User guide

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Chapter 10, Using Matrox Axio with Video for Windows Programs
Overview
When using Video for Windows (VFW) programs to render material to an .avi
file, such as in the case of a completed video production or an animation, you can
use a Matrox codec to create a Matrox .avi file. For example, you may want to
render an animation to Matrox DV/DVCAM format so that you can record it onto
DV tape. You could also use your VFW program to render video to a Matrox .avi
file so that you can import the file as a realtime clip into your Adobe Premiere
Pro projects on Matrox Axio.
When rendering compositions or animations that have an alpha channel, you can
select a “+ Alpha” Matrox VFW codec to render to a Matrox uncompressed or
MPEG-2 .avi file that includes the alpha-key information. This .avi file will play
back in real time on your Axio system, and will be automatically keyed when you
place the clip in your Adobe Premiere Pro sequence.
The following sections explain the various settings that you need to make to
render material to a Matrox .avi file using a VFW program. For details on
exporting video from a Matrox project to an .avi file using Adobe Premiere Pro,
see “Exporting to a Matrox .avi file” on page 106. Using Adobe Premiere Pro to
export video on your Matrox Axio system lets you overcome the 2-GB .avi file
limit of VFW programs.
Remarks
• When you select the Desktop editing mode for an Adobe Premiere Pro
project, Adobe Premiere Pro works like a VFW program as explained in this
chapter.
• Speed changes are not supported on Matrox VFW .avi files with alpha.
• You can’t use Adobe Premiere Pro to render effects with alpha using the
Matrox VFW “+ Alpha” codecs because Premiere Pro does not preserve the
alpha-key information during the render. Instead, you should use Adobe
After Effects to render your effects with alpha to a Matrox VFW .avi file.
• Although Matrox has tested many VFW programs, there may be certain
operational limitations when using Matrox Axio with some of these
programs (as well as with untested programs).
Axio Installation and User Guide.book Page 230 Monday, July 14, 2008 8:00 AM