1 files changed, 24 insertions, 12 deletions
diff --git a/tools/mq_editor/app.js b/tools/mq_editor/app.js
index 20224a0..9857c64 100644
--- a/tools/mq_editor/app.js
+++ b/tools/mq_editor/app.js
@@ -481,6 +481,25 @@ function getSynthParams() {
   };
 }
 
+// Synthesize partials and return an AudioBuffer, trimmed to [t_start-margin, t_end+margin]
+function getAudioBuffer(partials, margin = 0) {
+  const sr = audioBuffer.sampleRate;
+  const {integratePhase, opts} = getSynthParams();
+  const pcm = synthesizeMQ(partials, sr, audioBuffer.duration, integratePhase, opts);
+  let startSample = 0, endSample = pcm.length;
+  if (margin >= 0 && partials.length > 0) {
+    const times = partials.flatMap(p => p.times);
+    const tStart = Math.min(...times);
+    const tEnd   = Math.max(...times);
+    startSample = Math.max(0, Math.floor((tStart - margin) * sr));
+    endSample   = Math.min(pcm.length, Math.ceil((tEnd + margin) * sr));
+  }
+  const trimmed = pcm.subarray(startSample, endSample);
+  const buf = audioContext.createBuffer(1, trimmed.length, sr);
+  buf.getChannelData(0).set(trimmed);
+  return buf;
+}
+
 // Play synthesized audio
 function playSynthesized() {
   if (!extractedPartials || extractedPartials.length === 0) {
@@ -497,16 +516,14 @@ function playSynthesized() {
   const partialsToUse = extractedPartials.slice(0, keepCount).filter(p => !p.muted);
   setStatus(`Synthesizing ${partialsToUse.length}/${extractedPartials.length} partials (${keepPct.value}%)...`, 'info');
 
-  const {integratePhase, opts} = getSynthParams();
-  const pcm = synthesizeMQ(partialsToUse, audioBuffer.sampleRate, audioBuffer.duration,
-                           integratePhase, opts);
-
   if (viewer) {
+    const {integratePhase, opts} = getSynthParams();
+    const pcm = synthesizeMQ(partialsToUse, audioBuffer.sampleRate, audioBuffer.duration,
+                             integratePhase, opts);
     viewer.setSynthStftCache(new STFTCache(pcm, audioBuffer.sampleRate, fftSize, parseInt(hopSize.value)));
   }
 
-  const synthBuffer = audioContext.createBuffer(1, pcm.length, audioBuffer.sampleRate);
-  synthBuffer.getChannelData(0).set(pcm);
+  const synthBuffer = getAudioBuffer(partialsToUse);
   playAudioBuffer(synthBuffer, `Playing synthesized (${partialsToUse.length}/${extractedPartials.length} partials, ${keepPct.value}%)...`);
 }
 
@@ -535,12 +552,7 @@ document.addEventListener('keydown', (e) => {
     const partial = extractedPartials[sel];
     if (!partial) return;
     stopAudio();
-    const {integratePhase, opts} = getSynthParams();
-    const pcm = synthesizeMQ([partial], audioBuffer.sampleRate, audioBuffer.duration,
-                             integratePhase, opts);
-    const buf = audioContext.createBuffer(1, pcm.length, audioBuffer.sampleRate);
-    buf.getChannelData(0).set(pcm);
-    playAudioBuffer(buf, `Playing partial #${sel}...`);
+    playAudioBuffer(getAudioBuffer([partial], 0.05), `Playing partial #${sel}...`);
   } else if (e.code === 'KeyP') {
     e.preventDefault();
     if (viewer) viewer.togglePeaks();