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Re: Converting a magnified image of a line to a single pixel smoothed

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  • Subject: [mg130539] Re: Converting a magnified image of a line to a single pixel smoothed
  • From: "Dave Waddell" <dwwaddell at gmail.com>
  • Date: Sat, 20 Apr 2013 05:41:29 -0400 (EDT)
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I tried converting the result image to a graph so that I could apply a
moving average and then fit a B-spline through it. As you can tell I'm new
to Mathematica:
data = ArrayRules@SparseArray@ImageData[result]
It was all downhill after that. Another nudge would be appreciated.
Thanks, Dave.

Dave,

On 4/17/13 1:30 AM, Dave Waddell wrote:
> I have a magnified image of a 0.1mm line here:
> http://www.d-a-v-e.org/images/Trace.jpg
> ... this converts with Binarize very well:
> http://www.d-a-v-e.org/images/Trace%20binary.jpg
> ... but what I would like to do is convert it to a single pixel wide
smoothed line running right up the middle. Any suggestions or pointers on
how to do this in Mathematica would be appreciated.
> Dave
> 

The sequence below seems like a good start.
The documentation for the functions should help you understand what is going
on in more details:

trace = Import["http://www.d-a-v-e.org/images/Trace.jpg";]

b = ColorNegate@Binarize[trace];
b2 = SelectComponents[b, "Area", -1];
b3 = FillingTransform@b2;
dt = ImageAdjust@DistanceTransform@b3;
result = ColorNegate@Image[WatershedComponents[dt], "Bit"];
HighlightImage[trace, result]


Matthias Odisio
Wolfram Research





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