An Approach to Pitch Based Implementation of Non-verbal Vocal Interaction (NVVI)

Non-verbal vocal interaction (NVVI) allows people to use non-speech as an interaction technique. Many forms of NVVI exist, including humming, whistling, and tongue clicking, but the quantity of existing research is limited and high in variety. This work at-tempts to bridge the field and provides a large-scale study exploring the usability of a pitch-based NVVI system using a relative pitch approach. The study tasked users with controlling an HTML slider with the NVVI technique by humming and whistling. Findings show that users perform better with humming than whistling. Notable phenomena occurring during interactions, including vocal scrolling and overshooting, are explored.