如何为iPhone加速计实现高通滤波器？

Question

我记得几天前在示例中的某个地方看到了高通滤波器的代码，但我现在无法在任何地方找到它！有人能记住我的高通滤波器实现代码的位置吗？

还是更好的发布算法？

谢谢！

Answer 1

From the idevkit.com forums:

#define kFilteringFactor 0.1 
static UIAccelerationValue rollingX=0, rollingY=0, rollingZ=0; 


- (void)accelerometer:(UIAccelerometer *)accelerometer didAccelerate:(UIAcceleration *)acceleration { 

    // Calculate low pass values 

    rollingX = (acceleration.x * kFilteringFactor) + (rollingX * (1.0 - kFilteringFactor)); 
    rollingY = (acceleration.y * kFilteringFactor) + (rollingY * (1.0 - kFilteringFactor)); 
    rollingZ = (acceleration.z * kFilteringFactor) + (rollingZ * (1.0 - kFilteringFactor)); 

    // Subtract the low-pass value from the current value to get a simplified high-pass filter 

    float accelX = acceleration.x - rollingX; 
    float accelY = acceleration.y - rollingY; 
    float accelZ = acceleration.z - rollingZ; 

    // Use the acceleration data. 

} 

Answer 2

以防万一有人想知道，高通滤波器可以在Accelerometer Graph sample找到。

Answer 3

这是链接，我也在找这个链接。这是自适应/非自适应高通和低通滤波器的一个例子：Apple iOS Reference Library - AccelerometerGraph Example