Initial Commit

packages/media/audio/audio-analysis-pitch/tests/helpers.ts

@@ -0,0 +1,63 @@
+import { AudioDocument } from "@suaveplan/audio-core";
+
+export function buildSineDoc(
+    freq: number,
+    sampleRate: number,
+    durationSamples: number,
+    channels = 1
+): AudioDocument {
+    const data: Float32Array[] = [];
+    for (let c = 0; c < channels; c++) {
+        const arr = new Float32Array(durationSamples);
+        for (let i = 0; i < durationSamples; i++) {
+            arr[i] = Math.sin((2 * Math.PI * freq * i) / sampleRate);
+        }
+        data.push(arr);
+    }
+    const doc = new AudioDocument({
+        sampleRate,
+        channels,
+        sourceLength: 0,
+    });
+    doc.push(data);
+    return doc;
+}
+
+export function buildSilentDoc(
+    sampleRate: number,
+    durationSamples: number,
+    channels = 1
+): AudioDocument {
+    const data: Float32Array[] = [];
+    for (let c = 0; c < channels; c++) {
+        data.push(new Float32Array(durationSamples));
+    }
+    const doc = new AudioDocument({
+        sampleRate,
+        channels,
+        sourceLength: 0,
+    });
+    doc.push(data);
+    return doc;
+}
+
+export function buildChordDoc(
+    pitches: number[],
+    sampleRate: number,
+    durationSamples: number
+): AudioDocument {
+    const arr = new Float32Array(durationSamples);
+    for (let i = 0; i < durationSamples; i++) {
+        let s = 0;
+        for (const f of pitches)
+            s += Math.sin((2 * Math.PI * f * i) / sampleRate);
+        arr[i] = s / pitches.length;
+    }
+    const doc = new AudioDocument({
+        sampleRate,
+        channels: 1,
+        sourceLength: 0,
+    });
+    doc.push([arr]);
+    return doc;
+}