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97
votes
3answers
12k views

Recovering data points from an image

Unfortunately, some data can only be obtained in picture form (Japanese publications anyone?). Since this cannot be worked with, it has to be converted to a dataset that can; I was wondering whether ...
48
votes
7answers
3k views

Character edge finding

The following line of code finds the edge of a character: ...
77
votes
4answers
42k views

How to create a new “person curve”?

Wolfram|Alpha has a whole collection¹ of parametric curves that create images of famous people. To see them, enter WolframAlpha["person curve"] into a Mathematica ...
48
votes
5answers
9k views

How can I extract data points from a black and white image?

Consider the following graph (source): Is there any way to extract the data points from this image in a semi-automatic way? I have seen, and tried the methods suggested in this question, but they did ...
30
votes
4answers
3k views

How to extrude a 3D image from a binary 2D image

I'm trying to extrude a nice 3D form from the 2D binary image below using the code posted, but I haven't had any luck in figuring out the error that's keeping ...
84
votes
9answers
17k views

How to make an inkblot?

How to effectively create a polygon that looks like a realistic inkblot? So far, I could come up with this (borrowing from Ed Pegg Jr.'s Rorschach demonstration): ...
58
votes
2answers
3k views

How can I add drop shadows and specular highlights to 2D graphics?

I thought I'd share some code in the form of a self-answered question, but other answers are of course welcome. Drop shadows are a familiar visual effect, giving the impression of a graphical element ...
49
votes
4answers
4k views

Mollweide maps in Mathematica

Context In my field of research, many people use the following package: healpix (for Hierarchical Equal Area isoLatitude Pixelization) which has been ported to a few different languages (F90, C,C++, ...
33
votes
5answers
2k views

Create magnified call-out loupe effect on image

I'm trying to create a Mathematica Manipulate that generates a graphical call-out using a 'loupe'-style or magnifying glass enlarger - a possible solution is shown ...
14
votes
1answer
6k views

Image Processing: Finding Orientation and Position of Symmetry Axes

Background I'm currently toying with Principles of Design by Charlotte Jirousek in order to learn some basics of image processing. As main principals she suggests Balance, Proportion, Rhythm, ...
31
votes
3answers
2k views

How to detect crosses and circles in 60x60 raster images?

I have hand-written 60 pixel times 60 pixel squares. I need to detect whether they are empty, x or circle. TextRecognize function fails. Is there some other function to process this kind of raster ...
47
votes
2answers
2k views

Generating stippled (Penrose-style) drawings of surfaces

In The Road to Reality there are plots of surfaces that use a variable density of dots to suggest curvature. You can see some examples here and here. I suppose they've been drawn by Penrose, but to ...
26
votes
3answers
3k views

Finding a function that fits the shape of an image

How can I find a function that fits the given shape of an image? Or instead extract a point set from the shape and then find an interpolating function fits the shape. An example image is attached.
18
votes
2answers
503 views

Creating graph out of particles images

I have recently started learning how to use Mathematica's brilliant image processing tools, and the image I've taken as first example is the following (source): So far I've tried to first use ...
17
votes
4answers
11k views

Saving high-quality graphics through commands

Say I make and display a graph in a Mathematica notebook: graph = CompleteGraph[100] If I drag the corner of the graph to increase its size, and then save it to ...
5
votes
2answers
1k views

Color mixing or blend

Color mixing seems not only one type. Here is RGB_color_model I wrote this one: ...
7
votes
3answers
833 views

Opacity and overlapping multiple polygons

Let's say I have 100 polygons that are all different but most of them overlap. All I want to do is to draw/plot them in one single graphic with linearly adding gray values; i.e., a point with ...
7
votes
2answers
970 views

Fit an image within a Rectangle [] in Graphics

Based on the following Code (yet the white text in the image is added with PPT), I would like to have an image fit within one of the rectangle. For Example the image from there : http://...
43
votes
1answer
14k views

How can I draw a Homer with epicycloids? [duplicate]

You may have seen this video: https://www.youtube.com/watch?v=QVuU2YCwHjw. How does this work, and how to do it with Mathematica?
34
votes
4answers
3k views

How to make a stereogram in Mathematica?

Given a background and a pattern jpg files, is there a quick and easy way to produce a stereogram by using Mathematica? The following picture was produced from Photoshop, spent about half an hour. ...
27
votes
1answer
4k views

Vectorizing an image like “Trace Bitmap” in Inkscape

Lately, we had a nice question about artistic image vectorization which got very nice answers. As Szabolcs pointed out himself Since "true" vectorization performed by various specialized software ...
20
votes
3answers
3k views

Finding the centroid of a disk in an image

I got about 100 images of the sun and have to find the centre of the star in the images. I have binarized the images and used ComponentMeasurementsto find the ...
14
votes
2answers
424 views

How to retouch (smart fill) photo image?

Can the program proposed by Alexei Boulbitch at the post of Custom arrow shaft be adapted to retouch an image in setting a mask arround the part one desires to disapear? This is only a suggestion, ...
12
votes
2answers
3k views

Overlapping accurately Images and Graphics (without loss of resolution)

Context In a previous post, I learned how to produce these kind of plots, which are of interest in astrophysics and geophysics. I am now interested in combining them. Attempt For this purpose, @...
2
votes
1answer
440 views

How to make a big image/dashboard containing various data-graph

I want to make and image/dashborad (to export to PDF) with many VERTICAL bullet graphs gauges. And I can´t make it, in a automatic way. In general, the questions are: QUESTION 1: How to make a ...
5
votes
3answers
699 views

Tile image on specific location without space between them [duplicate]

Possible Duplicate: How to combine images with the same dimensions in a grid? I would like to arrange images without any space between their edges as each piece is made to connect with others. ...
0
votes
1answer
217 views

TextRecognize with crosses, circles and spaces results into oddities, why?

I am investigating this answer here about detecting crosses and circles with TextRecognize. I tried to solve this problem here by directly using the builtin command TextRecognize but it does not work ...
34
votes
1answer
1k views

Drawing Clifford Attractors in Mathematica

I came upon the "Clifford Attractor" today, which are equations of the form: $$x_{n+1}=\sin(a\ y_n) + c \cos(x_n)$$ $$y_{n+1}=\sin(b\ x_n) + d \cos(y_n)$$ They create some incredible images by ...
18
votes
2answers
1k views

How to measure segment length and branch angle

I am trying to measure segment length and branch angle or bifurcation angle between each pair of segments. My image after thinning looks like this: ...
3
votes
2answers
741 views

How to copy Coordinates of “Get Coordinates” in Figure?

I am trying to reproduce the answer here about Recovering data points from an image. I click the figure and press "Get Coordinates". I would like to copy the four coordinates by CTRL-C and then paste ...
13
votes
1answer
1k views

How to make a Nebulabrot?

A Nebulabrot is a generalization of the Buddhabrot, a fractal rendering technique related to the Mandelbrot set that sort of looks like a meditating buddha. The Buddhabrot rendering technique was ...
15
votes
4answers
519 views

How to separate paths from the output of EdgeDetect?

I have been trying to find a way to separate the various closed paths that can be output by EdgeDetect. For example, taking the output of: ...
8
votes
1answer
940 views

How to render a 3D tubular graphics from a 2D image path

Question: Is it possible to create a tubular 3D image like Extruding along a path using "Tube" function in mathematica for following images? Image (1) Image (2) Thanks I have been playing ...
5
votes
1answer
977 views

Circular crop: extract non rectangular parts of an image

I want to extract a part of an image. For example, let's start with something like the following image: I would like to apply some image processing to get this result: I have tried to manipulate <...
8
votes
2answers
391 views

Branching points detection in processed image

I want to get the branching coordinates from a computer-generated image like this one: After SkeletonTransform and Pruning, I ...
4
votes
2answers
701 views

Recognize simple shapes in an image and color them randomly?

I have an image of polygons built from a polar function (see below). I'd like to color each triangle or quadrilateral a random color. Firstly, I'm not sure how to separate the simple shapes. ...
2
votes
3answers
484 views

Visual superposition of two images

In a previous question Karsten 7. proposed an elegant image-manipulation solution on how to overlay two images. However in the following case the method does not properly work and needs refinement. ...
12
votes
1answer
491 views

Converting image into graphics

I have a black-white image, but it is rather blurry so I was thinking of converting it into vector graphics so I could do some coloring. This is the image: ...
6
votes
2answers
1k views

Image with grid lines

I have an image of a certain size. img = Image[source, ImageSize -> escala]; I want to add a grid with a scale (0 to maxX from left to right and 0 to maxY ...
2
votes
3answers
1k views

Calculate pixel intensity in two regions

I am just beginning to learn about image processing. I would like to know 1) How to show an original image with a visible mask of an arbitrary shape? 2) how to calculate the pixel intensities in the ...
6
votes
2answers
574 views

How do I transform a rasterized graphic's coordinates back to its original ListPlot data coordinates?

From this question I successfully made an elliptical fit for my data. However, when I try and collect the datapoints within the ellipse via this question the coordinates of my ellipse correspond to an ...
3
votes
2answers
287 views

Using high RasterSize or ImageResolution changes contour pattern

I found that the detailed contour pattern will be altered if we Rasterize the original graphics using high RasterSize or ...
3
votes
1answer
511 views

How to highlight image edge with spline/bezier when mouse moved over?

It is known that EdgeDetect can find image edges in an image. Suppose the image edges consists of sets of lines. Can the detected edge line near the mouse pointer be highlighted as spline/bezier when ...
2
votes
0answers
162 views

How to extract data points from an image of a log log plot? [duplicate]

I have a picture of a log-log plot, taken from a paper and I want to extract the data points so I will be able to plot them again along with results of my own solution. I would appreciate your help. ...
1
vote
1answer
318 views

Extract data from an image of a density plot?

I have a density plot in image form and would like to extract the data points from it. How would I go about using Mathematica to accomplish this? My ideal output ...