User`s manual

Chapter 5: Analysis Tools
5-69
Example Of A Spot Density Data Window
If this window obscures a region of interest, resize and/or move it following Windows
®
conventions. Alternatively, close the data window by clicking in the checkbox next to
the HIDE DATA heading in the toolbox. An “X” appears in the box, indicating that this
option is selected. To re-display the data window, click in the checkbox again.
Data Definitions
# is the number assigned to each object on the image in the order in which they were
drawn. This object number is also shown in the corner of the object.
IDV is the sum of all the pixel values after background correction:
IDV = ∑ (each pixel value - BACK)
% is the percentage that each box, ellipse, or freehand drawing contributes to the total
density measured thus far, taking background correction into consideration. The sum of
the values in this column will be 100.
AREA is the size (in pixels) of the region enclosed by the box, ellipse, or freehand
drawing.
AVG is the average value (after background correction) of the pixels enclosed.
AVG = IDV ÷ AREA
BACK is the background value that will be subtracted from all the pixels in the object.
(See Calculating Background Values below for more information.)
Inverting the Data