# How to get the coordinates of points within an image?

How can I get the coordinates of an image, and make Mathematica draw the image from the coordinates found? I am interested in just the outlines of the regions.

Here is an example of the kinds of images I'd like to process.

• Coordinates refer to a point; your image is made up of a bunch of points. Now, which? Jul 13, 2015 at 18:31
• Is the skeleton you are looking for a cube with an S-shape on one of its sides? Jul 13, 2015 at 18:44
• Oh, you want the outline Jul 13, 2015 at 18:45
• You mean EdgeDetect? Jul 13, 2015 at 19:10
• If you look closely, there is a "W" and "S", that need Jul 13, 2015 at 20:41

## 1 Answer

Click on your figure. Then a set of graphics tools will appear beneath your figure. Use the Coordinates Tool. One by one, click on the corners of the region you seek. Then use the window below to Copy Coordinates. Here the ones I get for the front W face of your figure:

{{72.5, 507.5}, {70.5, 158.5}, {135.5, 140.5}, {136.5,
484.5}, {209.5, 459.5}, {208.5, 120.5}, {280.5,
98.5}, {282.5, 437.5}, {350.5, 425.5}, {347.5, 7.5}, {6.5,
108.5}, {7.5, 530.5}, {72.5, 507.5}}


Then merely plot them:

Graphics[{Blue,
Polygon@{{72.5, 507.5}, {70.5, 158.5}, {135.5,
140.5}, {136.5, 484.5}, {209.5, 459.5}, {208.5,
120.5}, {280.5, 98.5}, {282.5, 437.5}, {350.5,
425.5}, {347.5, 7.5}, {6.5, 108.5}, {7.5, 530.5}, {72.5,
507.5}}}]


Of course, you can repeat this for each face of your figure, for instance with the S:

If you just want the "skeleton" our outline, use Line instead of Polygon:

• yes, I needed something like this, thanks Jul 14, 2015 at 15:54
• Sorry, do not leave me the coordinates of WS, the you can write please Jul 14, 2015 at 20:31
• @juanmunoz Sorry, but I explained precisely how you could capture the points, gave you the points for the W, and I'm too busy to do more work for you. Jul 14, 2015 at 20:35
• sorry to bother, but nobody is born knowing, it may seem easy for some, but for others it is not so, just thanks for your help. Jul 14, 2015 at 20:57
• @juanmunoz Did you try to follow my explanation and directions in my solution? If so, where did you have problems? Jul 14, 2015 at 22:38