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Doric Swain
10-22-1997, 01:11 AM
At 04:57 PM 22/10/97 +1000, Jeff wrote:

>Has anyone ever had to digitise old hard-copy from a chart recorder ?
>A colleague would like to do just that, and is after any suggestions.

I have used and registered Digitize, shareware (US$50) which uses a scanned
image of the hard copy, from

Dr. Y. Danon
50 Hagilad St.
Arad 89034
ISRAEL
(danony@rpi.edu)

and find it does as good a job as you could reasonably expect. It has a
feature that automatically digitises a line - really efficient. The quality
of the final data will depend on the quality of the original paper data,
the quality of the scanned image, and the signal to noise ratio in the
original analogue signal. Once digitised, I have still needed to manipulate
the data in a spreadsheet.

You would find Digitize, and probably the freeware equivelant, Windig, on
most big shareware Web sites.
>
>Is the result of sufficient quality to do a FFT ?

Depending on the above criteria, and what resolution you're expecting in
the FFT, yes.

Doric Swain.
O__
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