UIAcceleration filtering
- by Ilya
Hi,
I found the following piece of code in apple guidelines:
- (void)accelerometer:(UIAccelerometer*)accelerometer didAccelerate:(UIAcceleration*)acceleration
{
//Use a basic low-pass filter to only keep the gravity in the accelerometer values
accel[0] = acceleration.x * kFilteringFactor + accel[0] * (1.0 - kFilteringFactor);
accel[1] = acceleration.y * kFilteringFactor + accel[1] * (1.0 - kFilteringFactor);
accel[2] = acceleration.z * kFilteringFactor + accel[2] * (1.0 - kFilteringFactor);
}
What does it exactly do? What is this low-pass filter?
Why do I have to apply it?
Thank you in advance.
