BeatRoot Vamp Plugin

class AgentParameters

{

public:

    static const double DEFAULT_POST_MARGIN_FACTOR;

    static const double DEFAULT_PRE_MARGIN_FACTOR;

    static const double DEFAULT_MAX_CHANGE;

    static const double DEFAULT_EXPIRY_TIME;

    AgentParameters() :

        postMarginFactor(DEFAULT_POST_MARGIN_FACTOR),

        preMarginFactor(DEFAULT_PRE_MARGIN_FACTOR),

        maxChange(DEFAULT_MAX_CHANGE),

        expiryTime(DEFAULT_EXPIRY_TIME) { }

    /** The maximum amount by which a beat can be later than the

     *  predicted beat time, expressed as a fraction of the beat

     *  period. */

    double postMarginFactor;

    /** The maximum amount by which a beat can be earlier than the

     *  predicted beat time, expressed as a fraction of the beat

     *  period. */

    double preMarginFactor;

    /** The maximum allowed deviation from the initial tempo,

     * expressed as a fraction of the initial beat period. */

    double maxChange;

    /** The default value of expiryTime, which is the time (in

     *  seconds) after which an Agent that has no Event matching its

     *  beat predictions will be destroyed. */

    double expiryTime;

};

    /** The default value of innerMargin, which is the maximum time

     * 	(in seconds) that a beat can deviate from the predicted beat

     * 	time without a fork occurring. */

    /** The slope of the penalty function for onsets which do not

     * coincide precisely with predicted beat times. */

    static const double CONF_FACTOR;

    /** The reactiveness/inertia balance, i.e. degree of change in the

     *  tempo, is controlled by the correctionFactor variable.  This

     *  constant defines its default value, which currently is not

     *  subsequently changed. The beat period is updated by the

     *  reciprocal of the correctionFactor multiplied by the

     *  difference between the predicted beat time and matching

     *  onset. */

    /** The maximum time (in seconds) that a beat can deviate from the

     *  predicted beat time without a fork occurring (i.e. a 2nd Agent

     *  being created). */

    double innerMargin;

    /** Controls the reactiveness/inertia balance, i.e. degree of

     *  change in the tempo.  The beat period is updated by the

     *  reciprocal of the correctionFactor multiplied by the

     *  difference between the predicted beat time and matching

     *  onset. */

    double correctionFactor;

    /** The time (in seconds) after which an Agent that has no Event

     *  matching its beat predictions will be destroyed. */

    double expiryTime;

    /** For scoring Agents in a (non-existent) real-time version

     * (otherwise not used). */

    double decayFactor;

    /** Sum of salience values of the Events which have been

     *  interpreted as beats by this Agent, weighted by their nearness

     *  to the predicted beat times. */

    /** How long has this agent been the best?  For real-time version;

     * otherwise not used. */

    /** The number of beats found by this Agent, including

     * interpolated beats. */

    /** The current tempo hypothesis of the Agent, expressed as the

     * beat period in seconds. */

    /** The initial tempo hypothesis of the Agent, expressed as the

     * beat period in seconds. */

    /** The maximum allowed deviation from the initial tempo,

     * expressed as a fraction of the initial beat period. */

    double maxChange;

    /** The list of Events (onsets) accepted by this Agent as beats,

     * plus interpolated beats. */

    Agent(AgentParameters params, double ibi) :

	innerMargin(INNER_MARGIN),

	correctionFactor(DEFAULT_CORRECTION_FACTOR),

	expiryTime(params.expiryTime),

	decayFactor(0),

	preMargin(ibi * params.preMarginFactor),

	postMargin(ibi * params.postMarginFactor),

	idNumber(idCounter++),

	tempoScore(0.0),

	phaseScore(0.0),

	topScoreTime(0.0),

	beatCount(0),

	beatInterval(ibi),

	initialBeatInterval(ibi),

	beatTime(-1.0),

        maxChange(params.maxChange) {