4.5

142Compressor User Guide
• Color Correct Highlights, Color Correct Midtowns, Color Correct Shadows: Corrects
white balance inaccuracies and creates color effects on the bright, midtone, or dark
areas of the video. Drag the sliders to set red, green, and blue values between –100
and 100.
• Fade In/Out: Adds a dissolve and a matte color at the beginning and end of the clip.
This effect has the following properties:
• Fade in duration/Fade out duration: Enter a time (use a decimal to specify tenths of
seconds) in the text field to set the duration of the fade-in and fade-out effects.
• Fade in opacity/Fade out opacity: Drag the sliders to set the opacity of the clip’s
video at the first and last frames. A value of 0.0 sets the clip video to be completely
covered by the matte color; a value of 0.5 sets the clip to be 50 percent covered by
the matte color; and so on.
• Fade color: Click the color well to set the fade-in and fade-out color.
• Custom LUT: Applies a custom lookup table (LUT) to the video. This effect can be used
to give your video a specific look. This effect contains the following properties:
• LUT file: Click the Select button to specify a LUT file to use for the effect.
• Color space: Use this pop-up menu to select the target color space for the video.
• Gamma Correction: Controls the range of brightness in an image. This effect can be
used to remove detail from an underexposed clip or to reduce the saturation of an
overexposed clip. Drag the slider to set gamma values between 0.1 and 4.0.
Note: Computers using different operating systems have different monitor settings. For
cross-platform viewing, correcting the gamma will improve the image for all platforms.
• Noise Removal: Reduces random flecks of noise in the video file, including noise
introduced by codecs. This effect allows you to blur areas of low contrast while
leaving high-contrast edges sharp, creating results that are imperceptible to the
human eye but that improve the final compression of the transcoded file. The effect’s
properties include:
• Apply to: Use this pop-up menu to set the channels from which noise is filtered.
Choose “All channels” to filter noise from all channels including the alpha channel.
Choose “Chroma channels” to filter noise from the two chroma channels (U and V)
in YUV.
• Iterations: Choose the number of noise-smoothing passes (between 1 and 4) from
this pop-up menu. For instance, if you choose 2 passes, the noise-removal algorithm
is applied to the media file twice. The file resulting from the of first pass is used for
the second pass, and so on, so that the more times a pass is performed, the fuzzier
the image becomes.
• Algorithm: Choose a noise-smoothing algorithm from this pop-up menu. Choose
Average to modify each pixel’s color by taking an average of pixels around it,
including its own color value. Choose Replace to modify each pixel’s color by taking
an average of pixels around it, while ignoring its own color value. Choose Merge to
modify each pixel’s color by taking a weighted average of surrounding pixels and
itself (with the pixel’s own color value given greater weight).
• Sharpen Edge: Sets the contrast around object edges. This effect can counteract
the softening caused by noise removal or blurred source material and increase the
perception of sharpness in the video. However, note that too much of this effect can
make video look grainy. Drag the slider to set sharpening between 0.0 and 100.0.