Pushing the limits of remote RF sensing by reading lips under the face mask.

The problem of Lip-reading has become an important research challenge in recent years. The goal is to recognise speech from lip movements. Most of the Lip-reading technologies developed so far are camera-based, which require video recording of the target. However, these technologies have well-known limitations of occlusion and ambient lighting with serious privacy concerns. Furthermore, vision-based technologies are not useful for multi-modal hearing aids in the coronavirus (COVID-19) environment, where face masks have become a norm. This paper aims to solve the fundamental limitations of camera-based systems by proposing a radio frequency (RF) based Lip-reading framework, having an ability to read lips under face masks. The framework employs Wi-Fi and radar technologies as enablers of RF sensing based Lip-reading. A dataset comprising of vowels A, E, I, O, U and empty (static/closed lips) is collected using both technologies, with a face mask. The collected data is used to train machine learning (ML) and deep learning (DL) models. A high classification accuracy of 95% is achieved on the Wi-Fi data utilising neural network (NN) models. Moreover, similar accuracy is achieved by VGG16 deep learning model on the collected radar-based dataset.

The McGurk effect in the time of pandemic: Age-dependent adaptation to an environmental loss of visual speech cues.

Seeing a person's mouth move for [ga] while hearing [ba] often results in the perception of "da." Such audiovisual integration of speech cues, known as the McGurk effect, is stable within but variable across individuals. When the visual or auditory cues are degraded, due to signal distortion or the perceiver's sensory impairment, reliance on cues via the impoverished modality decreases. This study tested whether cue-reliance adjustments due to exposure to reduced cue availability are persistent and transfer to subsequent perception of speech with all cues fully available. A McGurk experiment was administered at the beginning and after a month of mandatory face-mask wearing (enforced in Czechia during the 2020 pandemic). Responses to audio-visually incongruent stimuli were analyzed from 292 persons (ages 16-55), representing a cross-sectional sample, and 41 students (ages 19-27), representing a longitudinal sample. The extent to which the participants relied exclusively on visual cues was affected by testing time in interaction with age. After a month of reduced access to lipreading, reliance on visual cues (present at test) somewhat lowered for younger and increased for older persons. This implies that adults adapt their speech perception faculty to an altered environmental availability of multimodal cues, and that younger adults do so more efficiently. This finding demonstrates that besides sensory impairment or signal noise, which reduce cue availability and thus affect audio-visual cue reliance, having experienced a change in environmental conditions can modulate the perceiver's (otherwise relatively stable) general bias towards different modalities during speech communication.

Impacts of face coverings on communication: an indirect impact of COVID-19.

OBJECTIVE: To understand the impact of face coverings on hearing and communication. DESIGN: An online survey consisting of closed-set and open-ended questions distributed within the UK to gain insights into experiences of interactions involving face coverings, and of the impact of face coverings on communication. SAMPLE: Four hundred and sixty members of the general public were recruited via snowball sampling. People with hearing loss were intentionally oversampled to more thoroughly assess the effect of face coverings in this group. RESULTS: With few exceptions, participants reported that face coverings negatively impacted hearing, understanding, engagement, and feelings of connection with the speaker. Impacts were greatest when communicating in medical situations. People with hearing loss were significantly more impacted than those without hearing loss. Face coverings impacted communication content, interpersonal connectedness, and willingness to engage in conversation; they increased anxiety and stress, and made communication fatiguing, frustrating and embarrassing - both as a speaker wearing a face covering, and when listening to someone else who is wearing one. CONCLUSIONS: Face coverings have far-reaching impacts on communication for everyone, but especially for people with hearing loss. These findings illustrate the need for communication-friendly face-coverings, and emphasise the need to be communication-aware when wearing a face covering.