With a little imagination, the chroma key can be a very useful tool. With a clip art border that is filled with the same solid color, you can create your own frame to use as an overlay. You can even do this with a photograph of a frame or texture by either photographing it with a solid color or placing the solid color in after the fact in PhotoSuite.
A bright or neon green is the most popular solid color to use because it is a naturally uncommon color. If you want something green to show up, a bright blue is also a popular color.
Import the Base Video onto the Video Track
To create a Chroma Key effect, you need two layers of video. The bottom or base layer is the main video. This will probably be the setting for action in your video. Anything placed in the overlay track covers this layer. Only by making portions of the overlay transparent are you able to see the base layer.
Place a Photo or Video in the Overlay Track
Whenever you place video in your production, you are always given the option of placing a second or subsequent video or photo in the overlay track. You can make any of your video files or photos into an overlay. To make the Chroma Key effect work, you need to place a video or picture that has quite a bit of the same solid color in it. Import the file and select the option to place it on the overlay track.
Select More Settings
After you have placed a video or photo in the overlay track, it is the only picture you are able to see in the Preview window. Make sure it is highlighted and click on the More Settings icon in the Preview window to bring up the Settings window.
Tip
If your Settings window is docked, you are able to see these options any time your overlay is selected.
Select Chroma Key
The drop-down menu in the Settings window has several options. Select the Chroma Key option.
Notes
When you have an overlay selected, the settings window is set specifically for the effects you can apply to your overlay. Any one of the options in the drop-down menu can be selected and applied to your overlay. After you have been over the basics of the Chroma Key option, you should be able to apply and play with the other options with ease.
The luma key is similar to the chroma key because it creates transparency in your overlay. It differs because instead of using a color to create the transparency, it uses the lighter or darker areas of your overlay. For instance, by using the luma key on the robot in the example, I can make all the black or all the white on him disappear.
Key Term
Luma key A transparency effect based on luminance, or the exact luminance used for the transparency effect.
Set Key Color
When you have selected Chroma Key from the drop-down menu, you are shown the settings for the chroma key. Because the color is literally the key to the way this effect works, choosing the right color is important. The best way to do it is to use the eyedropper to sample the color from your overlay. After you have changed the color, everything in the overlay that is the key color becomes transparent. Well, almost everything. At this point, there are probably a few spots gone that you didn't want gone or maybe there are a few spots of color that weren't zapped by the chroma key. That's what the other settings are for.
Tip
It is very difficult to prevent a "shadow" of color around the parts of the overlay that are left after applying the chroma key. Two things can help a lot: First, make sure your solid color is as uniform as possible. If you are using cloth, make sure there aren't any wrinkles and try to get the lighting as consistent as possible. Second, when you use the dropper, try to get a mid-range portion of the color so the tolerance doesn't need to be set very high.
Set Brightness Tolerance
The brightness tolerance determines how light or dark the color has to be to be made transparent. The higher the tolerance, the more color disappears. The downside of this is that as you set the tolerance higher, you start to lose portions of the overlay that you want to keep. Play with this and the hue tolerance together until you have the best possible setting.
Set Hue Tolerance
The hue tolerance determines how different the colors in the overlay can be from the key color and still go transparent. As you get higher up the scale, the colors radiating from your key color (in respect to the color wheel) start to disappear until your overlay is gone entirely. Watch your Preview window carefully to find the best setting.
Set Position Settings
After you have set the Chroma Key settings as best you can, click on the Position icon in the Settings taskbar to bring up the Position settings. Here you can set several variables to adjust the position of your overlay relative to the base image. If your proportion is not what you expected, you can shrink or enlarge your overlay. You can also stretch it; in this case, I stretched the overlay slightly to cut out part of the overlay that wasn't covered by the green screen when I filmed. You can also stretch a border to exactly fit your aspect ratio.
Tip
Remember that these settings can be applied to any overlay, even the predesigned overlays within VideoWave. You can use a 4:3 border and stretch it to fit a 16:9 aspect ratio.
Set Motion Settings
When you have positioned your overlay, you can adjust the Motion settings by clicking on the Motion icon in the Settings taskbar. Select the way you would like the overlay to appear and disappear from your video. When you are satisfied with your settings, close the Settings window.
BEFORE YOU BEGIN
SEE ALSO
Launch VideoWave and Change the Production Settings
About the VideoWave Interface
Add Video Files and Photos to VideoWave
Add Special Effects to a Video
Add Overlays to a Video