Color range conversion

Changes the range and distribution of values for all pixels

Documentation

Algorithms

adaptive histogram

Improves contrast by stretching and equalizing the histogramin a sliding window over the image

bins:

Number of bins in computed histogram (default 256)

adaptive kernel size:

Size of the sliding window. Must evenly divide both image width and height.

sigma:

Clipping limit (normalized between 0 and 1). Higher values give more contrast. (default 1.0)

More info: http://scikit-image.org/docs/0.13.x/api/skimage.exposure.html#skimage.exposure.equalize_adapthist

gamma correction

Applies the correction: Vout = scale Vin^gamma Processes each channel separately

scale:

Constant scale factor applied after gamma correction

gamma:

Gamma factor applied to image. <1 increases intensities of mid-tones, >1 decreases intensities of mid-tones

More info: http://scikit-image.org/docs/0.13.x/api/skimage.exposure.html#skimage.exposure.adjust_gamma

histogram equalization

Improves contrast by stretching and equalizing the histogram

bins:

Number of bins in computed histogram (default 256)

More info: http://scikit-image.org/docs/0.13.x/api/skimage.exposure.html#skimage.exposure.equalize_hist

log correction

Applies the correction: Vout = scale log(1 + Vin) Processes each channel separately

scale:

Constant scale factor applied after gamma correction

inverse:

Perform inverse log-correction instead (default false): Vout = scale (2^Vin - 1)

More info: http://scikit-image.org/docs/0.13.x/api/skimage.exposure.html#skimage.exposure.adjust_log

sigmoid

Performs Sigmoid correction on input image. Also known as contrast adjustment. Vout = 1/(1+exp(gain*(cutoff-Vin))) Processes each channel separately

inverse:

Perform negative sigmoid correction instead (default false)

cutoff:

Shifts the characteristic curve for the sigmoid horizontally(default 0.5)

gain:

Gain of sigmoid, affects rise time of curve (default 10.0)

More info: http://scikit-image.org/docs/0.13.x/api/skimage.exposure.html#skimage.exposure.adjust_sigmoid

Definition

Input ports

source image

source image to filter

Output ports

result image

result after filtering

Configuration

adaptive kernel size (adaptive kernel size)

(no description)

Algorithm (algorithm)

(no description)

bins (bins)

(no description)

cutoff (cutoff)

(no description)

gain (gain)

(no description)

gamma (gamma)

(no description)

inverse (inverse)

(no description)

scale (scale)

(no description)

sigma (sigma)

(no description)

Implementation

class node_colors.ColorRangeConversion