User guide

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Chapter 5, Defining Your Adobe Premiere Settings
$ Variable bit rate (VBR) Video is compressed at varying data rates based
on the complexity of the video. The data rate you select is used as the
average target data rate for the compression.
4 Drag the Data rate slider until your desired data rate is displayed. You can
also use the arrow keys (left, right, up, and down arrows) to select a precise
value. The higher the data rate you select, the better the video quality will
be.
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¡Important The maximum recommended DVD-compliant data rate is 7.0
Mbits/sec (0.83 MBytes/sec), which should give you good results with most
DVD authoring programs. If you select a higher data rate, be aware that it
may not be supported by your authoring program. For charts of
recommended data rates, see “Recommended MPEG data rates for
distribution on DVD-R or CD-Ron page 267.
5 You can customize the GOP structure of the MPEG-2 compression as
follows:
$ GOP length Determines the number of frames in the GOP (Group of
Pictures).
$ Subgroup length Determines the subgroup length of B-frames and/or
P-frames in the GOP, after the initial I-frame. A subgroup of 3 appears as
“BBP,” a subgroup of 2 appears as “BP,” and a subgroup of 1 gives you
only P-frames after the initial I-frame.
6 Click OK to save your settings.
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When selecting the data rate for a Matrox codec, be aware that a megabit (Mb) is equal to
1,000,000 (1000 × 1000) bits, and a megabyte (MB) after binary conversion is equal to
1,048,576 (1024 × 1024) bytes.