Retinex (java & class files) This
plugin is a modified implementation of the Retinex filter
from the GIMP pacakge. Retinex filtering is based on Land's theory of image
perception, proposed to explain the perceived colour constancy
of objects under varying illumination conditions. Several approaches
exist to implement the retinex principles, among these the multiscale retinex with
colour restoration algorithm (MSRCR)
combines colour constancy with
local contrast enhancement so images are rendered similarly to how
human vision is believed to operate. Unfortunately, there appears to be a
the GIMP filter, specifically in the implementation of the linear
Gaussian filter. The bug was avoided here by replacing the original
linear Gaussian filter routine with the built-in
filter of ImageJ.
The ImageJ plugin was written by Francisco Jiménez Hernández
(UAEMex) jimenezf at fi.uaemex.mx during a research visit
to Birmingham University, School of Dentistry.
Copy the java and class fles to the /plugins folder or subfolder and run Help>Refresh Menus.
A new Retinex entry should appear in the plugins menu or submenu. In
Fiji, you might need to move the *.java file somewhere else.
The plugin expects an RGB image or stack.
specifies distribution of the Gaussian blurring kernel sizes for Scale division values > 2:
Uniform tends to treat all image intensities similarly,
Low enhances dark
regions of the image,
High enhances the bright regions of the image.
Scale specifies the depth of the retinex effect.
Scale division specifies the number of iterations of the
multiscale filter. Values larger than 2 exploit the "multiscale" nature
of the algorithm.
Dynamic adjusts the colour of the result. Large values produce less saturated images..
Left: original histological image of human epithelium stained with haematoxylin and eosin. Right: image restored with retinex algorithm "low"
original image. Right:
image restored with retinex algorithm "uniform" setting. Note the
restoration of the colours despite the overall cyan tone of the
original image (courtesy of AD Walmsley) with dark shadows and bright areas. Right: image restored with retinex algorithm "low" setting. Note the shadowed regions become more visible.
Last updated on 19/Jul/2010.