Edge recognition software

Paul Storch <paul.storch<-a t->mnhs< . >org> writes

>I just had an inquiry from a microanalyst at our state's Bureau of
>Criminal Apprehension (Minnesota's FBI crime labs) who asked me if I
>knew of a computer program that automatically does edge matching of
>fragments of glass and/or ceramics.

There is a whole host of raster to vector conversion programs that
may be useful for this. We recently bought Hitachi's Image Tracer
Professional which has a whole host of "line following routines'
which would probably be quite useful to Paul. Theseare ordinarily
used commercially to automatically digitize maps into things like
AutoCAD and various GIS programs. another nice one is CAD Overlay,
produced by Autodesk the maker of AutoCAD.

Some of this software is pretty expensive but there are some that
are not too pricey. I believe there are also shareware and freeware
programs that do this. The beauty of things like the Hitachi
software is that once you do it you have it in vector format and can
overlay it on images to proper scale and fun stuff like that.

I think a WEB search on "raster and vector" will bring up a whole
host of various softwares.

I'm not aware of anything [to do matching of fragments] like this
but it may exist. It would certainly be useful to conservators
working on ceramics and glass. I think it might not be a terribly
complicated thing to write a program for. If they can't find
anything they should consider approaching one of the companies that
does similar edge following algorithms. The edge following stuff
for raster/vector conversion is presumably aimed at tracing lines
and saving money and time on human digitizing using traditional
digitizing methods.  They want to take this one step further and do
some edge matching. There may be an industrial application for this
or it may even be a feature of some programs. If I hear anything
more I'll post. all the best,

Mitchell

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                  Conservation DistList Instance 11:56
                Distributed: Tuesday, December 23, 1997
                       Message Id: cdl-11-56-001
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