Dear Confocalist:
 
Our software for contrast imaging and contrast segmentation is now
available on the web and proved very useful for fluorescence imaging by
 
      providing an easy tool for noise management
            as well as detail contrast enhancement
      provides quantitative contrast segmentation
      works on single channel graytone images (8-16 bit)
            as well as output color images (24-bit).
 
Free access to the software at URL
 
            http://panda.uchc.edu/htklaus/DHP-Img.html#Software
 
Our "differential contrast imaging" utilizes the hysteresis properties of
an image. The image hysteresis characterizes the "significance" of
intensity variations with a single intensity value that defines the
minimum significant contrast (reference below). For differential contrast
segmentation only two intensity values are used: show me contrasts which
are larger than 55 and smaller than 75.
 
The mathematical procedure of differential hysteresis processing (DHP) segments
all contrasts of that range and produces a truly continuous graytone image
of 8-bit (Ref.: MSA 1995, pp.642-643: Digital differential hysteresis image
processing displays what the microscope acquires but the eye can't see).
More over, the image will be "free" of spatial artifacts as well as
intensity artifacts (when compared to conventional differential contrast
enhancement procedures, see below) and thus maintain your microscope's
precision of data collection.
 
The "DHP differential contrast imaging" works as well in color with
reversed RGB-to-HSV conversion. Look at the neuron at:
 
        URL http://panda.uchc.edu/htklaus/Seeing.html#Confocal
 
The main advantage of contrast imaging is:
 
1.) DHP  "segments contrast" in an evenly way from the whole image and thus
is not directly affected by any particular local "intensity levels" (as in
intensity slicing, local neighborhood histogram adjustments, averaging of
selected intensity ranges or background adjustments). It can segment the
major noise components and thus present images with reduced noise and
enhanced detail contrast.
 
2.) DHP works on all images and you do not have to define anything other
than the particular contrast range you want to segment (visualize or
quantify), i.e., no background and bandwidth adjustment and selection from
"good" and "bad" processing results.
 
 
Differential hysteresis processing (DHP) for contrast imaging is an
approach that is principally different from other differential contrast
enhancement techniques as found in unsharp masking (using an averaged
background), OHO filter (using a median smoothed background) or SIS's
differential contrast enhancement DCE-filter (local histogram adjustment).
In contrast to the first two filters, the SIS filter especially distorts
the image contrasts since it "enhances" small contrasts depending on the
local intensity level. DHP uses the difference between any two hysteresis
images. Thus, DHP can sequentially segment any contrast from an image,
small as well as large, 8-bit as well as 16-bit. Each of the segmented
differential contrasts is imaged as a coherent contrast pattern image and
all contrast patterns are accumulative, i.e., you can segment an image into
it's contrast components (contrast patterns) and reassemble it again from
these contrast patterns into the original image, without any loss or
artifacts (advantage of mathematical data treatment). None of the
"differential contrast filters" does that. More details on the benefits of
DHP for digital imaging at:
 
        URL http://panda.uchc.edu/htklaus/Contrast.html
 
Best regards     Klaus
 
 
 
******************************************************************************
*  Klaus-Ruediger Peters, Ph.D.             :Molecular Imaging Laboratory    *
*  Director, Molecular Imaging Laboratgory  :   http://panda.uchc.edu/       *
*  Biomolecular Structure Analysis Center   :   htklaus/index.html           *
*  University of Connecticut Health Center  :                                *
*  263 Farmington Ave.                      :F r e e  Access to Differential *
*  Farmington, CT 06030-2017; U.S.A         :Contrast Software at            *
*  e-Mail: [log in to unmask]             :   http://panda.uchc.edu/       *
*  Tel: (860) 679-3977; Fax: (860) 679-1989 :   htklaus/DHP-Img.html#Software*
******************************************************************************