中文说明：
半带滤波器是另一种计算效率高、实时性强的高效滤波器。这种滤波器特别适合作变换因子为2N倍的抽取或内插运算。
English Description：
Half band filter is another efficient filter with high computational efficiency and strong real-time performance. This filter is especially suitable for decimation or interpolation with a transformation factor of 2n times