Figure 2

Pre- and post-processing waveforms. A single swallow simultaneously recorded with both a microphone and dual axis accelerometer. The top graph is the signal recorded by the microphone while the middle graph is from the anterior-posterior accelerometer axis and the bottom is from the superior-inferior axis. Part (a) shows the raw device outputs while part (b) shows the same signals after our filtering techniques are applied. One can see obvious differences between sound and vibratory signals as well as different vibration directions.