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Motion Masks in DVD Studio Pro 2Creating buttons with moving mask shapes and modifying button effects
I can't even begin to speculate why Apple chose not to include a simple method for applying motion masks to buttons in DVD Studio Pro 2. It's an otherwise full-featured DVD creation program, and it does have the capability to work with motion masks. Nevertheless, in order to get this thing to work, at present, you're going to have to perform a little surgery to extract an existing motion mask and replace it with your own. The process isn't all that difficult, but it is invasive. As with all techniques of this nature, I advise you to make a backup of your software before proceeding and not to attempt this process while you're in the middle of a paying project.
Also before we get started, if you haven't already, you might benefit by going back and reading our previous tutorials covering DVD Studio Pro 2. They are as follows:
- General DVD Studio Pro overview and walkthrough
- Review and overview
- General DVD issues, targeted specifically for graphic designers or those unfamiliar with the format
- Working with highlights, part 1
- Working with highlights, part 2
- Customizing masks (zoom masks), part 1
- Customizing Masks, Part 2
- Fixing Color Shift in Still Menus
Creating your motion mask
The mask itself can take any form, provided you keep a few things in mind. First, just as with still masks in your button shapes, motion masks use luminance values to determine which portions of your asset will show and which portions will be masked, revealing your menu background. Black masks your asset; white reveals your button asset; and various shades of gray reveal portions of your asset as semi-transparent.
So let's say we create a mask like the simple example below. (Click the play button to watch.)
In that case, the asset in DVD Studio Pro will be invisible at first (meaning that, essentially, your button is invisible). Then the asset will appear through the white slits. Then, as the "doors" of the mask slide open, the entire asset will be revealed. So let's say my menu background is a brushed metal texture and my asset is time-lapse footage of clouds. Here's what I'd see as the "doors" of my mask open up. (I'll show you a full-motion version at the end of the article so you know what to expect.)
Simple enough, right?
Incidentally, feel free to download the mask example above to use in your project as you follow along. To do that, click the button on the lower right of the movie, and select "Save as QuickTime movie." This sample movie isn't anything spectacular, but it will work fine for experimentation purposes.
Aside from the actual creation of the mask elements, the other considerations are fairly elementary. First is timing. Obviously you'll need to time your motion mask to coincide with whatever action, if any, is happening in your menu. You'll want to sync up the timing to the duration of your motion menu. And you might also want to "close" the mask back up at the end, especially if you're using a looping menu.
The dimensions and aspect ratio of the mask are two more considerations. The larger the file you use for your mask, the higher the quality. You don't, after all, want to create a dinky mask and expand it up to fit a large button, as you'll experience aliasing problems. And you might want to take aspect ratio into consideration. In DVD Studio Pro, you'll be able to scale your mask along with your asset, in which case you might experience undesirable distortion of the mask. But these are just cosmetic considerations. There's no such thing as a "wrong" shape or size for your mask.
And, finally, there's the question of format. Save your mask as a QuickTime movie. The specific codec shouldn't matter, though I haven't tried it with all of the available codecs. (Note that, occasionally, when opening projects in DVD Studio Pro that use a custom motion mask, you may receive an "incompatible format" warning, but this is a false warning; the DVD will burn and play back just fine.)
Once you create your mask, make a duplicate so that you have an extra copy in case something goes wrong. Then you're ready to do a little prep work in DVD Studio Pro itself.
Related Keywords:apple, dvd studio pro 2, masks, motion masks, buttons, shapes, motion shapes, quicktime
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