SecurePose: Automated Face Blurring and Human Movement Kinematics
  Extraction from Videos Recorded in Clinical Settings
Rishabh Bajpai Bhooma Aravamuthan
Movement disorders are typically diagnosed by consensus-based expert
evaluation of clinically acquired patient videos. However, such broad sharing
of patient videos poses risks to patient privacy. Face blurring can be used to
de-identify videos, but this process is often manual and time-consuming.
Available automated face blurring techniques are subject to either excessive,
inconsistent, or insufficient facial blurring - all of which can be disastrous
for video assessment and patient privacy. Furthermore, assessing movement
disorders in these videos is often subjective. The extraction of quantifiable
kinematic features can help inform movement disorder assessment in these
videos, but existing methods to do this are prone to errors if using
pre-blurred videos. We have developed an open-source software called SecurePose
that can both achieve reliable face blurring and automated kinematic extraction
in patient videos recorded in a clinic setting using an iPad. SecurePose,
extracts kinematics using a pose estimation method (OpenPose), tracks and
uniquely identifies all individuals in the video, identifies the patient, and
performs face blurring. The software was validated on gait videos recorded in
outpatient clinic visits of 116 children with cerebral palsy. The validation
involved assessing intermediate steps of kinematics extraction and face
blurring with manual blurring (ground truth). Moreover, when SecurePose was
compared with six selected existing methods, it outperformed other methods in
automated face detection and achieved ceiling accuracy in 91.08% less time than
a robust manual face blurring method. Furthermore, ten experienced researchers
found SecurePose easy to learn and use, as evidenced by the System Usability
Scale. The results of this work validated the performance and usability of
SecurePose on clinically recorded gait videos for face blurring and kinematics
extraction.