In article <1991Oct8.064744.1 at cc.utah.edu> eyring at cc.utah.edu writes:
>Digitizing ink graphs back into numerical data.
>>We need to be able to get the raw values of the data into numerical
>format so we can integrate the data into our flight simulator.
>>>Bob Witmer
>>eyring at cc.utah.edu
If you have a mac, 'NIH Image' (posted at many sites) has a clever
script (written it it's pascal-like macro language) for doing
exactly this. The script masks the image with a grid in order to break
the continuous curves (of data) into dots. Then the 'object [particle]
analyzer' routine gives the x,y coords of each 'dot', which is treated
as an object. Finally, a baseline is subtracted (to give the x,y axes)
and out falls the data. Since NIH Image can calibrate an image to real-
world dimensions, the data can be scaled to the right units automatically,
in many cases.
Image is avalable at a number of sites. ftp sumex-aim.stanford.edu
or ftp alw.nih.gov are two ways to find it!
Bob Straubinger
Pharmaceutics, SUNY Buffalo