Loudness and Confidence filter

gistfile1.js

function runLength(quanta, confidenceThreshold, loudnessThreshold, lookAhead, lookaheadMatch) {
    var lastState = false;

    for (var i = 0; i < quanta.length; i++) {
        quanta[i].needsDrums = false;
    }

    for (var i = 0; i < quanta.length -1; i+=2) {
        var newState = getState(quanta[i], confidenceThreshold, loudnessThreshold);
        if (newState != lastState) {
            // look ahead
            var matchCount = 0
            var curCount = 0;
            for (var j = i + 1; j < quanta.length && j <= i + lookAhead; j++) {
                var q = quanta[j];
                var nstate = getState(q, confidenceThreshold, loudnessThreshold);

                if (nstate == newState) {
                    matchCount++;
                }
                curCount++;
            }
            if (matchCount > lookaheadMatch) {
                curState = newState;
            } else {
                curState = lastState;
            }
        } else {
            curState = newState;
        }
        quanta[i].needsDrums = curState;
        quanta[i+1].needsDrums = curState;
        lastState = curState;
    }
}

function getState(q, confidenceThreshold, loudnessThreshold) {
    var conf = q.confidence;
    var volume = q.oseg.loudness_max;
    var nstate = conf >= confidenceThreshold && volume > loudnessThreshold;
    return nstate;
}