A Comparison of Data-Filtering Methods Obtained Using Different Machine-Learning Models for Head Detection during vHIT Recordings on a Smartphone Camera
摘要
The problem of increasing the accuracy of determining the position of a patient’s head during the vHIT medical test using video recordings obtained from a smartphone camera is considered. The focus is on comparing the output of three machine-learning models (Dense Head Pose Estimation, Head Pose Estimation, and Lightweight Head Pose Estimation) designed for head pose detection with reference data obtained using IMU sensors. To improve the accuracy of signals obtained from a video stream, four digital filtering methods were compared, namely, empirical mode decomposition (EMD), variational mode decomposition (VMD), discrete wavelet transform, and Butterworth filtering. The mean square error (MSE), weighted by the signal amplitude, was used as a quality metric. The results showed that the best fit to the benchmark data was achieved by using the LHPE model in combination with the wavelet transform and Butterworth filtering. The presented approach confirms the feasibility of using a smartphone camera for high-precision head detection, which opens up the prospect of using ordinary smartphones as hardware for the vHIT test.