Who doesn’t know about the famous green screen effect? Movies such as “The Matrix” and “Avatar” have already made film history with the use of these effects. Just about everyone knows about green screening – but how does the whole thing work and can the effects be reproduced using Video Pro X5? Using green screens, also known as chroma key techniques, is a lot easier than some might think.
However, it is actually only green screening if a green screen is used. It is also possible to carry out chroma keying in blue, red, or another color. The main thing is that the screen or surface is one color. But why is a green screen predominantly used? Even though blue screens are used now and then, green screens are nevertheless more widely used. Green is the optimal color because it is the easiest to isolate, since it is rarely found on the human body. Quite the opposite to blue. Blue eyes collide with the created effect and become transparent against a bluescreen. For this reason, the color green is preferred. You can see from this example that it is not a good idea to have the same color in the image as that of the screen. Whether the effect is applied to an image or video is irrelevant.
Now I will explain how the chroma key technique works in Video Pro X. The “background” , which should shine through, is located in the first track in the arranger. In the second track you will find the “foreground” , which is provided with the chroma key technique. To apply the effect, you must select the object in the second track and open the “Effects” tab in the Mediapool. Click on “Video effects” there and select the item “Chroma key”. Keep in mind that the “foreground” cannot be the same size as the “background”, otherwise the “foreground” will obscure the “background”. Should that be the case, you can change this via “Effects” > “Position/Size”.
The next step is to use the button “Stamp” . After activating, the image of the selected object will be incorporated into the overlaying scene. Nothing is transparent yet here.
Now there are two ways to make the background of the second track disappear. Either select the appropriate colors in “Hidden colors” or use the “Color” button and navigate the mouse over the color range that you want to be transparent in the preview monitor. As a result, the image with these colors becomes transparent. The application of the effect can be refined using the controllers “Threshold value”, “Transition range”, and “Antispill”, so that transitions to objects, for example, are displayed in focus. And you’re done – that was the entire secret behind green screening/chroma keying.