FIR滤波器的C语言实现

下面代码实现的是一个四阶的FIR滤波器：

#define FILTER_LEN 5
float h[FILTER_LEN] = {0.0625,0.25,0.375,0.25,0.0625};
float fDelayLine[FILTER_LEN] = {0,0,0,0,0};
void FIR_Filter(void)
{int i;float ftemp;ftemp = 0;for(i = FILTER_LEN-1;i > 0;i--){fDelayLine[i] = fDelayLine[i-1];ftemp += h[i]*fDelayLine[i];}fDelayLine[0] = (float)xAdcInput;ftemp += fDelayLine[0]*fDelayLine[0];xResult = ftemp;
}