User`s guide

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Special Topics
Captioning a Commercial Spot
If you are captioning a short commercial this issue is very important. If you do not do it right the
first closed caption will not appear when your commercial is edited into the broadcast video
stream since the caption data associated with your commercial precedes your actual video
content and will not be there when your video is played.
When you export a DV movie with closed captions you should specify the lower limit for the
closed caption data. This is necessary because all of the closed caption data for certain types of
captions such as Pop-on must precede the display of the actual closed caption itself and for Roll-
up and Paint-on closed captions some caption data is placed a few frames before the start of the
caption's display.
If you are using pop-on captions and your movie time code starts at 0:59:00:00, your video
content starts at 1:00:00:00 and the first closed caption appears at 1:00:01:00, which is one
second into the video content, the actual closed caption data is placed into the DV movie before
the caption is scheduled to pop on at 1:00:01:00. In this case you would set the Caption Data
Lower Limit to 1:00:00:00 to force MacCaption to begin putting the closed caption data into the
movie no earlier than time code 1:00:00:00.
If you do not set a lower Limit within the actual video content area, you may lose the first
caption when the beginning of the video is edited out later.
Without the Caption Data Lower Limit the caption data might be placed a number of seconds
before the closed caption is scheduled to be displayed and the closed caption data could occupy
the portion of the movie containing bars and tone, the slate, or the countdown. Setting Lower
Limit assures that all of the closed captioning data is placed into the actual video content area of
the movie.
Within MacCaption, during closed caption generation the Message Window will display the
unadjusted time code of the first closed caption data byte. If this value is less than the value of
the Caption Data Lower Limit the closed caption data is automatically readjusted during movie
export to start at the Caption Data Lower Limit. If some adjustment is required the first and
possibly a few subsequent captions may not appear exactly where they have been timed to
appear.
As with all closed captioning be sure to verify the accuracy of your work by viewing a playback
of the final product.