The primary use of navigational links in a DVD is to define a default organization and path through the disc. Typically, when you design a DVD, you create a hierarchy of menus, spread down from the main menu, to organize and access the content of the disc.
There are two different approaches to organizing and presenting your material on a DVD:
Editing your material together as a single movie timeline allows it to play smoothly from the beginning to the end (because this is the whole idea of movies on DVD). You also can jump into the timeline at any chapter point, but then must play to the end; Encore does not provide the ability to play only a partial sequence from the middle of a longer timeline.
Organizing your material as a group of separate clips provides the ability to play each clip independently. In addition, you can link them together into a sequence by setting the End Action links for the timelines to chain from one to the next. However, there is no guarantee that every DVD player can play through these links seamlessly. Instead, you should plan for the possibility that there will be a short hesitation between clips, and therefore fade the audio and fade or freeze the video, if needed, through the discontinuity.
Many DVDs contain a main movie, or a single long piece of content, that has been edited into one continuous clip. A menu hierarchy for this kind of movie disc is shown in Figure 7-1, with buttons for the main movie and a scene index menu to access chapter points in the movie.
To create this kind of movie DVD, you import the movie clip into a timeline, mark chapter points, and add any alternate audio or subtitle tracks. To view this main content, the main menu typically contains a Play Movie button to play the entire main content of the disc (the main timeline), plus a Scene Index button to access a linked series of menus to jump to individual scenes within the movie (chapter points in the timeline). This type of DVD can also use a Setup button to access a menu to select alternate audio or subtitle tracks (by explicitly specifying the tracks along with the link).
When jumping into a movie from a scene/chapter index menu, playback starts by jumping to a chapter point in the longer movie clip, and then continues from there all the way to the end of the movie, passing any other chapter points along the way (see Figure 7-2).
Other DVDs contain a collection of individual clips that the user may want to view individually, or just watch some or all of them together. A menu hierarchy for this kind of movie disc is shown in Figure 7-3, with a clip index menu to access the individual clips, plus other options to play through groups of clips.
To create this kind of clip-based DVD, you import a collection of short clips and create individual timelines for each. The timelines typically do not need to have chapter points defined because the clips are shorter and you are accessing the disc’s contents by clips and not chapters. To view the clips, the main menu typically contains a button to link to a sequence of clip index menus. These are much like the scene/chapter index menus in a movie disc, except that each clip is played individually.
When jumping into a movie from a clip index menu, playback starts by jumping to the beginning of the clip, continues from to the end of the individual clip, and then returns to the menu without playing any other clips (see Figure 7-4).
In both cases, the menu button links into a timeline, and playback continues to the end of that timeline. The real difference is in the organization of the material on the disc: either as one long continuous timeline with chapter points, or as a collection of clips, each in a separate timeline that can be played individually or linked together into a sequence.
Note
You can override any link within the DVD navigation: menu and timeline end actions, menu buttons, and even the first play. The only links without overrides are for the Title and Menu buttons on the DVD remote control.
While this discussion focuses on using overrides with timelines to reuse clips, it applies to menus as well. For example, you can create alternate versions of self-running DVDs (with menus that timeout), or reuse a sequence of menus originally used for a slide show.
As you know, to link timelines in Encore you specify the End Action link in the Properties palette for the timeline. For example, a typical end action might be to return to the menu that links to it, or it might be to link to another timeline, chaining multiple timelines into a longer sequence.
But what if you need to do both to provide multiple options for viewing the content on your disc? After all, the whole purpose of organizing clips into separate timelines is to permit the same material to be accessed and played in different ways, so you can reuse the clips instead of having to fill up the disc with additional timelines with copies of the same clips. This is the reason for Override links.
The idea behind associating an override with a link is that you not only want to specify what plays next, but also want to control what happens after that linked element finishes playing. In this way, you can define the default behavior for the typical use of the material on the disc, and also reuse the material in different ways. We touched on overrides briefly in Chapter 4 and Chapter 5, but let’s look at how we can use them to our advantage here.
One simple example might be a disc that has a number of clips on it documenting a soccer season. Each clip is accessed from a clip index, in which the menu button link is set to link to the clip timeline, and the End Action of the timeline is set to link back to the menu that accesses it (see Figure 7-5).
Note
Encore provides two handy links for this common case of specifying the navigational flow from menus to timelines and back again. Instead of having to explicitly set a menu name as the link target, you can use the general links Link Back to Here and Return to Last Menu that are provided in the pop-out link menu.
When specifying an Override link from a menu button to a timeline, just set the link to Link Back to Here, and the timeline will return to the same menu that linked to it.
When specifying the End Action for a timeline, set the link to Return to Last Menu, and playback will then link back to the last menu that was viewed.
These general links have several huge advantages: you don’t need to explicitly specify the menu for each link, and the timeline end action is not locked to a specific menu, so the timeline automatically can be linked from any menu. In addition, as you will see next, you can use the Project window to easily check these settings, and even set the links for multiple menus and timelines at once.
However, it might also be useful to provide an alternate clip index menu, which presents commentary from the coach, followed by a third menu that provides commentary from the players. To do this, you can create a button on the Coach’s Commentary menu with its link set to the same timeline, but also with an override set to the Player Commentary. This will then override the default end action defined for the timeline, and cause playback to jump to the third menu (see Figure 7-6).
Here’s another idea: you could also reuse this clip as the First Play link for the disc, with an override set to link to the main menu when the clip finishes playing. In this case, we’ll only play the final few seconds of the clip by jumping directly to the final chapter, Chapter 5, in the timeline. Figure 7-7 shows how to do this.
Although overrides are useful for reusing individual clips, they cannot be used to create links to sequences of multiple clips. The override for a link overrides only the end action of the next played element, not a sequence of elements.
Note
You also can create a new playlist from a group of timelines. First, select one or more timelines in the Project window (again, that’s timelines and not just clips). Then click Create Playlist to create a new playlist that already includes the selected timelines. You then can drag to reorder the list, or explicitly add other elements with chapter points.
Thankfully, Encore added the playlist in version 1.5 as the mechanism to define lists of timelines to be played in a sequence. A playlist acts much like a timeline in Encore, in that any other element can link to it. The playlist will play through all the timelines that it contains, and then execute the end action. This is useful, for example, if you want to provide a way to play through an entire list of deleted scenes, without returning to a menu after each one.
To create a new playlist, click the Create a New Playlist button at the bottom of the Project tab, or choose File → New Playlist. Encore creates a new empty Playlist element, listed in the Project tab. To edit the playlist, select it in the Project tab and display the playlist Properties palette (see Figure 7-8).
You can use the Playlist Inspector in the Properties palette to build the list of timelines to be played:
You can add a timeline to the playlist by using the flyout links menu, or dragging from the pick whip to a timeline (or chapter point) in the Project or Timelines tab. Use Specify Other from the flyout menu to specify the audio and subtitle tracks associated with a link.
You can select multiple elements by using Shift-click.
You can reorder elements in the playlist by dragging them up or down.
Finally, you can delete elements from the playlist by selecting them and clicking the Trash icon on the lower right side of the palette, or by choosing Delete from the palette menu.