Add beat detection Rust POC

libpulse_aubio/src/main.rs

@@ -0,0 +1,56 @@
+use anyhow::Result;
+use psimple::Simple;
+use pulse::sample::{Format, Spec};
+use pulse::stream::Direction;
+
+const BUF_SIZE: usize = 1024;
+const HOP_SIZE: usize = 512;
+const SAMPLE_RATE: u32 = 44100;
+
+fn main() -> Result<()> {
+    let spec = Spec {
+        format: Format::F32le,
+        channels: 2,
+        rate: 44100,
+    };
+    assert!(spec.is_valid());
+
+    let s = Simple::new(
+        None,
+        "AAAAAAAA",
+        Direction::Record,
+        None,
+        "BBBBBBBB",
+        &spec,
+        None,
+        None,
+    )?;
+
+    let mut tempo = aubio::Tempo::new(aubio::OnsetMode::SpecFlux, BUF_SIZE, HOP_SIZE, SAMPLE_RATE)?;
+
+    let mut data = [0u8; 4 * BUF_SIZE];
+    let mut float_data = [0f32; BUF_SIZE];
+
+    loop {
+        s.read(&mut data)?;
+
+        for (i, f) in float_data.iter_mut().enumerate() {
+            let mut float_bytes = [0u8; 4];
+            float_bytes.copy_from_slice(&data[4 * i..4 * i + 4]);
+            *f = f32::from_le_bytes(float_bytes);
+        }
+
+        let r = tempo.do_result(&float_data)?;
+
+        if r > 0f32 {
+            println!(
+                "{}ms, {}s, frame {}, {} bpm, confidence {}",
+                tempo.get_last_ms(),
+                tempo.get_last_s(),
+                tempo.get_last(),
+                tempo.get_bpm(),
+                tempo.get_confidence()
+            );
+        }
+    }
+}