accident Research Centre (MUARC), Monash University, Australia. Electronic address: jonny.kuo@monash.edu.
authors.forename: Jonny
authors.initials: J
authors.lastname: Kuo
authors.affiliation: Monash University Accident Research Centre (MUARC), Monash University, Australia.
authors.forename: Sjaan
authors.initials: S
authors.lastname: Koppel
authors.affiliation: Monash University Accident Research Centre (MUARC), Monash University, Australia.
authors.forename: Judith L
authors.initials: JL
authors.lastname: Charlton
authors.affiliation: Human Factors North, Inc., 174 Spadina Avenue, Suite 202, Toronto, Ontario, Canada.
authors.forename: Christina M
authors.initials: CM
authors.lastname: Rudin-Brown
mesh_terms: D000328:Adult; D000368:Aged; D001288:Attention; D001334:Automobile Driving / Q000523:psychology; D001519:Behavior; D004644:Emotions; D004777:Environment; D005145:Face; D005260:Female; D006339:Heart Rate; D006801:Humans; D008297:Male; D018670:Monitoring, Ambulatory; D018986:Motor Vehicles; D017156:Photoplethysmography / Q000379:methods*; D015203:Reproducibility of Results; D014741:Video Recording / Q000379:methods*
keywords: Cognitive distraction; Cognitive workload; Computer vision; Heart rate; Photoplethysmography