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Add subtle white noise sound effect during TV static
Uses Web Audio API to generate looped white noise at low volume
during channel switches, with a quick fade-out to avoid clicks.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
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public/index.html
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public/index.html
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let staticCtx = staticCanvas.getContext('2d');
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let staticAnimFrame = null;
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// --- Static TV audio (white noise via Web Audio API) ---
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let staticAudioCtx = null;
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let staticNoiseNode = null;
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let staticGainNode = null;
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function startStaticAudio() {
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try {
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if (!staticAudioCtx) {
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staticAudioCtx = new (window.AudioContext || window.webkitAudioContext)();
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}
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if (staticAudioCtx.state === 'suspended') staticAudioCtx.resume();
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if (staticNoiseNode) return; // already playing
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// Create white noise buffer (1 second, looped)
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const bufferSize = staticAudioCtx.sampleRate;
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const noiseBuffer = staticAudioCtx.createBuffer(1, bufferSize, staticAudioCtx.sampleRate);
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const data = noiseBuffer.getChannelData(0);
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for (let i = 0; i < bufferSize; i++) {
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data[i] = Math.random() * 2 - 1;
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}
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staticNoiseNode = staticAudioCtx.createBufferSource();
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staticNoiseNode.buffer = noiseBuffer;
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staticNoiseNode.loop = true;
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staticGainNode = staticAudioCtx.createGain();
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staticGainNode.gain.value = 0.015; // barely there
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staticNoiseNode.connect(staticGainNode);
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staticGainNode.connect(staticAudioCtx.destination);
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staticNoiseNode.start();
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} catch (e) {
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// Audio context not available — fine, just skip
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}
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}
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function stopStaticAudio() {
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if (staticNoiseNode) {
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try {
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// Quick fade out to avoid click
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if (staticGainNode) {
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staticGainNode.gain.setTargetAtTime(0, staticAudioCtx.currentTime, 0.02);
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}
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setTimeout(() => {
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try { staticNoiseNode.stop(); } catch (e) {}
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staticNoiseNode = null;
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staticGainNode = null;
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}, 80);
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} catch (e) {
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staticNoiseNode = null;
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staticGainNode = null;
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}
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}
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}
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async function fetchVods() {
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let all = [];
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let cursor;
···
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function startStatic() {
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staticOverlay.classList.add('active');
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if (!staticAnimFrame) drawStatic();
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startStaticAudio();
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}
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function stopStatic() {
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staticOverlay.classList.remove('active');
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if (staticAnimFrame) { cancelAnimationFrame(staticAnimFrame); staticAnimFrame = null; }
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stopStaticAudio();
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}
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function showChannelInfo(ch, title, uri) {