ardftsrc 0.0.4

High-quality audio sample-rate conversion using the ARDFTSRC algorithm.
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130

use crate::RealtimeResampler;
use num_traits::Float;
use realfft::FftNum;

pub struct RodioResampler<S: rodio::Source, T = f64>
where
    T: Float + FftNum,
{
    inner: S,
    resampler: RealtimeResampler<T>,
    stream_input_ended: bool,
}

impl<S: rodio::Source, T: Float + FftNum> RodioResampler<S, T> {
    pub fn new(inner: S, resampler: RealtimeResampler<T>) -> Self {
        Self { inner, resampler, stream_input_ended: false }
    }
}

impl<S: rodio::Source> Iterator for RodioResampler<S, f32>
where
    S::Item: Float + FftNum + Send + 'static,
{
    type Item = S::Item;

    #[inline]
    fn next(&mut self) -> Option<Self::Item> {
        // Check for a new span
        let new_span_after_next = self.inner.current_span_len() == Some(1);

        // If input is none, end the stream, but keep reading until the resampler is drained.
        match self.inner.next() {
            Some(sample) => {
                self.resampler.write_sample(sample);
            }
            None => {
                if !self.stream_input_ended {
                    self.stream_input_ended = true;
                    self.resampler.finalize();
                }
            }
        }

        if new_span_after_next {
            self.resampler.new_span(
                self.inner.sample_rate().get() as usize,
                self.inner.channels().get() as usize,
            );
        }

        self.resampler.read_sample()
    }
}

impl<S: rodio::Source> Iterator for RodioResampler<S, f64>
where
    S::Item: Float + FftNum + Send + 'static,
{
    type Item = S::Item;

    #[inline]
    fn next(&mut self) -> Option<Self::Item> {
        // Check for a new span
        let new_span_after_next = self.inner.current_span_len() == Some(1);

        // If input is none, end the stream, but keep reading until the resampler is drained.
        match self.inner.next() {
            Some(sample) => {
                self.resampler.write_sample(sample as f64);
            }
            None => {
                if !self.stream_input_ended {
                    self.stream_input_ended = true;
                    self.resampler.finalize();
                }
            }
        }

        if new_span_after_next {
            self.resampler.new_span(
                self.inner.sample_rate().get() as usize,
                self.inner.channels().get() as usize,
            );
        }

        self.resampler.read_sample().map(|sample| sample as f32)
    }
}

impl<S: rodio::Source> rodio::Source for RodioResampler<S, f64>
where
    S::Item: Float + FftNum + Send + 'static + Into<f64>,
{
    fn sample_rate(&self) -> std::num::NonZero<u32> {
        std::num::NonZero::new(self.resampler.span_format_out.sample_rate as u32).unwrap()
    }

    fn channels(&self) -> std::num::NonZero<u16> {
        std::num::NonZero::new(self.resampler.span_format_out.channels as u16).unwrap()
    }

    fn total_duration(&self) -> Option<core::time::Duration> {
        self.inner.total_duration()
    }

    fn current_span_len(&self) -> Option<usize> {
        self.resampler.current_span_len()
    }
}

impl<S: rodio::Source> rodio::Source for RodioResampler<S, f32>
where
    S::Item: Float + FftNum + Send + 'static + Into<f32>,
{
    fn sample_rate(&self) -> std::num::NonZero<u32> {
        std::num::NonZero::new(self.resampler.span_format_out.sample_rate as u32).unwrap()
    }

    fn channels(&self) -> std::num::NonZero<u16> {
        std::num::NonZero::new(self.resampler.span_format_out.channels as u16).unwrap()
    }

    fn total_duration(&self) -> Option<core::time::Duration> {
        self.inner.total_duration()
    }

    fn current_span_len(&self) -> Option<usize> {
        self.resampler.current_span_len()
    }
}