02-03-2020, 10:10 AM
100ms is precise enough? Then I misinterpreted your "Resolution should be most excat." and we were talking about different time scales.
Our acoustic stopwatch gives a resolution of 1ms and theoretically, it could even be more precise as the microphone samples at 48000 Hz, resulting in a period of 21µs. In practice sound does not instantly push a single sample above the threshold, so you need a good setup to even achieve 1ms. What I wrote above applies if you want to achieve a resolution better than 20ms.
If 100ms is sufficient, I can easily check for each sample packet if its maximum is above the threshold. The resolution would depend on the buffer size of your phone, but it should be at least 100ms.
I will see if I can set up something in the next few days.
BTW: I do not see how a FFT would help here..? Do you need to filter a specific frequency range?
Our acoustic stopwatch gives a resolution of 1ms and theoretically, it could even be more precise as the microphone samples at 48000 Hz, resulting in a period of 21µs. In practice sound does not instantly push a single sample above the threshold, so you need a good setup to even achieve 1ms. What I wrote above applies if you want to achieve a resolution better than 20ms.
If 100ms is sufficient, I can easily check for each sample packet if its maximum is above the threshold. The resolution would depend on the buffer size of your phone, but it should be at least 100ms.
I will see if I can set up something in the next few days.
BTW: I do not see how a FFT would help here..? Do you need to filter a specific frequency range?