Apple DVD Studio Pro 4 - Manual (Page 464)

While you cannot import any kind of a motion asset into a subtitle stream, you can
manually create an animation by adding a number of very short (one- or two-frame)
subtitles, each with a different graphic that shows the line at a different stage.
Typical text subtitles have little impact on the playback bit rate—on average they run at
around 10 kbps. When you use subtitles to create an animation, the impact on the playback
bit rate becomes substantial, and may force you to lower the bit rate of the video stream.
The DVD specification limits a subtitle stream’s bit rate to 3.36 Mbps (about the same as
some MPEG-2 video).
The easiest way to create a subtitle animation is to create an STL subtitle file and import
it. You can specify the exact duration and position of each graphic, as well as configure
the color mapping settings. See
Creating an STL Format Subtitle File for more information.
Creating and Importing Subtitle Files
Often you may want to create your subtitles outside of DVD Studio Pro. There can be
several reasons for this:
• To use a facility that specializes in creating subtitles and closed captions: This can be
especially important if you are including subtitles in multiple languages.
• To free up your DVD Studio Pro system: Typing a lot of subtitles takes a significant amount
of time, especially if you are using multiple languages. This is often a task that can be
started well before you start authoring the project.
• To be able to spell-check the text: Creating the subtitle text with a text-editing program
gives you the ability to take advantage of its spell-checking capabilities.
There are two approaches used to create subtitle files for import into DVD Studio Pro:
Use a single file with the text embedded in it or use a group of graphics files, one for
each subtitle, with a master file that controls which files appear at which time.
In both cases, the subtitle files can be opened with a text-editing program such as TextEdit.
This makes it easy to verify the file’s settings and make any necessary modifications. Be
sure to save the file in a plain text format if you do make any changes.
Using a Single Subtitle File
When you use the single file subtitle method, you specify a timecode for each subtitle’s
start and end, as well as the actual subtitle text. You can also embed commands that
affect how the text appears on the screen, such as the font, position, color mapping
settings, and fade in and fade out settings.
There are two disadvantages of the single file subtitle method:
• It requires your authoring system to have the correct fonts installed. This can be an
important issue when working with foreign languages that require special characters.
464 Chapter 19 Creating Subtitles