Apple Final Cut Express HD - Manual (Page 683)

Chapter 48 Video Filters 683
IX
Matte Choker Usually used in conjunction with a keying filter to manipulate the
edges of the key. The Edge Thin slider in the Matte Choker is often
used instead of the Edge Thin slider in the keying filter because it
can produce a more realistic result.
When you use the Matte Choker, moving the Edge Thin slider to
the right gradually eats into marginally keyed areas of a filter,
eliminating fringe and smoothing out the edges of your matte.
When you move the Edge Thin slider to the right, marginally keyed
areas of a clip are expanded, spreading out the matte and filling in
holes in your foreground image that may have been created by the
keying filter you’re using.
Matte Chokers always appear after the keying filter in the Filters
tab. Matte Chokers are also commonly used in groups. The first
Matte Choker eliminates the fringing in the areas you want to key
out, but may create holes in the foreground image. The second
Matte Choker, applied in reverse, fills in these holes to make the
foreground image as solid as possible. More Matte Chokers can
further fine-tune your key.
Soft Edges Blurs the four edges of the clip individually by the specified
amount to create an old-fashioned vignetting effect. Each of the
four edges of your clip can be individually adjusted using the Left,
Right, Top, and Bottom sliders. The Dither and Gaussian checkboxes
are used to modify the quality of the blurred edge, and the Invert
checkbox allows you to toggle between masking out the edges
and creating a hole in your image.
Widescreen Generates a widescreen matte in the clip to create a letterboxed
image. The Type pop-up menu allows you to adjust the aspect ratio
of the top and bottom mask using standard academy ratios. The
Offset slider lets you move the affected clip up or down in order to
display the area that’s most important. The Border slider moves the
top and bottom of the letterbox inward by up to ten pixels. The
color controls allow you to specify a border color for the letterbox
other than black, and a Feather Edges checkbox blurs the edges of
the letterbox.
Filter Result