Questions on the image processing capabilities implemented in Mathematica.

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0
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1answer
21 views

Remove color artifacts in overlay of several `Graphics` objects?

I am trying to create an animation with a graphic of an arm that can bend at the elbow. For this purpose I created the following two images: hand1 and hand2. I load the images with ...
6
votes
3answers
118 views

Which values did ImageAdjust choose?

I have a picture obtained from a camera in an experiment. It's a .dat file, contains only numbers. I can re-create the image by importing it as data and using the ...
15
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2answers
1k views

Scraping High-Res images from the MoMA and the Van Gogh Museum websites

Many art websites allow the user to zoom into an image to see it at high resolution by using image tiles. It is great on the website, but presents problems if one wishes to compile a complete high ...
6
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1answer
48 views

ImageAdjust Documentation issues

A recent thread raised several concerns regarding the Documentation page for ImageAdjust. The first issue is related to the first statement under the ...
14
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2answers
467 views

How to detect loops in a vector field?

Given a vector field and I'd like to detect if there are streamlines in closed patterns. For example, if the input is a vector field like this: ...
7
votes
3answers
297 views

Coloured image transformation in pointillism

I would like to transform an image (a photo for example) into a set of single colour circles with fixed but adjustable diameter (bigger than the pixel size), into a kind of pointillism. The number of ...
3
votes
2answers
94 views

Coloring image components according to their area

I have a rasterized image img that is created by this code: ...
5
votes
1answer
119 views

Image analysis: Gravel Sieve

In this link: http://broadwaysand.com/?page_id=165, you can find different gravel pictures. A quarter dollar coin gives the scale, because its diameter is 0.955 inches (24.26 mm) I want to get the ...
1
vote
0answers
47 views

Create set of data from vector curve [closed]

I need exactly what is written in the title. Suppose we have some curve plotted: p = Plot[Sin[x],{x,0,2pi}] now we save that as vector graphics: ...
5
votes
1answer
119 views

How to calculate the mean of images?

In practice, subtracting the mean image from a dataset significantly improves classification accuracies. I thought there would be a ImageMean[] function but can't ...
13
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3answers
3k views

Composing an image with a plot

I'm trying to illustrate the solutions to a textbook problem dealing with quadratic functions. This will involve plotting a quadratic and overlaying the plot and the image. Here is the textbook ...
2
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0answers
37 views

How to do text recognition in a language that doesn't use the roman alphabet [closed]

I am trying to reconize a single letter or character from a non-roman character set by edge detection. I want to extract single characters from a text image. When I identify that letter or character I ...
5
votes
1answer
177 views

Calculate dual graph of planar Graphics map

This diagram from a Wikipedia article illustrates what I hope to accomplish in Mathematica: I have a planar map in Graphics format. Here are two very simple ...
4
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0answers
109 views

How to make distance transform invariant to scale?

I am trying to use a distance transform as a descriptor to encode silhouettes in order to do a shape recognition task. It is clear that distance transform distribution is invariant under rotation and ...
14
votes
3answers
893 views

Processing a circular rainbow in an image

While on a cross-country flight, I observed what looked like a complete circular rainbow, visible against the backdrop of clouds. I took several photos thru the window with my small Nikon camera, one ...
2
votes
1answer
140 views

How can I capture a rectangular area from an image?

I am looking for a method to extract rectangular areas from an image. The image is divided up into rectangular problem spaces like the image shown below. Each numbered problem is given with some text ...
4
votes
1answer
118 views

How to transform an image into a probability density function?

I'd like to use the Metropolis algorithm to randomly generate points with density according to the brightness of an image. I just need to transform a binary image into a pdf function to use this ...
21
votes
3answers
1k 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.
10
votes
3answers
329 views

Best method to find variation in width along the image of a slit?

EDIT: Solutions by @Alexey Popkov and @Vitaliy Kaurov are very intuitive and both can be used to find a solution for the task. I have a slit of 15-18 microns by 1 mm projected with magnified 4X onto ...
0
votes
1answer
278 views

How to apply a conformal map to a jpg (or other image) [duplicate]

I would like to apply a conformal map to a jpg. For example, the map $z\mapsto z^2$ to this image: http://thumbs3.ebaystatic.com/d/l225/m/mGyeriV7l-YArkeBd9oMUng.jpg Any help on how to do this?
6
votes
1answer
140 views

Smoothen the curve found by EdgeDetect

It seems that curves found by EdgeDetect always persist $C^{0}$ continuity only. Consider the following example: ...
16
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2answers
1k views

False colour SEM image with Mathematica

I have an image of gold electrodes on a flat substrate obtained with a scanning electron microscope. I would like to colour in all the gold electrodes and particles that appear in the center of the ...
8
votes
1answer
152 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 ...
7
votes
1answer
159 views

Is there a way to characterize a winding object in an image?

I have produced this image by applying a Gaussian image substraction, Binarize, Colornegate, and ...
1
vote
0answers
91 views

Understanding the use of GradientOrientationFilter to achieve a “brushed” effect

I'm trying to recreate in Javascript a piece of code that appeared here on Mathematica, specifically in this answer. The user Simon Woods suggested an amazingly efficient way of drawing lines over ...
2
votes
1answer
83 views

ColorReplace does not work

I want to do - seemingly - simply image processing. I want to replace all blue pixels with white pixels. The obvious command would be: ...
1
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0answers
54 views

How to segment letters and text blobs?

This new article from Google research describes how their Translate app preprocesses an image on a phone before applying convnets: It needs to weed out background objects like trees or cars, and ...
3
votes
0answers
42 views

Tracking features where ImageFeatureTrack finds none?

How is it possible to track common features in the following sequence of images (e.g. holes or corner points along the top margin), ? I have had no luck with ...
1
vote
1answer
170 views

How to increase the thickness of the edge in a random image

This is a Voronoi Diagram. I really want to know how to change the thickness of the "wall" of each V-cell, in another words, the thickness of the edge in this diagram.
8
votes
3answers
416 views

Radon function result's repeatability

Bug introduced in 9.0.0 and fixed in 9.0.1 I want to get a Hough transform of some edged image. When I compare the same transformation on the same image I got different results. ...
1
vote
1answer
37 views

How to select components selected via SelectComponents?

I have selected the components of a "reduced" (dilated, thinned) image, now I need to go back to the original image and find the coordinates of the components I have found. My code currently does ...
5
votes
1answer
84 views

How to create a MorphologicalGraph from MorphologicalBranchPoints

I want to select the morphological branch points of a thinned image to create a MorphologicalGraph like the one obtained by Pruning. I want to avoid the pruning step. How can I delete from the ...
17
votes
3answers
1k views

How can I efficiently “remap” an image?

Many image processing libraries like OpenCV, Intel Performance Primitives or Octave have a useful function called "remap", that takes an image, an array with X coordinates and an array with Y ...
30
votes
2answers
1k views

How do I remove grid from this photo?

I found this cat a month ago, and I'm not his owners' friend so the mosquito grid was the inevitable problem. I would like to post-process this photo to get rid of it, but I don't know exactly how ...
11
votes
2answers
200 views

Extract bathymetry data from a map

Thanks everybody for edit and recommend. Here is a clearer version of my question. I have a map that shows bathymetry of a lake with legend showing depth relative to a range of color. The map ...
-2
votes
1answer
165 views

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 ...
0
votes
0answers
22 views

marking spontaneous in an Image and collect coordinates [duplicate]

How to mark spontaneous in an image and collect all the positions of marking. also then any example will be great aon land mark based registration Thanks
10
votes
1answer
497 views

How to find a specific color in one picture?

In a picture, there are many different colors. How can I just want to find the position of one color. In the following picture, if I would like to find the coordinates of the position of blue, how can ...
6
votes
1answer
208 views

Mathematica ignores image orientation

I have a bunch of mixed images, some portrait orientation, some landscape, which I want to be processed by Mathematica. When I Import them Mathematica handles them ...
30
votes
1answer
1k views

May the Fourth be with you

Happy Star Wars day. I was playing around with the image manipulation functions in Mathematica in an attempt to recreate the Star Wars crawl. There's an HTML/CSS implementation which is in my ...
1
vote
0answers
113 views

Alternatives to Mathematica that are not computer algebra systems [closed]

Are there alternatives to Mathematica that are not computer algebra systems? I know there have been questions on this, but I am focusing on oprn source projects and instead of focusing on computer ...
17
votes
2answers
296 views

Reconstruction of interrupted paths in images

I want to reconstruct paths in images and have already implemented a working method in Mathematica. On the left side you can see an image with interrupted paths and on the right side the reconstructed ...
23
votes
2answers
1k views

How can I create a glass distortion effect in an image?

I'd like to overlay a glass jar onto an image with realistic light bending. Can anyone think of a way to automate this effect? Perhaps this can be done with the raytracing package Rayica / Optica? ...
19
votes
3answers
615 views

White balance correction with Mathematica

Does Mathematica include a function to correct the white balance of an image? ImageAdjust would seem to be the first go-to choice, but I haven't found a way to ...
18
votes
2answers
355 views

Get measurements of touching particles in an image

I have a picture of glass spheres. I want to calculate different properties of these spheres such as circularity, size, and count. I have managed to fill the white centers of the particles to ...
9
votes
2answers
978 views

How to transform a 3D image by an affine transformation matrix

I have a question concerning Image Processing: I have a stack of images, which I can compose to a 3D image using Image3D. Additionally I have a 4x4 affine transformation matrix. I would like to ...
6
votes
0answers
248 views

Visualization of traces of moving objects

An example movie which is made with the listed mathematica code below shows traces of moving objects: https://youtu.be/8jN2uuSHCEg (Melting ...) http://youtu.be/5ET62846C-I (Crystallisation ...) ...
4
votes
1answer
90 views

Optimal Binarize value for counting experiment

I am currently working on a physics experiment where I count particles. I have looked at and used a bit of code from the following sources: Cell counting from an image file and Count Elements in Image ...
5
votes
1answer
340 views

Volumetric Rendering of cylinder symmetric radial image

I would like to render a cylinder symmetric radial cross-section with Image3D. As an example one could use the propagation of a Bessel Beam through a Lens: Here the cylinder axis is the bottom of ...
4
votes
1answer
91 views

Averaging over a circle from FFT to plot the amplitude vs wavelength

I am trying to calculate the amplitude of FFT vs wavelength for some experiments. I had put a question here previously on how to compute the FFT of an image. Thanks to everyone who provided the ...