Detect audio playback in video element

gistfile1.txt

// Use WebAudio API to detect audio playback with volume
// Returns early with false when audio could not be playing
// Returns null if WebAudio API cannot be used while media is in a playing state
function isMediaPlayingAudio(mediaElement) {
    if (media.paused || media.muted || media.volume === 0 || media.played.length < 1) {
        return false;
    }
    let analyser = media.audioAnalyser;
    let audioCtx = media.audioCtx;
    if (!analyser) {
        if (!window.AudioContext) {
            return null;
        }
        try {
            audioCtx = new window.AudioContext();
            const source = audioCtx.createMediaElementSource(media);
            analyser = audioCtx.createAnalyser();
            analyser.fftSize = 256;
            source.connect(analyser).connect(audioCtx.destination);
            media.audioAnalyser = analyser;
            media.audioCtx = audioCtx;
        } catch (error) {
            console.warn('Could not analyze audio', error);
            return null;
        }
    }
    const data = new Uint8Array(analyser.frequencyBinCount);
    analyser.getByteTimeDomainData(data);
    return data.some(int => int !== 128);
}