嵌入式音频架构 - AudioWeaver模块库 Filter 滤波器
Filter
ADAPTIVE (LMS) 自适应滤波器:
FILTERS WITH CALCULATED COEFFS
ALLPASS PAIR: 创建一对allpass filter, 他们输出的和以及差形成一对高通和低通滤波器。
audio weighting filter:加权重的滤波器。加的权重符合ITU468, LeqM, and ITU 1770标准中的A计权, B计权,C计权,D计权。
Cossover Filter: 这是一种特殊的滤波器,可以将信号分为不同的频带,但是保持整体信号强度不变。一般采用butterworth Filter 奇数阶数或者Linkwtiz-
Riley Filter偶数阶数。也可以使用串联 lane filter 和 allpass filter。
Emphasis Filter:有 pre-emphasis 和 de-emphasis两种。
Graphic EQs: 将信号分为几个频带,可以衰减或者增强。频带是按对数分布在频域上。每个频带的gain值都可以设置。
Hilbert:将信号在全频带偏移相位 -n/2 radians。
Pink Filter: 每倍频程衰减3dB的lowpass filter 。
THREE BAND TONE CONTROL: 3个频带的带通滤波器
CONTROLLABLE FILTERS: 滤波器参数可以被外部实时控制。频率,Q,gain。
FIRST ORDER FILTER CONTROL: 截止频率可以控制。
LPF CONTROL:一阶low pass filter,频率可控制。
SECOND ORDER FILTER CONTROL:频率,gain,Q值可控制。参数update时间可降低频率,来节省MIPS。
FILTERS WITH RAW COEFFS:参数可导入的滤波器,可选择FIR 或 IIR。
HIGH PRECISION FILTERS: 直接II型IIR. 这个模块是DSP concept IP的滤波器,可以减少截断误差。
BUTTERWORTHFILTER:
SECONDORDERFILTERSMOOTHED: 2阶IIR,可以设计成20种不同的滤波器,频率,gain,Q值可调。
Pass Through | |
Gain | |
1st order Butterworth lowpass filter | |
2nd order Butterworth lowpass | |
1st order Butterworth highpass | |
2nd order Butterworth highpass | |
1st order allpass | |
2nd order allpass | |
2nd order low shelf | |
2nd order low shelf with Q | |
2nd order high shelf | |
2nd order high shelf with Q | |
2nd order peaking / parametric | |
2nd order notch | |
2nd order bandpass filter | |
1st order Bessel lowpass filter | |
1st order Bessel highpass filter | |
1st order asymmetrical low shelf | |
1st order asymmetrical high shelf | |
1st order symmetrical low shelf | |
1st order symmetrical high shelf | |