op_contrast

Adjust contrast. Adjusts the image contrast by increasing the brightness of pixels with more than 50% brightness, and reducing the brightness of pixels with less than 50% brightness.

op_contrast=adj

adj

Contrast adjustment in percent (-100…100 int).

Properties

Layer command. Applies to the current layer or to the composite image if layer=comp. Ignored by effect layers.

Default

op_contrast=0, for no change in contrast. CMYK images or layers are converted to RGB before the operation is applied.

Example

Decrease the contrast and sharpness of a higher quality image layer to visually match it to a low-quality background photo:

&op_blur=3&op_contrast=-12&

A future release may use the median brightness of the image rather than a fixed 50% brightness.