Processing and Formatting Effects > A/V Tools > FX Tools > 
Generating a High-Contrast Matte
 
 
 
NoteNot applicable to Backdraft Conform.

The Auto Matte command generates a high-contrast matte from a clip.

To generate a high-contrast matte:

  1. Select FX from the A/V Tools box, and then click Auto Matte.

    The Auto Matte menu appears.

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    (a) Min field  (b) Gain field  (c) Max field  

  2. Set the values in the Minimum, Maximum, and Gain fields. See Automatte Controls.
  3. Select the source clip.
  4. Select the destination in the Source Area or Record Area.

    The matte clip appears in the selected destination.

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    Original image

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    Matte generated with Min = 82, Max = 157

Automatte Controls

The Automatte controls are described as follows.

Minimum Specifies the minimum colour value for the matte. Any pixel with a luma value below the minimum value is set to black. The minimum can be set to any value between 0 and 255 in 8-bit mode, or between 0 and 4095 in 12-bit mode.

Maximum Specifies the maximum colour value for the matte. Any pixel with a luma value above the maximum is set to white. The maximum can be set to any value between 0 and 255 in 8-bit mode, or between 0 and 4095 in 12-bit mode.

GainBoosts the matte. Any pixel with a luma value between the minimum and maximum values is multiplied by the Gain and the new value is assigned to the resulting pixel. Using a low value for the Gain produces a soft matte with more grey levels. Using a high value produces a matte with fewer grey levels. Gain is expressed as a percentage value. The default value of 100% has no effect on the image since luma values are multiplied by 1.