||Measurement of Boundaries Using a Digitizer Tablet.
Mercer, R. R. ;
Randell, S. H. ;
Young, S. L. ;
||Duke Univ. Medical Center, Durham, NC.;Health Effects Research Lab., Research Triangle Park, NC. Environmental Toxicology Div.
Computer graphics ;
Analog to digital converters ;
Error analysis ;
Mathematical models ;
||Most EPA libraries have a fiche copy filed under the call number shown. Check with individual libraries about paper copy.
The perimeter is the most error prone of the primary measurements (length, perimeter and area) made when using a device such as a digitizer tablet to trace profiles on micrographs. To allow for minimization of the error an expression is developed relating the error in the perimeter to the digitizer resolution plus other errors in the entry process. The predictions of the expression are shown to be in good agreement with the results of computer simulation of the tracing process, as well as results from manual tracing using a digitizer tablet. The analysis of the digitizer entry process also provides a method by which an optimal choice of the sample spacing between digitizer coordinates can be made. (Copyright (c) 1990 The Royal Microscopical Society.)