rawdio 0.14.0

An Audio Engine, inspired by the Web Audio API
Documentation 
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use std::time::Duration;

use itertools::izip;
use rawdio::{prelude::*, Recorder};

fn record_sampler(
    sample_rate: usize,
    channel_count: usize,
    buffer: &OwnedAudioBuffer,
) -> OwnedAudioBuffer {
    let (mut context, mut process) =
        create_engine_with_options(EngineOptions::default().with_sample_rate(sample_rate));

    let recorder = Recorder::new(context.as_mut(), channel_count, sample_rate);

    connect_nodes!("input" => recorder.borrow_mut());

    recorder.borrow_mut().record_now();
    recorder
        .borrow_mut()
        .stop_record_at_time(Timestamp::from_samples(
            (buffer.frame_count() + 1) as f64,
            sample_rate,
        ));

    let frame_count = 2 * buffer.frame_count();

    let mut input_buffer = OwnedAudioBuffer::new(frame_count, channel_count, sample_rate);

    input_buffer.copy_from(
        buffer,
        SampleLocation::origin(),
        SampleLocation::origin(),
        channel_count,
        buffer.frame_count(),
    );

    let mut output_buffer = OwnedAudioBuffer::new(frame_count, channel_count, sample_rate);

    context.start();
    process.process(&input_buffer, &mut output_buffer);

    context.process_notifications();

    context.stop();

    let recording = recorder
        .borrow_mut()
        .take_recording()
        .expect("No recording was made");

    recording
}

fn has_identical_data(buffer_1: &dyn AudioBuffer, buffer_2: &dyn AudioBuffer) -> bool {
    if buffer_1.channel_count() != buffer_2.channel_count() {
        return false;
    }

    if buffer_1.frame_count() != buffer_2.frame_count() {
        return false;
    }

    for channel in 0..buffer_1.channel_count() {
        let location = SampleLocation::channel(channel);
        let buffer_1_data = buffer_1.get_channel_data(location);
        let buffer_2_data = buffer_2.get_channel_data(location);

        if izip!(buffer_1_data.iter(), buffer_2_data.iter())
            .any(|(buffer_1_sample, buffer_2_sample)| buffer_1_sample != buffer_2_sample)
        {
            return false;
        }
    }

    true
}

#[test]
fn records_data() {
    let sample_duration = Duration::from_secs(1);
    let sample_rate = 48_000;

    let sample_duration = Timestamp::from_duration(sample_duration);
    let sample_frame_count = sample_duration.as_samples(sample_rate).ceil() as usize;

    let channel_count = 2;

    let buffer = OwnedAudioBuffer::white_noise(sample_frame_count, channel_count, sample_rate);
    let recorded_buffer = record_sampler(sample_rate, channel_count, &buffer);

    for channel in 0..channel_count {
        assert!(!recorded_buffer.channel_is_silent(channel));
    }

    assert!(has_identical_data(&buffer, &recorded_buffer));
}