SOFTWARE FOR IMAGE SEGMENTATION AND ANALYSIS
IN PATHOLOGY (ISAP).
VALUES MENU.
Copyright © 1994 G. William Moore, Geoffrey W. Moore,
Jules J. Berman, Lawrence A. Brown.
http://www.medparse.com/isapvalu.htm
U. S. Government Work, presented at the 1994 meeting
of the American Society of Clinical Pathology, Washington, DC.
Moore GW, Berman JJ, Moore GW, Brown LA.
Software for Image Segmentation and Analysis in Pathology (ISAP)
Am J Clin Pathol 102:538-539, 1994.
1. ISAP VALUES MENU.
VALUES submenu: This is a submenu of the ANALYSIS menu.
If there is an OPEN IMAGE (FILE menu) on the screen,
and a particle has been BLOCK SELECTed (IMAGE menu),
then the VALUES submenu of the ANALYSIS menu displays
particle area (AREA), sum of gray values in the particle
(GRAYSUM), sum of optical densities in the particle
(DENSESUM), average optical density (DENSEAVG),
standard deviation of optical density (DENSESTDV),
least standard error divider (DIVIDER),
average diameter of the particle (AVGDIAM),
greatest diameter (MAXDIAM), least diameter (MINDIAM),
elliptical eccentricity (ECCENT), center-of-gravity
x-axis (XCENTER) and y-axis (YCENTER), particle
contour (CONTOUR), fractal dimension (FRACTAL),
and perimeter (PERIMETER).
The AREA is the number of pixels inside the particle.
GRAYSUM is the sum of pixel-GRAY_VALUEs inside the particle.
From each GRAY_VALUE, the OPTICAL_DENSITY is calculated by
the formula: OPTICAL_DENSITY=LOG10(255/(255-GRAY_VALUE)),
with OPTICAL_DENSITY equal zero if GRAY_VALUE equals 255.
The DENSESUM is the sum of OPTICAL_DENSITY values
inside the particle. DENSEAVG equals DENSESUM/AREA,
and is designated with a BLUE LINE on the HISTOGRAM.
DENSESTDV is the standard deviation of OPTICAL_DENSITY
values inside the particle.
If the x-axis of the HISTOGRAM
is divided at all points, and a Student t pooled standard
error is calculated for the left and right histograms,
then the minimum pooled standard error is obtained
at the DIVIDER, and is designated with a YELLOW LINE
on the HISTOGRAM.
The MAXDIAM for the particle is
the (Euclidean) distance between the two most distant
edge-points. If the particle is assumed to be an ellipse,
then: AREA = (pi/4) * MAXDIAM * MINDIAM, and
ECCENT = MAXDIAM/MINDIAM. If the particle is assumed
to be a circle, then: AREA = (pi/4) * AVGDIAM * AVGDIAM.
PERIMETER is the sum of edge-points of the particle.
The particle CONTOUR equals PERIMETER/sqrt(AREA).
For a perfect circle, the CONTOUR assumes a minimum value
of 3.54.
The FRACTAL DIMENSION, s, of a particle is a
quantitative measure of complexity along the particle edge.
s = 1 + lim(d->0) log2((PERIMETER at 2*d)/(PERIMETER at d)),
for GRIDSIZE=d. All the enclosures of classical plane
geometry (circle, rectangle, polygon) have a smooth edge,
for which s approaches 1 as GRIDSIZE approaches 0. ISAP(c)
calculates s for GRIDSIZE=1 pixel.
Last Updated: January 23, 2003, by G. William Moore, MD, PhD.