这是一个对语音信号(0.3kHz~3.4kHz)进行低通滤波的C语言程序。低通滤波的截止频率为800Hz，滤波器采用19点的有限冲击响应FIR滤波。-This is a speech signal (0.3 kHz to 3.4 kHz) to low pass filtering of C language program. Low pass filter cutoff frequency for 800 Hz, filter adopting the shock response limit