Objectives. (Sue Stinson)

Transcription

1 23 Authoring DVDs Objectives After studying this chapter, you will be able to: Specify a DVD disc format. Select and include video programs. Add special sound track and text features. Develop a disc organization. Design the look and sound of a disc. Create menus for accessing disc features. Prepare a disc project for replication. (Sue Stinson) 465

2 466 Video Digital Communication & Production About Authoring DVDs Authoring is the name given to the process of creating DVD video discs for playback by computers or DVD players. This process is not a simple mechanical transfer like making a videotape, but a multistep activity that requires planning, craftsmanship, and creativity. In that sense, a video editor is the author of a DVD much as a writer is the author of a book. Aids to Navigation A DVD such as a feature movie release contains not one program but several each one recorded at a different location on the disc. (See the sidebar for a typical example.) DVDs provide immediate access to any program on the disc; within each program, they allow jumping to predetermined points (called chapters). Often, they also force viewers to watch certain obligatory Figure Though the FBI warning is only a single program shot, it is technically one of the programs on the DVD. programs, such as the standard FBI warning screen, Figure When playing commercial DVDs, notice that some elements will not let you exit before they have finished. To provide random access to programs and chapters, DVDs are equipped with screens containing menus much like the user interfaces in computer programs. By selecting and clicking menu items, viewers can navigate through multiple displays to fi nd and access the programs, chapters, and special features they want. Creating this navigation system is a major part of DVD authoring. In this respect, DVD authoring is similar to Internet Web design, though usually simpler. Design Elements Most DVDs are meant for entertainment; and even instructional and promotional products are intended to be as lively as possible. To make them interesting, their menus can include moving images and musical backgrounds. Programs and graphics can be designed to carry out the theme of the disc, Figure Even sound effects (such as bells or camera shutter clicks) are sometimes added to indicate that selections have been made. Designing the graphics, video elements, titles, music, and sound effects for the DVD can be as creative as editing the programs on it. Technical Matters DVD authoring also has a technical side. Since programs may be played on different video displays using different TV standards, the Figure Most DVD authoring programs include menu templates. (Ulead)

3 CHAPTER 23 Authoring DVDs discs must be set up to refl ect these differences. Also, they may be played by people speaking different languages, so alternate soundtracks may be selectable by viewers. Additional soundtracks may also carry commentaries by the director or others connected with the program. Different sets of titles are often provided for foreign language translation or closed captioning. Each set can be selected and turned on or off by the viewer. Security Issues Because DVDs are digital, they are easily duplicated. To hinder the production and sale of pirated copies, DVDs can be equipped with two types of safeguards. To discourage sales in unauthorized markets, they can be regionally encoded, so that discs will work only in players sold in their own region, Figure The United States and Canada make up Region 1. To prevent all unauthorized duplication, discs can be encoded with copy protection, which either makes duplicates unwatchable or prevents copying altogether. Regional encoding and copy protection are optional; but setting the TV standard is not. The various TV systems, notably NTSC (in North America), PAL, and SECAM, are so different that discs made for one standard will not work at all with the others. 467 Preparing to Publish Even making the actual discs is not perfectly simple. For one thing, DVDs use a special encoding system that is different from the systems generally used for editing. Programs intended for DVD release must be translated into the MPEG encoding system. Some editing programs can, if desired, translate raw DV footage into MPEG format as they capture it. From there, individual copies can be made on computer drives that burn (record) DVDs. However, commercial discs made in large quantities are manufactured by a completely different process. For these discs, DLT (Digital Linear Tape) masters usually must be produced and sent to the commercial duplicating company. DVD Software Like video editing software, DVD authoring programs span a wide range of sophistication and complexity. The Ulead products cited in this book are typical. On the one hand, simple DVD authoring is included in VideoStudio (the editing program featured in Chapter 22), so discs for home use can be created without additional software. On the other hand, the DVD authoring program, Ulead DVD Workshop, Figure 23-4, includes capture operations for raw footage, a procedure usually performed with editing software. Figure DVD regions. (Ulead) Figure DVD Workshop is intended for advanced amateur and corporate users. (Ulead)

4 468 Video Digital Communication & Production Digital Formats: DV vs. MPEG Digital camcorders record footage in a particular format (mini-dv for most amateur and entry-level professional models); and video editing software stores captured footage in a format identical or very similar (typically AVI format in Windows-based computers). DVDs, however, use a different storage format called MPEG (named for the Motion Picture Experts Group, which devised it) because this format allows great data compression without notable loss in picture quality. (Video program fi les must be compressed because they contain enormous amounts of data.) A series of MPEG frames. (Symbolic representation: actual P and B frames do not look like this.) There are several versions of MPEG data compression, but their differences need not concern us here. For this reason, authoring software must convert fi nished video programs to MPEG format for inclusion on DVDs. Why not convert captured footage and edit in MPEG to begin with? Because frame-accurate cutting is diffi cult with MPEG since it does not store every video frame. In each second of video, MPEG designates some individual images as I-frames (short for intra-frames ) and stores all the picture information within each one. The frames between I-frames, however, are not complete images. All that is stored is the difference between that frame and the previous I-frame. These frames are labeled P or B; and a complete sequence if I, P, and B frames is called a GOP (Group Of Pictures). Some editing programs can work in MPEG by filling in data missing from a P or B frame with information from the previous I-frame. By contrast, mini-dv and similar formats use intra-frame compression for every frame, so you have a complete image wherever you decide to make an edit. Intra-frame compression is not used on DVDs because the resulting data fi les are larger than comparable fi les in MPEG format. In stand-alone DVD applications, Ulead offers three different programs of increasing sophistication. Within even the top-level program, however, selectable wizards, templates, and automated procedures can simplify the authoring process (at the expense, of course, of sophistication and originality). This chapter assumes that readers will create completely original, fully professional DVDs; so simplified, semi-automated procedures receive only minimal coverage here. DVD Workshop is used here for demonstration purposes. Though easy to learn, this program is sophisticated enough to create commercial-grade DVDs, complete with multiple language tracks, different sets of subtitles, regional encoding, and copy protection. In addition, its user interface is similar to that of VideoStudio, so readers of the previous chapter will soon feel comfortable with it. Authoring a DVD In summary, creating a DVD involves these essential processes: Selecting and adding the programs that viewers will play. Designing menus that reference both the programs and the commands to set them up for viewing (audio track, titles, screen shape, etc.). Placing buttons on the menus that allow viewers to navigate to other menus, set program parameters, and play programs. Linking those buttons to the screens, programs, or features that they are designed to access.

5 CHAPTER 23 Authoring DVDs 469 But before any of these processes can be undertaken, each new DVD must be set up. Figure The new project box. (Ulead) Configuring a DVD Project The opening screen in DVD Workshop resembles Figure Figure The opening screen of DVD Workshop. (Ulead) Like editing projects, DVD projects have project files, which are blueprints for the finished product. A DVD being authored is called a project, since program (or title ) refers to an individual video and there may be several on one disc. To begin a project, select New Project, which brings up the new project box, Figure Project Information Four pieces of information are essential. The project name and location enable your computer to store the project fi le. The media type specifi es which of several types of discs will contain the fi nished program and the TV system sets the type of TV. The remaining fields are optional, for your convenience. Under description, it often helps to list the names of the programs that will be on the DVD. A Demonstration DVD Project The wedding video introduced in the previous chapter was the third of three programs made from footage shot during a summer vacation in Ireland and England. The fi rst was a travelogue on Ireland and the second was a tour of an English palace. These three programs were brought together to create a single DVD about the vacation. This DVD provides all the examples used in this chapter. Ireland Blenheim The wedding. (Sue Stinson).

6 470 Video Digital Communication & Production Changing Information It is important to take care in supplying information for a new project. The project name and location can be changed if needed, but it is a good idea to establish a directory for it and keep all components there. Some materials, such as still photos, graphics, and music selections, may come from other sources. By copying them into the project s directory and importing them from there into your DVD program, you can keep all the working elements together. The media type and TV system cannot be changed. Projects encoded for DVD cannot be burned to other disc types, and vice versa. The TV system can be an issue if the fi nished program(s) will be shown outside your area. In that case, you will need to select New Project, set TV System to the alternate type, and rebuild the DVD for the different area. (Of course, the programs themselves must match the TV system selected for the DVD. You cannot, for example, place NTSC format programs in a PAL DVD project and expect them to play.) DVD Workshop defaults to DVD disc format and NTSC system type, the most common settings for North America. Figure Three programs have been imported from the computer hard drive to the options panel. The programs are added to the title list panel in the desired order. (Ulead) Placing Programs The first step in authoring a DVD is to select the programs that will be included on it, and the order in which they will be recorded. Program order is important. Although viewers can play programs in any order, the PLAY or PLAY ALL command buttons show the programs in the order recorded on the DVD. Selecting Programs Programs can be captured from camera footage or imported from computer fi les or DVDs. Here, three programs previously created in Ulead VideoStudio and fi led on the computer, are imported to the options panel and then placed in order on the title list, Figure The title list closely resembles the storyboard in the editing program and functions very similarly. Ulead DVD Workshop and other authoring applications use the word title instead of program. Program is preferred in this discussion to prevent confusion with the textual titles that are also components of a DVD. Creating a First Play Clip Note the empty square on the DVD storyboard labeled First Play. The program you place here will begin playing as soon as the DVD is started. Here, a short, moody segment on an Irish moor introduces the DVD, Figure A still from this shot will also form the background for several menus to be constructed later.

7 CHAPTER 23 Authoring DVDs 471 Figure Moor shot. The Irish segment will play fi rst. (Ulead) Figure The force fi rst play option. (Ulead) If you like, you can add a musical background to the opening, either by replacing an existing track or by adding a new track from a music library. As you can see from Figure 23-9, you can fine tune the music by adjusting its length to fit the video (or altering the video to fi t the length of the music), adjusting its volume level, and fading it in and/or out. In some cases, you may want to prevent viewers from skipping over this opening segment. In that case, checking the force first play box will ensure this, Figure Movie DVDs sometimes use this technique to make you watch their previews of other movies. Figure You can create a custom music (or other audio) track for your opening. (Ulead) Adding Features So far, organizing a DVD has not been much different from planning a release videotape. Now, however, you begin to add the selectable options and random access qualities that make the DVD so versatile. The first step is to divide each program into chapters. Creating Chapters A chapter is any piece in a program that can be selected directly from a menu. It begins with a frame of video designated as the chapter start and ends, by default, with the start frame of the following chapter. Later, in the menu creation process, chapters are named so that viewers know what they contain, but at this stage it is enough to designate them. Designating chapters There are several ways to mark the fi rst frames of new chapters. Perhaps the easiest is to scrub through the program until you reach the first frame of a new sequence (or any other division point you prefer) and freeze the program on that frame. Since the process has several steps, refer to Figure as you read. First, check the Locate I-frame box (1). Since the chapter identifi er is an image from the program, a frame other than an I-frame would give you an incomplete image (as explained in the sidebar Digital Formats: DV vs. MPEG).

8 472 Video Digital Communication & Production Figure An overview of the screen, showing the steps required in chapter creation. 1 Check the Locate I-frame box. 2 Find the fi rst frame of the new chapter. 3 Click add chapter. 4 A thumbnail identifying the new chapter appears in the chapter list. (Sue Stinson/Ulead). Next, use the slider to fi nd the fi rst frame of the new chapter (2). Then click Add Chapter (3). The thumbnail identifying the new chapter will appear in the chapter list (4). Changing chapter thumbnails Sometimes, the first frame of a chapter does not represent the chapter content adequately, or perhaps is it is simply not a high-quality image. For example, the first frame of the sequence, Dressing for the Ceremony, Figure 23-12, is not a very good image. To change it: Scrub through the sequence to fi nd a better image and pause there. Right-click on the chapter thumbnail to open a menu. Select Set Chapter Thumbnail. The thumbnail will change to match the image on the preview screen. It is important to understand that the chapter will still begin on the first frame of the sequence, as originally selected, even though its identifying thumbnail has been changed. Adding Alternate Audio Tracks It is common practice to supply DVDs with alternate sound tracks selectable by viewers. These are often foreign languages or director comment tracks. These tracks are added from computer fi les, Figure Later in the authoring process, you will provide viewers with information about these sound tracks and the means to select and enable or disable any

9 CHAPTER 23 Authoring DVDs 473 Figure The fi rst frame of the chapter is not particularly striking. Another frame from the sequence makes a better chapter thumbnail. (Sue Stinson/Ulead) Figure Adding or deleting an audio track. Selectors are note icons with + or - signs. (Ulead) Figure The language settings box is accessed from the options panel. (Ulead) one of them. Since the software does not know whether a particular track is a director s commentary or a Greek translation, the next task is to provide this information, Figure Adding Titles You may also want to add one or more sets of subtitles. These are usually foreign language translations or captions for the hearing-impaired. The process is essentially the same as adding audio tracks. After selecting the subtitle tab in the options box, you select Add/Edit Subtitles to open the subtitle work screen, Figure Adding subtitles can be a lengthy process. Sometimes it is better to write them all as a text file and then import them piece-by-piece to the appropriate place in the program. In Figure 23-16, the title has been typed directly into the subtitle field on the work screen. Note that the options on the right side of the work screen provide complete control over subtitle formatting. As with audio tracks, the subtitle tracks must be identifi ed. Selecting Specify language settings opens a work screen for doing this, Figure

10 474 Video Digital Communication & Production Figure The add/edit subtitles command. (Ulead) Figure The specify language settings selection is an icon that must be learned. (Ulead) Figure The subtitle work screen. (Ulead) Creating Menus Navigation is accomplished with menus. Organizing and linking these menus can be a simple matter of following on-screen instructions, or a complex process for a custom design. (See the sidebar A DVD Menu Tree for an example of a complex menu structure.) Altogether At this point, all the major content components of the DVD are in place: The opening. The programs. The program chapter divisions. The audio tracks. The subtitles. But as yet, there is no way for the viewer to navigate among these features and select the components desired for viewing the programs. Creating navigation tools is the next step in authoring the DVD. Templates and Wizards If you are using a template supplied with your DVD authoring software, creating a navigation system can be quite simple. The DVD menu in Figure was completed in less than ten minutes by following on-screen prompts provided by a menu-creation wizard. It was customized by replacing the template text with the program titles and dragging each program icon into a button on the menu. The small icons on the left allow viewers to play the previous program, the next program, or all programs in order. Designing the Menu Templates hide the organization of the DVD behind pre-structured menus. They can also make features like alternate audio tracks and subtitles difficult to access.

11 CHAPTER 23 Authoring DVDs 475 A DVD Menu Tree Here is a menu outline for the DVD of a typical feature fi lm. FBI Warning Studio Logo Preview One Preview Two Main Menu Play Movie Chapters Setup Screen Full screen Letterbox Sound Dolby 5.1 Stereo Language English French Titles English French Off Extras Commentaries The director The two stars Documentaries The Making of... Special Effects Trailers Teaser Theatrical trailer Music Video Deleted Scenes Scene 1 Scene 2 Scene 3 Cast Biographies Star 1 Star 2 Star 3 Director In addition, each screen must have buttons allowing the viewer to move back up the tree to higher level menus. Figure A blank menu template. The demonstration vacation DVD menu created from the template. (Ulead) If the DVD is at all complex, it will need custom menus, all designed from scratch and linked in a hierarchy. The Hierarchy The components of a DVD are organized in a hierarchy much like the table of organization in a business. If the organization of the vacation DVD were expressed that way, it would resemble Figure However, the structure of a DVD is created as a hierarchy of linked menus; so the vacation DVD organization actually looks like Figure For clarity, Figure includes only the wedding tree from top to bottom. Figure shows them in more detail.

12 476 Video Digital Communication & Production Figure A typical table of organization. Main Menu Setup Menu Ireland Blenheim Wedding Audio Titles Chapters Chapters Chapters English French English French etc etc etc Figure The vacation menu structure. Each of these graphic elements is called a button (whether button-shaped or not) and each button activates a playlist. Other, purely decorative graphic elements, are called objects. Menu Components Objects, buttons, and playlists are the building blocks of DVD menus. The links As shown in Figure 23-21B, the wedding menu (like the others) has certain features: Play, to start the wedding program. Home, to return to the main menu. Play previous, to start the previous program on Blenheim palace. Play all, to start with the Ireland program and play all three programs. Chapters, to access the chapters menu. Unlike other menus, this one lacks a play next button because the wedding is the final program on the disc. Objects Objects are images (still photos or graphics), frames copied from video, or text (whether program titles or menu commands). Objects are inert that is, clicking on them has no effect. A special type of object is called a placeholder. A placeholder is a spot on a menu template that will become an object when you drag a suitable element onto it. Although placeholders are not used in original menus, they are covered below, for completeness. Buttons Buttons are graphic elements that are linked to programs, commands, or other menus, Figure They are like switches: when activated, they turn on the items they are linked to. Buttons can take almost any form, from icons imported from a library, to custom graphics, to stills from videos or even tiny screens on which the linked videos actually play.

13 CHAPTER 23 Authoring DVDs 477 Figure Linked menus. A The main menu. B The wedding video menu. C The wedding chapter menu. D The start of a chapter. (Sue Stinson) A B C D Figure All the items except the background image are buttons. (Ulead) Figure The Ireland button is linked to the Ireland menu through the playlist. (Ulead) Playlists Playlists, as their name reveals, are lists containing one or more names identifying programs, menus, or commands in the DVD. Each button has its own playlist. When a viewer activates the object, the item(s) on its list will play. To see how this works, study Figure Ireland is a button on the main menu. Its playlist contains one item: MENU-01. As you can see from the inset detail, MENU-01 is the menu screen for the program on Ireland. So, activating the Ireland button causes the link in its playlist to open the Ireland program menu. If a playlist contains more than one item, each will play in order. Building the Menus Menus can be extremely sophisticated, with audio (usually music) that loops as long as the menu is on-screen. The buttons can be small

14 478 Video Digital Communication & Production screens in which the videos they link to are actually playing. Objects and buttons can move in a variety of CG effects. Each DVD authoring program accomplishes these tasks in slightly different ways, so our demonstration DVD project will stick to the more generic operations. At this point, the menu tree has been designed, and now each menu will be built, starting with the main one. In actually building menus, you will probably go through the sequence of placeholder-object-playlist-text for each item. Background First of all, we need a background. The First Play video includes a moody shot of a prehistoric tomb, so we capture a still from it as an object and scale it to fill the frame, Figure If we were working with a template, placeholders would be in position to receive objects. Though they are not present in our custom design, we will add them for demonstration purposes, Figure Buttons Now we are ready to place the buttons that will link to the individual program menus. (Assume that these menus have already been created and so are available to be linked.) See Figure We still need buttons for two commands: play all and setup. Play all is a standard button, automatically linked to the command to play all the programs on the DVD in order. Setup is not a Figure The background for the main menu. (Sue Stinson) Figure Placeholders added to the main menu screen. Figure Buttons added. Figure Utility buttons added.

15 CHAPTER 23 Authoring DVDs standard button, so we pick a button shape, open its playlist, and link it to the setup menu. (The buttons are in the button library. Two selections from that library are shown in Figure ) Figure The controls for the borders and links are below the screen. (Ulead) 479 Text So far, you know what the buttons activate but viewers do not (the titles on the program buttons are too small for easy reading). So the last step is to add text, using formatting commands very similar to those in most graphics and word processing programs, Figure Checking Your Work You will repeat this process for every other menu in the project. Before leaving each one, you should verify two important things: that menu components especially buttons do not overlap, and that every button has an appropriate link in its playlist. To do this, click the buttons highlighted in Figure Green borders will appear to show the boundaries of objects and buttons, and each button will display the item in its playlist. Figure Adding text completes the menu. Previewing Because DVD menu systems can be complex, it is prudent to preview your project before locking it up. Most authoring software includes a virtual DVD player that simulates all the functions of an actual player. To check your work, make sure that every button is linked to the appropriate element (program, menu, or command). Play every selection on the DVD, looking for small problems with audio tracks, graphic elements, and the like, Figure Archiving There are three ways to store your DVD project permanently. Most authoring programs offer all three methods. Completing the Project With the menu system designed and the individual menus created, only two steps remain: previewing the DVD and preserving it permanently by archiving it. DVD burning The first is to simply burn a disc, that is, create an actual DVD of your program. This option is fi ne if you plan to keep the project on your computer hard drive, or else make a few discs and discard the original materials. Though you can load the DVD fi les back onto your computer, you can only play them as you would in a DVD player. You can no longer work with them. Creating a disc image file A disc image file is a fi le that contains all the materials used in your DVD project. With it, you can reopen the project for additions or revisions and prepare a new DVD. Since you can

16 480 Video Digital Communication & Production Figure The preview screen has a virtual DVD remote control. (Ulead) Change Is the Only Constant It is wise to archive your DVD in a format that can be reopened and worked on in the future, because recording and playback systems are always changing. Today s popular format may be unplayable in a few years, like the once-universal 78 rpm shellac audio discs (they were called records ), Figure As long as your software can read your working fi les (and your operating system can run your software) you will be able to reformat your DVD for whatever playback medium comes along. Figure The 78 rpm record was once the standard audio medium. record a disc image fi le on a DVD as a data fi le, you can upload it whenever you wish to use it. That way, you can clear your drive of the very large fi les generated by DVD projects. Creating a digital linear tape Digital linear tape ( DLT ) is the standard format for supplying DVDs to commercial duplicators for mass production. Although you probably will not have a DLT machine, you can instruct your program to store the DVD in DLT format, which can then be copied to disc as a data fi le and delivered to a facility with DLT capabilities.

17 CHAPTER 23 Authoring DVDs 481 Chapter Review Answer the following questions on a separate piece of paper. Do not write in this book. 1. To discourage piracy, DVDs are often equipped with two types of security measures: and copy protection. 2. True or False? To prevent viewers from skipping over the opening segment, the force first play option is selected when creating the DVD. 3. To permit the viewer to navigate the DVD easily, you must create. 4. Buttons are graphic elements that are linked to programs when activated, they the items they are linked to. 5. Your project can be archived by burning a CD, creating a fi le, or creating a DLT (digital linear tape). Technical Terms Authoring: The process of designing and assembling DVDs. Button: An element on a DVD menu that, when activated, links to a program, a menu, or a function. Chapter: A designated section of one program on a DVD. Copy protection: A system of encoding designed to prevent copying DVDs. Disc image file: A computer file containing all the components of a DVD project. Digital linear tape (DLT): A DVD storage file format for recording on a special half-inch tape that will be the master for mass-producing DVDs. DVD: A computer disc format originally designed to hold movies, but now used for all-purpose data storage, too. First play: A menu or program that plays automatically when a viewer starts the DVD. I-frames: Intra-frames that contain all the image data. (See MPEG). Intra-frame compression: A digital video recording system that saves storage space by condensing and recording the data for every frame. Menus: In DVD authoring, screens displaying buttons for navigating to other menus, programs, or functions. Mini-DV: The most popular recording format for small camcorders. Uses intra-frame compression. MPEG: A recording format that records full information only for selected frames (called I-frames ), plus partial information for other frames. NTSC: The TV standard used in North America and Japan. Other major standards include PAL and SECAM. Object: An item on a menu that does not link to anything. Placeholder: On a menu template, an indicator of where an item should be placed to make it a button. Playlist: A list, for each button, containing the names of one or more menus, programs, or functions activated by that button. Project: The process of authoring a DVD. Regional encoding: Code on a DVD that permits it to be played in only one designated world region. Scrub: To move quickly through a program by dragging a handle along a track below a preview window. Template: A pre-designed menu that is customized by substituting appropriate buttons and text. Text: Anything written on a DVD menu. Title: In DVD authoring, any program or menu. (A common term, but not used in this sense in this book.) TV standard: A broadcast system, such as NTSC, SECAM, or any of several varieties of PAL. Wizards: Mini-programs that guide users through the menu creation process step by step.

18 482 Video Digital Communication & Production As a chapter thumbnail, this image may represent sequences captured at the end of the wedding day. (Sue Stinson)