Superimposing and Compositing > Using keys to superimpose and create composites
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Using keys to superimpose and create composites


Adobe Premiere provides 15 keys (methods for creating transparency) that you can apply to a clip to create transparency in many different ways. You can use color-based keys for superimposing, brightness keys for adding texture or special effects, alpha channel keys for clips or images already containing an alpha channel, and matte keys for adding traveling mattes or creative superimpositions.

In some cases, you can make keying easier by using a temporary brightly colored background matte. A bright color underneath the image you are keying makes it easier to see areas of transparency. See Adding a background matte.

To apply a key to a clip:

1 Select the clip in a superimpose track (Video 2 or higher).

2 Do one of the following:
  • In the Effect Controls palette, click Setup next to Transparency.
  • Choose Clip > Video Options > Transparency.

    • 3 Choose a key from the Key Type menu.

    The default key type is None. At this setting, no part of the superimposed image is keyed out. However, you can set the opacity of the image by adjusting the opacity rubberband in the Timeline (see Using the Video Opacity rubberband). You can also use the None key type for creating split screens and other effects where a portion of the underlying image is visible (see Creating split screens).

    4 Click one of the following icons to view transparency:

    Places a black or white background behind the keyed-out image. Click to toggle between black and white.

    Displays a checkerboard pattern to help you view transparency in areas that may be difficult to see against a solid background or against the actual underlying image. Click to reverse the checkerboard pattern.

    Displays the actual underlying image in your project. This view may be slower to display when you drag the preview slider under the Sample box.

    5 To zoom in on the image in the Sample area, select the Zoom icon (), and then click an area of the image. Click again to increase the zoom. To zoom out, hold down the Alt key (Windows) or the Option key (Mac OS) and click the image with the Zoom icon selected. To view other areas of the image at the same zoom, select the Hand icon () and drag the image. On Mac OS only, you can click the Collapse icon () to move the image to the Program view in the Monitor window.

    6 Select the following options as needed:
  • Reverse Key to reverse transparent and opaque areas (available only for certain keys).
  • Drop Shadow to add a 50% gray, 50% opaque shadow to opaque areas (available only for certain keys). The shadow is placed four pixels below and to the right of any contiguous opaque region. Drop Shadow is most effective for titles or simple graphics.
  • Mask Only to produce a special effect that displays only the alpha channel matte view of the clip (available only for certain keys).

    • 7 Adjust the transparency sliders and select other options as described in the following sections on individual keys.

    8 Drag the slider beneath the Sample box to view your transparency settings across the duration of the clip.

    9 Click OK to apply the settings to the clip.

    Note: You can quickly access the transparency settings for a clip by clicking Setup next to Transparency in the Effect Controls palette.

    Superimposing and Compositing > Using keys to superimpose and create composites

    Related subtopics:

    Using the Chroma key type
    Using the RGB Difference key
    Using the Blue Screen and Green Screen keys
    Using the Non-Red key
    Using the Luminance key
    Using the Multiply and Screen keys
    Using the Alpha Channel key
    Using Black Alpha Matte and White Alpha Matte keys
    Image Matte
    Difference Matte
    Track Matte