User`s guide

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First option is straight forward. We will explain how to use the second method in detail in the
following sections. The advantage of the second method is that the captioner does not have to
use MacCaption software on the NLE system; and after exporting the black video, can send it to
the computer having the original video inside the NLE system which might be at a completely
different location.
Choose Your NLE System: Using the Preferences NLE Tab you can change the image file data
generation lines. You must specify the type of NLE system you are using in the Preferences
NLE Tab. You must do this before proceding to the next step.
NLE 720x486 Videos
Use the Black 720x486 NLE Movie with Closed Captions option under the File Export menu
to add closed captions to video stored in the NLE 720x486 format. The NLE processing mode
creates a new QuickTime movie using the codec of your choice. Each frame within the movie is
mostly black with a couple of lines of gray scale information towards the top of each frame and a
couple of lines of gray scale information towards the bottom of each frame. These lines are the 2-
D pictorial representation of VBI (Vertical Blanking Interval) line 21 closed caption information.
When exporting the black video, choose the Codec used by the NLE system that is going to
import the black video, otherwise choose Animation Codec.
This black 720x486 movie is then imported into your non-linear editing system, where through
the use of a picture-in-picture effect or crop effect, two of its lines are merged with your video
program material. On output, the NLE maps the closed caption information to line 21 of the VBI.
The NLE must support a 720x486 pixel frame size for this to work properly. Video editing
hardware from Avid, Media 100, Matrox and Pinnacle Systems, among others, supports this
capability.
The 720x486 Black Video also contains frame sync indicator text.
The NLE processing mode cannot be used to add closed captions to a DV movie.
Avid Media Composer
This is because
the image size of the DV format is 720x480 pixels and a size of 720x486 is required to properly
handle closed caption data in picture form.
To output Black Movie with Closed Captions for Avid media composer, the MacCaption user
must select the QuickTime with Avid Meridien Compressed codec set to Millions of Colors.
(No alpha channel required)
Download the Avid codecs from www.avid.com