5. Archiving, Encoding, and Burning
iMovie's purpose is to create a movie, which can be published to a Web page, sent to an iPod or Apple TV, or distributed in other ways. iDVD's purpose, however, is to create a project that can be burned to a DVD disc. It contains high-quality video and audio that will play on a consumer DVD player. Without the disc-burning step, iDVD is pretty much just an interesting exercise in customizing a user interface.
True to form, the process of burning a disc is simple: click the glowing Burn button, insert a recordable DVD disc (DVD-R, DVD-RW, DVD+R, or DVD+RW), and go outside to enjoy the sunshine for a few hours. But getting to that point, while not difficult, involves a few choices that determine the amount of data that can be stored on the disc and the quality of the finished project.
Creating a Project Archive
Burning a DVD takes a lot of hard disk space and processing power. Some people choose to build a project using one Mac (such as a laptop), and then burn the DVD on another computer (such as a desktop Mac, which boasts a faster processor). Or, perhaps your Mac doesn't include a SuperDrive. In these situations, create an archive of your project that can be copied to another machine.
If you're planning to burn a disc on your computer but don't need an archive, skip ahead to "Choosing an Encoding Setting."
To create a project archive:
- Choose Archive Project from the File menu. If your project isn't saved, iDVD asks you to save it. To continue, click OK in the dialog that appears; otherwise, click Cancel.
- In the Save As dialog that appears, choose a location for the archive and, optionally, change its name (
Figure 5.1 When you save your project as an archive, the Save As dialog contains archive-specific options.
- Enable or disable the following options. The estimated size of the archive appears to the right and changes based on your choices.
Include themes. If your project uses themes that aren't likely to be on another computer (such as third-party themes you purchased, or favorite themes you designed), enable this option to copy the necessary information to the archive. If you leave this disabled, but your project contains custom elements, an error dialog appears on the other computer when you open the archive (
Figure 5.2 Choose Include themes when saving an archive to avoid an error dialog like this one.
- Include encoded files. iDVD can encode material in the background, which reduces the time it takes to burn the disc (see "Choosing an Encoding Setting" on the next page). Including these files means it will take less time to burn the project on another machine, but it also makes the archive size larger.
- Include themes. If your project uses themes that aren't likely to be on another computer (such as third-party themes you purchased, or favorite themes you designed), enable this option to copy the necessary information to the archive. If you leave this disabled, but your project contains custom elements, an error dialog appears on the other computer when you open the archive ( Figure 5.2 ).
- Click Save. After a few minutes, depending on the size of your project, a new archive file is created.
Choosing an Encoding Setting
iDVD employs three encoding methods: Best Performance, High Quality, and Professional Quality.
To choose an encoding setting for the current project:
- Choose Project Info from the Project menu or press Command-I.
- Choose an option from the Encoding pop-up menu (
Figure 5.5 The encoding options are located in the Project Info window, as well as in iDVD's preferences.
To choose an encoding setting for new projects:
- Open iDVD's preferences and click the Projects icon.
- For the Encoding setting, click the radio button beside the type of encoding you wish to use.
Best Performance provides up to 60 minutes of video and shorter burn times than High Quality. iDVD encodes the video while it's running, whether you're doing something else in iDVD or working in another program ( Figure 5.6 ).
Figure 5.6 With the Best Performance setting enabled, iDVD encodes movies in the background. The Project Info window reports on the progress.
If your project exceeds 60 minutes, or you want to make sure you're getting a higher quality encoding than Best Performance, use the High Quality mode. After you start the burn process, iDVD examines the video to determine where it can apply different levels of compression (a process called Variable Bitrate, or VBR, encoding).
Professional Quality uses the same encoding algorithms found in Apple's pro-level applications. Like High Quality, it uses VBR, but it takes two passes through the footage to optimize the compression. Professional Quality projects tend to feature richer colors and better reproduction than High Quality projects ( Figure 5.7 ).
Figure 5.7 Professional Quality projects tend to produce richer color fidelity.
Burning the DVD
Before you click the Burn button, make sure you have enough hard disk space available: at least twice the amount the project occupies. You can view your project's size and the free space on the hard disk that contains your project by choosing Project Info from the Project menu.
To change the name of the burned disc:
- Choose Project Info from the Project menu, or press Command-I. The Project Info window appears (
Figure 5.9 In the Project Info window, change the name of the disc when it's inserted in a computer.
- Type a new name in the Disc Name field. After the disc is burned, this name is used when the DVD is mounted on a computer's desktop.
- Close the window to apply the change.
To locate a missing asset:
- Choose Project Info from the Project menu, or press Command-I to display the Project Info window.
- Scroll through the asset list to find entries with a zero (0) in the Status column (
Figure 5.10 Use the Project Info window to locate missing assets.
- Double-click the missing asset to bring up the Missing Files dialog.
- Select a file in the dialog and click the Find File button.
- Locate the file and press OK. The Status column displays a checkmark. Note that for missing imported videos, you need to re-link the video and audio portions (just point to the same file).
- Click OK to exit the dialog.
To burn the DVD:
- Click the Burn button; the iris reveals the glowing Burn button that's been hiding under iDVD's interface (
Figure 5.11 You need to click the Burn button only once to start the process (some earlier versions required two clicks). So, really, there's no good reason to hide the button behind the safety iris—except that it's cool.
Figure 5.12 If errors are found before burning, iDVD gives you the opportunity to fix or ignore them.
- A progress dialog appears that identifies the stages of the process (
- Stage 1: Prepare. iDVD ensures that it has everything it needs to continue burning.
- Stage 2: Process Menus. Buttons, motion menus, and other menu interface elements are rendered and encoded.
- Stage 3: Process Slideshows. Slideshow photos are resized and compressed as needed. If you've specified slideshow transitions, they are rendered separately during this stage.
- Stage 4: Process Movies. Depending on which encoding method you've chosen, this stage usually takes the longest.
- Stage 5: Burn. The footage is multiplexed, which combines the audio and video data into a single stream that can be read by DVD players. Burning is when the laser actually etches your data into the surface of the disc.
Figure 5.13 The disc burning process goes through five stages of encoding and writing data to disc. The small preview helps you determine how far along the process has advanced.
Saving as a Disc Image
Until iDVD 5, you needed to own a Mac with an Apple-supplied SuperDrive to burn iDVD projects. It wouldn't work with third-party external burners.
Now, that restriction is gone. However, there are still occasions when you want to save the project as a disc image, which effectively "burns" your project to the hard drive. For example, you may want to burn a DVD from that disc image on another computer, or mount the image on your desktop and preview the final project using the DVD Player application.
To save as a disc image:
- Instead of clicking the Burn button, choose Save As Disc Image from the File menu, or press Command-Shift-R (
Figure 5.15 "Burn" a disc image to your hard drive.
- Choose a location on your hard disk to save the disc image; make sure you have plenty of free space.
- Click the Save button. iDVD follows the same procedure as when it burns a disc.
To burn a DVD from a disc image:
- Launch Disk Utility (located in Applications > Utilities).
- Drag the disc image from the Finder to the left-hand column (
); or, choose Open from the Images menu.
Figure 5.16 Drag a disc image to Disk Utility to burn its contents to a DVD.
- Select the disc image in Disk Utility and click the Burn button.
- Insert a recordable disc.
To play a disc image using DVD Player:
- Double-click the disc image to mount the disc as if it were a physical DVD.
- Launch the DVD Player application.
After the Burn
When the burning process is complete, iDVD spits out the DVD disc and asks if you'd like to make another copy ( Figure 5.17 ). If so, insert a new disc; otherwise, click Done.
Figure 5.17 If you're creating multiple copies of the same disc, burn them in succession so you don't have to go through the encoding stage each time.
Here are a few other suggested things to do while you're in your cooling down period.
Test your project
Just because you have a shiny disc in hand doesn't guarantee that it works. Test it on your own machine using DVD Player. Test it on friends' Macs and PCs, and insert it into your consumer DVD player. Test, test, test, or you may find yourself singing, "To every season, burn, burn, burn..."
Delete encoded assets
If you don't need to burn another disc, you can free up some hard disk space by deleting the project's encoded assets, which are stored in the project file.
Create an archive of the project for offline storage to make sure you have all of the original footage.
To delete encoded assets:
- From the Advanced menu, choose Delete Encoded Assets.
If you want to make copies of the DVD without going through the iDVD burning process, use Disk Utility or other software such as Roxio's Toast (www.roxio.com).