Video effects and transitions in Premiere Pro

Keying effects

Chromakey with the Ultra Key effect

The Ultra Key effect is GPU accelerated, for improved playback and rendering performance, in computers with a supported nVIDIA card.

Ultra Key effect parameters

Matte Generation

Controls the transparency of the source when keyed over a background. Values range from 0 through 100. 100 is fully transparent. 0 is opaque. The default value is 45.

Increases the opacity of light areas of the source image. You can use Highlight to extract details like specular highlights on transparent objects. Values range from 0 through 100. The default value is 10. 0 does not affect the image.

Increases the opacity of dark areas of the source image. You can use Shadow to correct a dark element that became transparent because of color spill. Values range from 0 through 100. The default value is 50. 0 does not affect the image.

Filters out colors in the foreground image from the background. Increases tolerance to variation from the key color. You can use Tolerance to remove artifacts caused by color shift. You can also use Tolerance to control spill on skin tones and dark areas. Values range from 0 through 100. The default value is 50. 0 does not affect the image.

Filters out noise, often caused by grainy or low light footage, from the alpha channel. Values range from 0 through 100. The default value is 10. 0 does not affect the image. The higher the quality of your source image, the lower you can set Pedestal.

Matte Cleanup

Shrinks the size of the alpha channel matte. Performs a morphological Erode (fractional kernel size). Choke Level Values range from 0 through 100. 100 represents a 9x9 kernel. 0 does not affect the image. The default value is 0.

Blurs the edge of the alpha channel matte. Performs a box blur filter (fractional kernel size). Blur Level values range from 0 through 100. 0 does not affect the image. The default value is 0. 1.0 represents a 9x9 kernel.

Adjusts the contrast of the alpha channel. Values range from 0 through 100. 0 does not affect the image. The default value is 0.

Chooses the balance point for the contrast value. Values range from 0 through 100. 0 does not affect the image. The default value is 50.

Spill Suppression

Controls the saturation of the color channel background color. Desaturates colors that are close to being fully transparent. Values range from 0 through 50. 0 does not affect the image, The default value is 25.

Controls the amount of spill that is corrected. Values range from 0 through 100. 0 does not affect the image. The default value is 50.

Adjusts the amount of spill compensation. Values range from 0 through 100. 0 does not affect the image. The default value is 50.

Works with the alpha channel to restore the original luminance of the source. Values range from 0 through 100. 0 does not affect the image. The default value is 50.

Color Correction

Controls the saturation of the foreground source. Values range from 0 through 200. A setting of zero removes all chroma. The default value is 100.

Controls the hue. Values range from -180° to +180 °. The default value is 0°.

Controls the luminance of the foreground source. Values range from 0 through 200. 0 is black. 100 is 4x. The default value is 100.

Difference Matte effect

The Difference Matte effect creates transparency by comparing a source clip with a difference clip, and then keying out pixels in the source image that match both the position and color in the difference image. Typically, it’s used to key out a static background behind a moving object, which is then placed on a different background. Often the difference clip is simply a frame of background footage (before the moving object has entered the scene). For this reason, the Difference Matte effect is best used for scenes that have been shot with a stationary camera and an unmoving background.

Replace a static background with Difference Matte

The Difference Matte creates transparency by comparing a specified still image with a specified clip and then eliminating areas in the clip that match those in the image. This key can be used to create special effects. Depending on the clip, it’s possible to use Difference Matte to key out a static background and replace it with another still or moving image.

You can create the matte by saving a frame from a clip that shows the static background before the moving object enters the scene. For best results, neither the camera nor anything in the background should move.

The following Difference Matte settings are adjusted in the Effect Controls panel:

Specifies whether the Program Monitor shows the Final Output, Source Only, or Matte Only.

Specifies the track to be used as the matte.

Specifies whether to center the foreground image or stretch it to fit.

Specifies the degree to which the matte must match the foreground in order to be keyed.

Specifies the degree of softness at the edges of the matte.

Note: The RGB Difference Key uses color to define transparency much as the Difference Matte uses a still image.

Specifies the degree of blur added to the matte.

Image Matte Key effect

The Image Matte Key effect keys out areas of a clip’s image based on the luminance values of a still image clip, which serves as a matte. The transparent areas reveal the image produced by clips in lower tracks. You can specify any still image clip in the project to serve as the matte; it does not have to be in the sequence. To use a moving image as the matte, use the Track Matte Key effect instead.

Define transparent areas with Image Matte Key

The Image Matte Key determines transparent areas based on a matte image’s alpha channel or brightness values. To get the most predictable results, choose a grayscale image for your image matte, unless you want to alter colors in the clip. Any color in the image matte removes the same level of color from the clip you are keying. For example, white areas in the clip that correspond to red areas in the image matte appear blue-green (since white in an RGB image is composed of 100% red, 100% blue, and 100% green); because red also becomes transparent in the clip, only blue and green colors remain at their original values.

Non Red Key effect

The Non Red Key effect creates transparency from green or blue backgrounds. This key is similar to the Blue Screen Key effect, but it also lets you blend two clips. In addition, the Non Red Key effect helps reduce fringing around the edges of nontransparent objects. Use the Non Red Key effect to key out green screens when you need to control blending, or when the Blue Screen Key effect doesn’t produce satisfactory results.

The following Non Red Key effect settings are adjusted in the Effect Controls panel:

Sets the levels of blue or green that determine transparent areas in the clip. Dragging the Threshold slider to the left increases the amount of transparency. Use the Mask Only option to view the black (transparent) areas as you move the Threshold slider.

Sets the opacity of nontransparent areas specified by the Threshold slider. Higher values increase transparency. Drag to the right until the opaque area reaches a satisfactory level.

Removes residual green or blue screen color from the edges of the opaque areas of a clip. Choose None to disable defringing. Choose Green or Blue to remove a residual edge from green-screen or blue-screen footage, respectively.

Specifies the amount of anti-aliasing (softening) that Premiere Pro applies to the boundary between transparent and opaque regions. Choose None to produce sharp edges, with no anti-aliasing. This option is useful when you want to preserve sharp lines, such as those in titles. Choose Low or High to produce different amounts of smoothing.

Displays only the clip’s alpha channel. Black represents transparent areas, white represents opaque areas, and gray represents partially transparent areas.

Remove Matte effect

The Remove Matte effect removes color fringes from clips that are premultiplied with a color. It is useful when combining alpha channels with fill textures from separate files. If you import footage with a premultiplied alpha channel, or if you create alpha channels with After Effects, you may need to remove halos from an image. Halos are caused by a large contrast between the image's color and the background, or matte, color. Removing or changing the color of the matte can remove the halos.

Use Background Color to specify the new background color when you want to change the color of a matte.

Remove a black or white matte

If you imported a clip that contains a solid black or white matte that’s premultiplied (merged into the RGB channels instead of stored in the alpha channel), you can remove the black or white background.

Track Matte Key effect

Move or change the transparent area with Track Matte Key

The Track Matte Key reveals one clip (background clip) through another (superimposed clip), using a third file as a matte that creates transparent areas in the superimposed clip. This effect requires two clips and a matte, each placed on its own track. White areas in the matte are opaque in the superimposed clip, preventing underlying clips from showing through. Black areas in the matte are transparent, and gray areas are partially transparent.

A matte containing motion is called a traveling matte or moving matte. This matte consists of either motion footage, such as a green-screen silhouette, or a still image matte that has been animated. You can animate a still by applying the Motion effect to the matte. If you animate a still image, consider making the matte frame size larger than the sequence frame size so that the edges of the matte don’t come into view when you animate the matte.

You can create mattes in various ways:

• Use the Title panel to create text or shapes (grayscale only), save the title, and then import the file as your matte.

• Apply the Chroma, RGB Difference, Difference Matte, Blue Screen, or Non Red Key to any clip and then select the Mask Only option.

• Use Adobe Illustrator or Adobe Photoshop to create a grayscale image and import it into Premiere Pro.

The Track Matte Key effect creates transparent areas in a clip that correspond to the luminance levels of another clip. Transparent areas reveal the image produced by clips in lower tracks. Exclude the matte clip from the output by selecting the clip and choosing Clip > Enable.

You can use the Track Matte Key effect to blur and obscure faces, license plate numbers, or other identifying features. Television programs use this effect to protect the identities of their subjects.