Gait analysis plays a pivotal role in diagnosing a spectrum of
neurological and musculoskeletal disorders. Variations in gait patterns
often serve as early indicators of underlying health conditions,
underscoring the importance of precise and timely analysis for effective
intervention and treatment. In recent years, computer vision techniques
have emerged as robust tools for automated gait analysis, offering
non-invasive, cost-effective, and scalable solutions. However, existing
approaches often overlook the critical aspect of privacy preservation.
In this study, we propose the worldâs pioneering computer vision-based
abnormal gait detection system with a privacy-preserving mechanism.
Specifically, we extract 2D skeletons from encrypted images using a deep
neural network model, which is facilitated by an optical system
incorporating a custom-made refractive optical element. These extracted
features are then fed into machine learning models for the detection of
normal versus abnormal gait patterns. Evaluations across various models
including random forest, decision tree, k-nearest neighbor, support
vector machine, neural network, and convolutional neural network reveal
that the random forest model attains the highest classification
performance based on 2D skeletons extracted from encrypted images.