Schlieren imaging and video classification of alphabet pronunciations: exploiting phonetic flows for speech recognition and speech therapy

Visual Computing for Industry Biomedicine and Art, Journal Year: 2024, Volume and Issue: 7(1)

Published: May 22, 2024

Abstract Speech is a highly coordinated process that requires precise control over vocal tract morphology/motion to produce intelligible sounds while simultaneously generating unique exhaled flow patterns. The schlieren imaging technique visualizes airflows with subtle density variations. It hypothesized speech flows captured by schlieren, when analyzed using hybrid of convolutional neural network (CNN) and long short-term memory (LSTM) network, can recognize alphabet pronunciations, thus facilitating automatic recognition disorder therapy. This study evaluates the feasibility CNN-based video classification differentiate corresponding first four alphabets: /A/, /B/, /C/, /D/. A optical system was developed, pronunciations were recorded for two participants at an acquisition rate 60 frames per second. total 640 clips, each lasting 1 s, utilized train test CNN-LSTM network. Acoustic analyses conducted understand phonetic differences among alphabets. trained separately on datasets varying sizes (i.e., 20, 30, 40, 50 videos alphabet), all achieving 95% accuracy in classifying same participant. However, network’s performance declined tested from different participant, dropping around 44%, indicating significant inter-participant variability pronunciation. Retraining both improved 93% second Analysis misclassified indicated factors such as low quality disproportional head size affected accuracy. These results highlight potential CNN-assisted therapy articulation flows, although challenges remain expanding set participant cohort.

Language: Английский

Visualization and Quantification of Facemask Leakage Flows and Interpersonal Transmission with Varying Face Coverings

Published: June 7, 2024

Although mask-wearing is now widespread, knowledge of how to quantify or improve its performance remains surprisingly limited and largely based on empirical evidence. The objective this study was visualize the expiratory airflows from facemasks evaluate aerosol transmission between two persons. Different visualization methods were explored, including Schlieren optical system, laser/LED-particle imaging thermal camera, vapor-SarGel system. leakage flows escaped aerosols quantified using a hotwire anemometer particle counter, respectively. results show that reduces exhaled flow velocity 2~4 m/s (with no facemask) around 0.1 m/s, thus decreasing droplet speeds. Cloth, surgical, KN95 masks showed varying at nose top, sides, chin. rate also differed inhalation exhalation. neck gaiter has low filtration efficiency high fractions, providing protection efficiency. There considerable deposition in mouth-nose area, as well neck, chin, jaw, which heightened risk self-inoculation through spontaneous face-touching. A face shield plus surgical mask greatly reduced droplets head, face, indicating double coverings can be highly effective when single insufficient. system provided practical approach interpersonal under close contact scenarios with different coverings.

Language: Английский

Visualization and Quantification of Facemask Leakage Flows and Interpersonal Transmission with Varying Face Coverings

Fluids, Journal Year: 2024, Volume and Issue: 9(7), P. 166 - 166

Published: July 22, 2024

Although mask-wearing is now widespread, the knowledge of how to quantify or improve their performance remains surprisingly limited and largely based on empirical evidence. The objective this study was visualize expiratory airflows from facemasks evaluate aerosol transmission between two persons. Different visualization methods were explored, including Schlieren optical system, laser/LED-particle imaging thermal camera, vapor–SarGel system. leakage flows escaped aerosols quantified using a hotwire anemometer particle counter, respectively. results show that reduces exhaled flow velocity 2~4 m/s (with no facemask) around 0.1 m/s, thus decreasing droplet speeds. Cloth, surgical, KN95 masks showed varying at nose top, sides, chin. rate also differed inhalation exhalation. neck gaiter has low filtration efficiency high fractions, providing protection efficiency. There considerable deposition in mouth–nose area, as well neck, chin, jaw, which heightened risk self-inoculation through spontaneous face-touching. A face shield plus surgical mask greatly reduced droplets head, face, indicating double coverings can be highly effective when single insufficient. system provided practical approach interpersonal under close contact scenarios with different coverings.

Language: Английский