32 lines
710 B
Nim
32 lines
710 B
Nim
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import math
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const TwoPi = PI * 2
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type
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ParamSmooth* = object
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a, b, t, z: float
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fs: float64
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proc reset*(self: var ParamSmooth) =
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self.z = 0.0
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proc setSampleRate*(self: var ParamSmooth, sampleRate: float64) =
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if sampleRate != self.fs:
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self.fs = sampleRate
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self.a = exp(-TwoPi / (self.t * 0.001 * sampleRate))
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self.b = 1.0 - self.a
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self.z = 0.0
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proc process*(self: var ParamSmooth, sample: float): float =
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self.z = (sample * self.b) + (self.z * self.a)
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return self.z
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proc initParamSmooth*(smoothingTimeMs: float = 20.0, sampleRate: float64 = 48_000.0): ParamSmooth =
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result.t = smoothingTimeMs
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result.setSampleRate(sampleRate)
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