This was a small project testing how well it would work to detect a user's exhales using an off the shelf microphone while also filtering out environmental noise and other human voices.
I researched some of the methods for detecting breath outlined in a variety of research papers and coded an application to look for frequency spectrum peaks in the range appropriate for breath detection while filtering out other frequency ranges.
Results
As seen in the video below and my subtle contentment at the end :), the application was able to detect breath and did not signal a false positive when the user was speaking.
Role
Developer