数字滤波函数，实现数字信号的读入，利用MMX指令集实现信号的快速处理-digital filter function, digital signal read, the use of MMX instruction set to achieve the rapid signal processing

中值滤波算法，利用intel的mmx技术，速度比普通快上几十倍-median filter, using the MMX technique from Intel, the speed is quite promising when compared to normal one