FOSDEM Helper 对比 iSmartESA 的使用情况和统计数据

Sound acquisition is endlessly done from the smartphone's built-in microphone or external microphone at a sampling frequency of 44100Hz, and the last 20 seconds are recorded when the recording button is pressed. The frequency display range can be selected from 0-500Hz, 0-1kHz, 0-2kHz, 0-5kHz, 0-10kHz, and 0-20kHz. Analysis: Waveform (time axis expansion and contraction, envelope), FFT spectrum. In case of voice sound analysis, the app can determine the fundamental frequency (by cepstrum) and formant frequencies (by MEM). In addition to being able to select any section for these analyzes, it is also possible to observe while playing back the sound. Sound pressure level and frequency: During measurement, the moving average sound pressure level for one second is displayed (A-weighted value). This function may be used to measure environmental noise. The value is adjusted for a specific microphone: SONY ECM-SP10, but the accuracy is not guaranteed. Also, during the measurement, the peak frequency (The frequency range to be detected is set on the setting screen) is displayed. Files: You can save the recorded sound as a file with comments. Sharing function is available.