Abstract: An interactive multimedia presentation has a predetermined presentation play duration, a video content component (which may include video, audio, data, or any combination thereof), and an interactive content component. Methods and systems for playing the presentation include specifying a time when a particular media object is renderable. The time is specifiable using an application instruction that references either a first timing signal having a rate that is based on the play speed of the presentation, or a second timing signal having a continuous rate. One example of an application instruction usable as described above is an element associated with an XML data structure. An attribute of the element, such as the clock attribute, may be used to provide time values for the element that reference either timing signal. The attribute is used to maintain frame-accurate synchronization between the video and the interactive content components of the presentation.

Abstract: Using declarative language application instructions, actions associated with playing interactive content of an interactive multimedia presentation are triggered based on a state change of a particular media object. Certain application instructions specify the characteristic of the media object, while other application instructions specify the actions associated with playing the interactive content (for example, when media objects are renderable, event generation, script execution, or changes in variables) based on a state change of the characteristic. The state change is detected by querying a structured representation of the application such as a document object model, which includes nodes associated with the application instructions, the media object, and/or the characteristic. When state changes are detected, one or more of the specified actions are triggered to thereby declaratively respond to the state change.

Abstract: An interactive multimedia presentation has an interactive content component that includes an application, which has instructions for rendering a media object. By nesting a declarative language event instruction inside of a declarative language timing instruction, a particular event can arise and/or be handled (for example, a media object is rendered) only within a time interval specified by the timing instruction. The event instruction specifies when a particular event (such as a user event, a system event, a document object event, or another type of event) arises. When the event arises during the time interval, the event may be handled. Outside of the time interval, even if the event arises, the event is not handled. In this manner, responses to the event are constrained to happen in the time interval, and events that are not handled within a certain time may be ignored.

Abstract: Using declarative language application instructions, one or more actions associated with playing interactive content of an interactive multimedia presentation are conditionally triggered based on a state change of a style or non-style characteristic of a particular media object. Certain application instructions specify the characteristic of the media object, while other application instructions specify the actions associated with playing the interactive content (for example, when one or more media objects are renderable, event generation, script execution, or changes in variables) based on a state change of the characteristic. The state change is detected by querying a structured representation of the application, which includes nodes associated with the application instructions, the media object, and/or the characteristic. When state changes are detected, one or more of the specified actions are triggered.