40 lines
776 B
Rust
40 lines
776 B
Rust
use crate::fm_demod::Sample;
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pub struct LowPass<I> {
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inner: I,
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y_prev: Sample,
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alpha: f32,
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}
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impl<I> LowPass<I> {
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pub fn new(inner: I, alpha: f32) -> Self {
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Self {
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inner,
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y_prev: 0.0,
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alpha,
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}
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}
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pub fn process_sample(&mut self, x_n: Sample) -> Sample {
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let y_n = self.alpha * x_n + (1.0 - self.alpha) * self.y_prev;
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self.y_prev = y_n;
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y_n
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}
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}
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impl<I, E> Iterator for LowPass<I>
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where
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I: Iterator<Item = Result<Sample, E>>,
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{
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type Item = Result<Sample, E>;
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fn next(&mut self) -> Option<Self::Item> {
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match self.inner.next()? {
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Ok(sample) => Some(Ok(self.process_sample(sample))),
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Err(e) => Some(Err(e)),
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}
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}
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}
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