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-rw-r--r--tools/mq_editor/README.md7
-rw-r--r--tools/mq_editor/index.html5
-rw-r--r--tools/mq_editor/mq_extract.js94
3 files changed, 92 insertions, 14 deletions
diff --git a/tools/mq_editor/README.md b/tools/mq_editor/README.md
index bde7e54..c1f2732 100644
--- a/tools/mq_editor/README.md
+++ b/tools/mq_editor/README.md
@@ -27,6 +27,7 @@ open tools/mq_editor/index.html
- **Hop Size:** 64–1024 samples (default 256)
- **Threshold:** dB floor for peak detection (default −60 dB)
+- **Prominence:** Min dB height of a peak above its surrounding "valley floor" (default 1.0 dB). Filters out insignificant local maxima.
- **f·Power:** checkbox — weight spectrum by frequency (`f·FFT_Power(f)`) before peak detection, accentuating high-frequency peaks
- **Keep %:** slider to limit how many partials are shown/synthesized
@@ -121,10 +122,10 @@ For a partial at 440 Hz with `spread = 0.02`: `BW ≈ 8.8 Hz`, `r ≈ exp(−πÂ
## Algorithm
1. **STFT:** Overlapping Hann windows, radix-2 FFT
-2. **Peak Detection:** Local maxima above threshold + parabolic interpolation; optional `f·Power(f)` frequency weighting to accentuate high-frequency peaks
-3. **Forward Tracking:** Birth/death/continuation with frequency-dependent tolerance, candidate persistence
+2. **Peak Detection:** Local maxima above threshold + parabolic interpolation. Includes **Prominence Filtering** (rejects peaks not significantly higher than surroundings). Optional `f·Power(f)` weighting.
+3. **Forward Tracking:** Birth/death/continuation with frequency-dependent tolerance. Includes **Predictive Kinematic Tracking** (uses velocity to track rapidly moving partials).
4. **Backward Expansion:** Second pass extends each partial leftward to recover onset frames
-5. **Bezier Fitting:** Cubic curves with control points at t/3 and 2t/3
+5. **Bezier Fitting:** Cubic curves optimized via **Least-Squares** (minimizes error across all points).
## Implementation Status
diff --git a/tools/mq_editor/index.html b/tools/mq_editor/index.html
index c663c69..a2daff5 100644
--- a/tools/mq_editor/index.html
+++ b/tools/mq_editor/index.html
@@ -272,6 +272,9 @@
<label>Threshold (dB):</label>
<input type="number" id="threshold" value="-20" step="any">
+ <label>Prominence (dB):</label>
+ <input type="number" id="prominence" value="1.0" step="0.1" min="0">
+
<label style="margin-left:16px;" title="Weight spectrum by frequency before peak detection (f * FFT_Power(f)), accentuates high-frequency peaks">
<input type="checkbox" id="freqWeight"> f·Power
</label>
@@ -446,6 +449,7 @@
const hopSize = document.getElementById('hopSize');
const threshold = document.getElementById('threshold');
+ const prominence = document.getElementById('prominence');
const freqWeightCb = document.getElementById('freqWeight');
const keepPct = document.getElementById('keepPct');
const keepPctLabel = document.getElementById('keepPctLabel');
@@ -564,6 +568,7 @@
fftSize: fftSize,
hopSize: parseInt(hopSize.value),
threshold: parseFloat(threshold.value),
+ prominence: parseFloat(prominence.value),
freqWeight: freqWeightCb.checked,
sampleRate: audioBuffer.sampleRate
};
diff --git a/tools/mq_editor/mq_extract.js b/tools/mq_editor/mq_extract.js
index c03e869..97fbb00 100644
--- a/tools/mq_editor/mq_extract.js
+++ b/tools/mq_editor/mq_extract.js
@@ -3,14 +3,14 @@
// Extract partials from audio buffer
function extractPartials(params, stftCache) {
- const {fftSize, threshold, sampleRate, freqWeight} = params;
+ const {fftSize, threshold, sampleRate, freqWeight, prominence} = params;
const numFrames = stftCache.getNumFrames();
const frames = [];
for (let i = 0; i < numFrames; ++i) {
const cachedFrame = stftCache.getFrameAtIndex(i);
const squaredAmp = stftCache.getSquaredAmplitude(cachedFrame.time);
- const peaks = detectPeaks(squaredAmp, fftSize, sampleRate, threshold, freqWeight);
+ const peaks = detectPeaks(squaredAmp, fftSize, sampleRate, threshold, freqWeight, prominence);
frames.push({time: cachedFrame.time, peaks});
}
@@ -30,7 +30,7 @@ function extractPartials(params, stftCache) {
// Detect spectral peaks via local maxima + parabolic interpolation
// squaredAmp: pre-computed re*re+im*im per bin
// freqWeight: if true, weight by f before peak detection (f * Power(f))
-function detectPeaks(squaredAmp, fftSize, sampleRate, thresholdDB, freqWeight) {
+function detectPeaks(squaredAmp, fftSize, sampleRate, thresholdDB, freqWeight, prominenceDB = 0) {
const mag = new Float32Array(fftSize / 2);
const binHz = sampleRate / fftSize;
for (let i = 0; i < fftSize / 2; ++i) {
@@ -44,6 +44,24 @@ function detectPeaks(squaredAmp, fftSize, sampleRate, thresholdDB, freqWeight) {
mag[i] > mag[i-1] && mag[i] > mag[i-2] &&
mag[i] > mag[i+1] && mag[i] > mag[i+2]) {
+ // Check prominence if requested
+ if (prominenceDB > 0) {
+ let minLeft = mag[i];
+ for (let k = i - 1; k >= 0; --k) {
+ if (mag[k] > mag[i]) break; // Found higher peak
+ if (mag[k] < minLeft) minLeft = mag[k];
+ }
+
+ let minRight = mag[i];
+ for (let k = i + 1; k < mag.length; ++k) {
+ if (mag[k] > mag[i]) break; // Found higher peak
+ if (mag[k] < minRight) minRight = mag[k];
+ }
+
+ const valley = Math.max(minLeft, minRight);
+ if (mag[i] - valley < prominenceDB) continue;
+ }
+
// Parabolic interpolation for sub-bin accuracy
const alpha = mag[i-1];
const beta = mag[i];
@@ -77,12 +95,15 @@ function trackPartials(frames) {
// Continue active partials
for (const partial of activePartials) {
const lastFreq = partial.freqs[partial.freqs.length - 1];
+ const velocity = partial.velocity || 0;
+ const predicted = lastFreq + velocity;
+
const tol = Math.max(lastFreq * trackingRatio, minTrackingHz);
let bestIdx = -1, bestDist = Infinity;
for (let i = 0; i < frame.peaks.length; ++i) {
if (matched.has(i)) continue;
- const dist = Math.abs(frame.peaks[i].freq - lastFreq);
+ const dist = Math.abs(frame.peaks[i].freq - predicted);
if (dist < tol && dist < bestDist) { bestDist = dist; bestIdx = i; }
}
@@ -92,6 +113,7 @@ function trackPartials(frames) {
partial.freqs.push(pk.freq);
partial.amps.push(pk.amp);
partial.age = 0;
+ partial.velocity = pk.freq - lastFreq;
matched.add(bestIdx);
} else {
partial.age++;
@@ -102,12 +124,15 @@ function trackPartials(frames) {
for (let i = candidates.length - 1; i >= 0; --i) {
const cand = candidates[i];
const lastFreq = cand.freqs[cand.freqs.length - 1];
+ const velocity = cand.velocity || 0;
+ const predicted = lastFreq + velocity;
+
const tol = Math.max(lastFreq * trackingRatio, minTrackingHz);
let bestIdx = -1, bestDist = Infinity;
for (let j = 0; j < frame.peaks.length; ++j) {
if (matched.has(j)) continue;
- const dist = Math.abs(frame.peaks[j].freq - lastFreq);
+ const dist = Math.abs(frame.peaks[j].freq - predicted);
if (dist < tol && dist < bestDist) { bestDist = dist; bestIdx = j; }
}
@@ -116,6 +141,7 @@ function trackPartials(frames) {
cand.times.push(frame.time);
cand.freqs.push(pk.freq);
cand.amps.push(pk.amp);
+ cand.velocity = pk.freq - lastFreq;
matched.add(bestIdx);
if (cand.times.length >= birthPersistence) {
activePartials.push(cand);
@@ -130,7 +156,13 @@ function trackPartials(frames) {
for (let i = 0; i < frame.peaks.length; ++i) {
if (matched.has(i)) continue;
const pk = frame.peaks[i];
- candidates.push({times: [frame.time], freqs: [pk.freq], amps: [pk.amp], age: 0});
+ candidates.push({
+ times: [frame.time],
+ freqs: [pk.freq],
+ amps: [pk.amp],
+ age: 0,
+ velocity: 0
+ });
}
// Kill aged-out partials
@@ -251,19 +283,59 @@ function autodetectSpread(partial, stftCache, fftSize, sampleRate) {
return {spread_above, spread_below};
}
-// Fit cubic bezier to trajectory using samples at ~1/3 and ~2/3 as control points
+// Fit cubic bezier to trajectory using least-squares for inner control points
function fitBezier(times, values) {
const n = times.length - 1;
const t0 = times[0], v0 = values[0];
const t3 = times[n], v3 = values[n];
const dt = t3 - t0;
- if (dt <= 0 || n === 0) {
- return {t0, v0, t1: t0, v1: v0, t2: t3, v2: v3, t3, v3};
+ if (dt <= 1e-9 || n < 2) {
+ // Linear fallback for too few points or zero duration
+ return {t0, v0, t1: t0 + dt / 3, v1: v0 + (v3 - v0) / 3, t2: t0 + 2 * dt / 3, v2: v0 + 2 * (v3 - v0) / 3, t3, v3};
}
- const v1 = values[Math.round(n / 3)];
- const v2 = values[Math.round(2 * n / 3)];
+ // Least squares solve for v1, v2
+ // Bezier: B(u) = (1-u)^3*v0 + 3(1-u)^2*u*v1 + 3(1-u)*u^2*v2 + u^3*v3
+ // Target_i = val_i - (1-u)^3*v0 - u^3*v3
+ // Model_i = A_i*v1 + B_i*v2
+ // A_i = 3(1-u)^2*u
+ // B_i = 3(1-u)*u^2
+
+ let sA2 = 0, sB2 = 0, sAB = 0, sAT = 0, sBT = 0;
+
+ for (let i = 0; i <= n; ++i) {
+ const u = (times[i] - t0) / dt;
+ const u2 = u * u;
+ const u3 = u2 * u;
+ const invU = 1.0 - u;
+ const invU2 = invU * invU;
+ const invU3 = invU2 * invU;
+
+ const A = 3 * invU2 * u;
+ const B = 3 * invU * u2;
+ const target = values[i] - (invU3 * v0 + u3 * v3);
+
+ sA2 += A * A;
+ sB2 += B * B;
+ sAB += A * B;
+ sAT += A * target;
+ sBT += B * target;
+ }
+
+ const det = sA2 * sB2 - sAB * sAB;
+ let v1, v2;
+
+ if (Math.abs(det) < 1e-9) {
+ // Fallback to simple 1/3, 2/3 heuristic if matrix is singular
+ const idx1 = Math.round(n / 3);
+ const idx2 = Math.round(2 * n / 3);
+ v1 = values[idx1];
+ v2 = values[idx2];
+ } else {
+ v1 = (sB2 * sAT - sAB * sBT) / det;
+ v2 = (sA2 * sBT - sAB * sAT) / det;
+ }
return {t0, v0, t1: t0 + dt / 3, v1, t2: t0 + 2 * dt / 3, v2, t3, v3};
}
generated by cgit v1.2.3 (git 2.51.0) at 2026-02-18 21:05:33 +0000