# Tagged Questions

Questions on the image processing capabilities implemented in Mathematica.

3answers
366 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 ...
3answers
145 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 ...
3answers
173 views

### Coloring image components according to their area

I have a rasterized image img that is created by this code: ...
0answers
66 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: ...
1answer
206 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 ...
1answer
302 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 ...
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 ...
0answers
84 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 ...
2answers
256 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 ...
1answer
241 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 ...
1answer
222 views

### Smoothen the curve found by EdgeDetect

It seems that curves found by EdgeDetect always persist $C^{0}$ continuity only. Consider the following example: ...
1answer
241 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 ...
1answer
94 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: ...
1answer
280 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 ...
0answers
83 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 ...
0answers
124 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 ...
1answer
204 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.
1answer
56 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 ...
1answer
106 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 ...
0answers
24 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
1answer
239 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 ...
2answers
293 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 ...
0answers
151 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 ...
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 ...
1answer
264 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 ...
1answer
281 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 ...
1answer
165 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 ...
5answers
501 views

### Remove static objects from an image sequence

Is it possible to remove static objects/pixels from a sequence of images? Lets say I have a black square in the middle of my white picture (white background) and a black circle is orbiting around it. ...
0answers
289 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 ...) ...
2answers
150 views

### Image smoothing with own smoothing function

I have thousands images similar to the following one: This image was produced with the following color table: ...
1answer
164 views

### Better way to binarize an image

I have an image: pic = Import[ "http://note.youdao.com/yws/public/resource/\ 2c5a562224240edcf1631fcd39810f56/55FA538207424C0A98AB548724994AE1"] that I ...
2answers
615 views

### Trainable WEKA segmentation of images

Is there a Mathematica equivalent of Trainable WEKA Segmentation as implemented in Fiji, the image processing software? A Google search did not return any relevant links. I attach the original image ...
1answer
695 views

### Calculation of 2D FFT for an image

I am trying to obtain 2D FFT of an image. From the 2D FFT, I wish to calculate the amplitude of the FFT averaged over a circle vs the distance in pixels by varying the radius of the pixels which is ...
4answers
907 views

### Finding number of pixels with certain RGB color in an image

I have the following image: To determine the number of black pixels (nBlackPixels) I use: ...
0answers
110 views

### Identify and measure single bubble radius in series of images (TIFF)

I aim to make use of Mathematica's image processing capabilities to measure the radius of bubbles in consecutive images taken with a high-speed camera. After searching through this website I have ...
2answers
798 views

### How to fill the space outside of an image after rotating it

I want to rotate this image by -50 degrees, and then fill up the black space around the rotated image with a bluish color. I can't find any documentation/answers that suggest how to do it. (Sorry ...
3answers
425 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 ...
2answers
165 views

### Speed up image coloring with ReplaceImageValue

I have about 200000 rgb-images of such format (2160*577 pixels): I want to colorize in each image some parts in white color: ...
0answers
226 views

### adaptive histogram equalization

There is an interesting algorithm called contrast enhanced adaptive histogram equalization that does histogram equalization on small segments of an image (and then pastes them back together). I know ...
2answers
496 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 ...
0answers
39 views

### Using an arbitrary area bounded by lines for PDEs?

I have a set of lines I pulled from an image that make a closed loop, pretend it's a unit square for reference. Is there a way to use such an arbitrary region for solving PDEs, and is there a way to ...
0answers
121 views

### Extract peaks from image

EDIT: I've managed to solve the problem by using "Get Coordinates" on a couple of points and then figuring out the affine mapping by using the values they're supposed to be at, and applying that ...
1answer
166 views

### What kind of algorithm can be used to map image coordinates to cylinder coordinates

I plan to flatten an images on curved surface(eg: jar or door knob) and I found a pretty good post which helps me a lot :)(link below). However, I still confuse on how to map image coordinate to ...
0answers
78 views

### Pulling the boundaries from a Solidworks Profile in Mathematica

I'm currently trying to take a 2d profile generated in SolidWorks and use mathematica to analyze it. I need to pull lines that represent the boundaries of the shape from an image of the shape. . My ...
3answers
539 views

### How to speed up Colorize

I have a list of about 500 images similar to the following: A = Import["http://i.stack.imgur.com/1bV4O.png"] ...
0answers
95 views

### ImageData to Image to ImageData, in LABColor [closed]

Given an $m\times n$ image $G1$, I'm trying to: Extract the $mn$ pixels of $G1$ as an $n\times m$ matrix $M1$ of triples, where each triple represents the color in LAB space. Turn $M1$ into an \$m\...
1answer
292 views

### Using ImageIdentify

How long does it take ImageIdentify to give an answer for one image? Also, I suppose using it requires an Internet connection with Wolfram servers. Is that correct?
1answer
352 views

### Compute a hessian matrix on a image?

Is it possible for Mathmatica to load a gray image and apply a hessian matrix on it?... It used image processing to find good features.
0answers
143 views

### Mapping Images in Parisian metro stations

One particular aspect of some Parisian metro stations is that stations' walls are curved, even in the sides where one would place advertising posters. Here is a picture of one such station: I was ...
0answers
125 views

### How to import all the images in a folder? [closed]

the source code is ...