HSSIM: An Objective Haptic Quality Assessment Measure for Force-Feedback Signals

Recent advances in haptic communication cast light onto the promise of full immersion into remote real or virtual environments. The quality of compressed haptic signals is crucial to fulfill this promise. Traditionally, the quality of haptic signals is evaluated through a series of subjective experiments. So far, only very limited attention was directed toward developing objective quality measures for haptic communication. As touch applications continue to grow, the need for efficient haptic quality assessment (HQA) measures is becoming more pronounced. In this work, we attempt to pragmatically approach this problem inspired by recent advances in the visual domain. More specifically, we design a HQA measure based on our knowledge of human haptic perception represented by Stevens power law and a similarity comparison between a reference and a compressed haptic force-feedback signal represented by the SSIM index as a full-reference quality measure. The proposed HSSIM measure provides clear advantages over existing approaches. We validate the performance of the proposed HQA measure with subjective experiments which show high correlation with human quality assessment results.