Importing Animations
Radius EditDV is capable of importing animations generated from any
program on any platform that is capable of generating a file type
supported by QuickTime.
There are two ways to render a QuickTime movie that can be used in
EditDV. One way is more direct, but there is a more roundabout way
that can yield better results.
The easiest way to render from an animation program is to render a
QuickTime movie, using the appropriate Radius SoftDV compressor.
The resulting movie can be used in EditDV just like any clip captured
from a DV camera.
When you wish to composite (superimpose) this animation onto ovideo
in EditDV, you can use the Chroma Key and Luma Key filters.
However, animation programs can provide a way to effortlessly and
perfectly composite animations onto video if the clip is prepared
differently.
Alpha Channels: Perfect Composites Without Filters
Most animation programs are capable of automatically generating an
alpha channel with your rendered movie. This invisible channel
effectively tells EditDV which pixels in each frame sould be transparent
(showing the background video through) and which should be opaque
(showing only the animated image).
Unfortunately, only one QuickTime compressor will keep this alpha
channel in the rendered QuickTime movie. It’s called Animation, and
you must use the Color setting “Millions+” (the “+” is the alpha
channel).
The Animation compressor is not a DV compressor. It will not play
back very smoothly in the Source monitor on any of today’s systems,
and will not play out to the DV device at all. What’s more, the file sizes
can be very large, much higher than the 3.6MB/sec rate of DV.
When clips rendered using this compressor are imported into EditDV,
they will composite perfectly onto any video track above them in the
Sequencer, without filters. However, you will need to update the VP
track before you can see your animation played back smoothly on the
DV device connected to the FireWire port.
Application Settings
Before choosing rendering settings for your animation, you must
identify capabilities of your animation application:
• Does the application support nonsquare pixels? If the application
can render the rectangular pixels used by formats like DV and D1
(ITU-R 601), you can be sure that your animation will not appear
squashed or stretched in EditDV. Look for settings like “D-1” or
“Pixel Aspect Ratio.”
• Does the application support field rendering? You can get smoother
results if the application supports field rendering. Most application
refer to this feature differently. Look for “Field Rendering,” “Field
Rate,” “Interlacing” or “Field Dominance.”
• Does the application support rendering at the NTSC frame rate of
29.97 frames per second? If the application treats NTSC as 30
frames per second, you may discover timing problems or frame
skipping, especially on animations longer than 30 seconds.
Assuming your application supports all of the features described above,
use the following rendering settings:
Frame Size: Frame size should be 720x480 for NTSC, or 720x576 for
PAL, whether you are using a frame aspect ratio of 4:3 or 16:9.
Pixel Aspect Ratio: The NTSC 4:3 pixel aspect ratio should match the
D1 aspect ratio of .91. The PAL 4:3 pixel aspect ratio should match the
D1 aspect ratio of 1.06. The 16:9 pixel aspect ratios should be .75 for
NTSC and PAL.
Frame Rate: 29.97 for NTSC, 25 for PAL.
Field Rendering: The correct setting is labeled variously as “Lower Field
First,” “Even Field,” or “Field 2 First.”
If there is a setting for Broadcast Safe colors, use it. It may change the
colors in your animation to comply with the limitations of television
technology.
QuickTime Compressor: If you wish to render directly to a DV codec,
use either the standard or 16:9 Radius SoftDV codecs in NTSC or PAL,
as appropriate. (If SoftDV is not installed and you are not rendering a
16:9 clip, you can use the “DV - NTSC” or DV - PAL” codecs that are
installed with QuickTime 3.0. They will work just as well in EditDV.) If
you wish to take advantage of alpha channel compositing, use
“Animation”, with Colors set to “Millions+”, at the highest Quality
setting.
Alpha Channel: “Straight” alpha channels (as opposed to
“premultiplied”) render best in EditDV. This setting is irrelevant if you
are rendering directly to a DV compressor.
If your application does not support features like field rendering and
non-square pixels, there are usually workarounds. For example, if your
application does not support field rendering, you can render at double
the normal framerate (i.e. 50fps instead of 25 for PAL), and set the clip’s
Speed to 50% in EditDV. When the VP track is updated, the clip will
appear to be field rendered.
If your application does not support non-square pixels, you should work
in the animation application with “square-pixel” resolutions and then
scale the rendered clips to DV resolutions. The square-pixel resolution
for NTSC and PAL is 720x540. For 16x9, it is 864x480 for NTSC and
1024x576 for PAL.
Pencil Tests
While developing the animation, you can render it at a low quality
setting for speed. Import that file into EditDV and make sure
everything is behaving as expected. Keep improving the original
animation, saving it each time with the same name, replacing the
previous file. The project will automatically update to include the newer
media. Repeat this process up to and including rendering the finished
media.
Author: Mike Jennings
Applies to Version(s): 1.5
Last Updated: 11/21/98
[ Learning Centre ] [ Troubleshooting ] [ Downloads ] [ Gallery ] [ Wishlist ] [ Links ] [ Email ]
© 2001, No One In Particular, Inc. This site is not affiliated with Autodesk Discreet .
Stealing from this site is prohibited unless you ask nicely.