Re: Converting a magnified image of a line to a single
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- Subject: [mg130577] Re: Converting a magnified image of a line to a single
- From: Matthias Odisio <matthias at wolfram.com>
- Date: Tue, 23 Apr 2013 00:04:04 -0400 (EDT)
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Dave, On 4/20/13 4:41 AM, Dave Waddell wrote: > 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 ImageValuePositions will give you the coordinates of the white pixels: In[21]:= ImageValuePositions[Image[IdentityMatrix[3], "Bit"], 1] Out[21]= {{0.5, 2.5}, {1.5, 1.5}, {2.5, 0.5}} Please note that ImageValuePositions does not sort the returned positions in any specific order. Matthias
- References:
- Converting a magnified image of a line to a single pixel smoothed
- From: Dave Waddell <dwwaddell@gmail.com>
- Re: Converting a magnified image of a line to a single pixel smoothed
- From: "Dave Waddell" <dwwaddell@gmail.com>
- Converting a magnified image of a line to a single pixel smoothed