Cue

A Cue is a triplet (key, interval, data) represented by a simple Javascript object.

let cue = {
    key: "mykey",
    interval: new Interval(2.2, 4.31),
    data: {...}
};

key

Unique key. Any value or object that may be used as a key with Map. The purpose of cue key is to uniquely identify a cue object within a collection of cue objects.

interval

Defines the validity of the cue in reference to a numerical dimension, typically a timeline. Intervals represent a contiguous segment on the timeline or singular points (see Interval).

data

The data property is an externally defined value or object associated with the cue. Typically, cue properties key and interval are derived from values within the cue data object (see Cue Creation).

Cue Creation

Cues are typically created by wrapping application-defined data objects. These objects often include properties which define object uniqueness, within some application specific namespace. Property names such as id, key and uuid are often used for this purpose. If so, such object identifiers may be used as cue keys.

Additionally, application objects may define timestamps, durations or other numerical values indicating the validity of the object in reference to a timeline. Property names such as ts, start, end and duration are often used for this purpose. If so, cue interval objects may be created from these values.

// application object
let subtitle = {
    id: 1234,
    text: "This is some text",
    start: 24.3,
    end: 28.7
};

// cue from application object
let cue = {
    key: subtitle.id,
    interval: new Interval(subtitle.start, subtitle.end);
    data: subtitle
};