Extraction of nostril regions using periodical thermal change for breath monitoring

In this paper, we propose a method to extract the nostril regions using two features; the temperature of the nostril changes synchronously with breathing, and the temperature around wing of the nose is higher than wing of the nose. Our proposed method was evaluated using 10 testees. As a result of comparison between the nostril regions obtained by manual input and the nostril regions by our proposed system, the value of the precision of 78.37% was obtained. In addition, because the appearance of the nostril regions varies depending on the position and angle to be observed, we experimented to determine the angle most suitable for extraction of the nostril regions. Experimental results showed that when the subject was measured from an angle looking up at elevation angle of 30 the precision was improved to 94.21%. Finally, in this paper we discuss the possibility of application to the automatic respiration rate measurement method using the proposed method.