Android 采样频率 (Hz) 和采样周期 (µs) (HIGH_SAMPLING_RATE_SENSORS) 之间是否存在转换因子

Question

I'm retrieving sensor data by using mSensorManager.registerListener(this, mLinearAccelerometer, SAMPLINGPERIOD)

Android 12 introduced a rate-limitation on sensor data. If you call the registerListener() method, the sensor sampling rate is limited to 200 Hz . If your app tries to gather motion sensor data at a higher rate without declaring the new permission HIGH_SAMPLING_RATE_SENSORS , a SecurityException occurs.

Now, I'm a little bit confused because in registerListener, we have to define the sampling period in µs and not in Hz .

If I'm using values for SAMPLINGPERIOD < 5000, the abovementioned exception occurs: java.lang.SecurityException: To use the sampling rate of 4999 microseconds, app needs to declare the normal permission HIGH_SAMPLING_RATE_SENSORS.

Does this mean that a sampling rate of 200 Hz is equivalent to a sampling period of 5'000 microseconds used in registerListener? Or is this sensor-dependent?

Thanks!

Answer 1

也许，我刚刚找到了答案：5'000 µs 是 0.005 秒，即我们每秒有 200 个事件 (1/0.005)，即 200 Hz。

Answer 2

Yes, SENSOR_DELAY_FASTEST requires the new HIGH_SAMPLING_RATE_SENSORS permission. The other constants don't require it. If your code uses a flexible integer definition as SAMPLINGPERIOD, you'll need the permission as soon as you go below 5'000 µs.