Image Enhancements


You have your choice of these image enhancements:

Clipboard as CLUT
use the clipboard image as a color lookup table.

Spiff
enhances the intensity differences between the lighter and darker elements of the image.

Clahe
contrast limited adaptive histogram equalization. A good starting point is 2x2+128+3.

Dull
reduces the intensity differences between the lighter and darker elements of the image.

Contrast Stretch
improve the contrast in an image by `stretching' the range of intensity values. A good starting point is a 1% black and white point (e.g. 1%).

Equalize
perform histogram equalization on the image.

Normalize
transform image to span the full range of color values.

Negate
replace very pixel with its complementary color (white becomes black, yellow becomes blue, etc.).

Hue
vary the percent hue of the image (0-200%).

Saturation
vary the percent saturation of the image (0-200%).

Brightness
vary the percent brightness of the image. Reasonable values extend from 50 (darker) to 150 (brighter).

Gamma
level of gamma correction. The same color image displayed on two different workstations may look different due to differences in the display monitor. Use gamma correction to adjust for this color difference. Reasonable values extend from 0.8 to 2.3. You can apply separate gamma values to the red, green, and blue channels of the image with a gamma value list delineated with slashes (e.g. 1.7/2.3/1.2).

Level
adjust the level of image contrast. Give three point values delineated with commas: black, white, and mid (e.g. 10%,90%,1.0). The white and black points range from 0 to 100% and mid ranges from 0 to 10.

Linear Stretch
linear with saturation stretch. Give two point values delineated with commas: black, and white (e.g. 10,90%). The white and black points range from 0 to 100%.
Sigmoidal Contrast
sigmoidal non-lineraity contrast control. Give two values contrast and midpoint. Increase the contrast of the image using a sigmoidal transfer function without saturating highlights or shadows. Contrast indicates how much to increase the contrast (0 is none; 3 is typical; 20 is a lot); mid-point indicates where midtones fall in the resultant image (0 is white; 50% is middle-gray; 100% is black). A good starting point is 3x50%.