# Tagged Questions

Questions on the image processing capabilities implemented in Mathematica.

754 views

### Failing to import an .eps file

I have an .eps file which was created using GLE. There is nothing wrong with the file, GS View can read it correctly. However, when I use Mathematica to read it using ...
254 views

### Image's pixels GPU colour classes splitting

How can I split in color classes, the pixels of an image that I load in Mathematica? I would an output like this: ...
54 views

### How can I manipulate a circular part of an image? [duplicate]

I want to a specific part of an image, while leaving the rest of the image unchanged: The part should be circular en the center and radius of the circle should be easily adjustable. So far I can only ...
904 views

### Detecting and correcting gradational brightness variations in a grayscale image

I am trying to quantify the proportions of various components in a greyscale image (backscattered electron image of a polished rock sample). Here is the original image: ...
2k views

### Measure length and diameter of objects in an image

I am new to Mathematica, and I am trying measure length and diameter of rectangular objects in an image. I wanted to fit rectangles in the objects, and then get the values. Can I do that with ...
1k views

### Generating x,y coordinates for an edge detection

I'd like to be able to process a number of graphics that have edge contours and output a list of $x$, $y$ coordinates to be used for generating a spline in another program, or in Mathematica, to make ...
308 views

### in search for mathematica function similar to imagesc in matlab

Simple question: Is there any built in function for images that acts similar to imagesc in matlab, i.e. take grayscale image scale it to use full [0,1] range and then use some kind of colorgradient to ...
335 views

### Understanding “IntensityData” coordinates

Update - Playing around a bit, is it true that we need to process the list of "IntensityData" values $r$ as follows: r = Partition[r,k]; r = Transpose@r; And ...
2k views

### Measure perimeter of black edge in Mathematica

I have a pattern like the one below. How could I measure the total length of the perimeter of the black/white edge? This would give me a measure of spatial frequency. Any tips would be great! Thanks!
188 views

### Understanding the computation of IntensityCentroid?

If I have an image img, and I ask ComponentMeasurements to return "IntensityValues" for the ...
710 views

### Peak Signal to Noise Ratio of Images

I am filtering a blurred image, and want to evaluate the performance of Peak Signal to Noise Ratio (PSNR) in Mathematica version 9.0. But I am facing the problem of evaluating the PSNR. Could anyone ...
1k views

### Identifying and counting closely spaced particles

Following in the footsteps of this blog post: http://blog.wolfram.com/2011/09/09/building-a-microscopy-application-in-mathematica/, I took a microscope picture of some particles on a surface, and ...
471 views

### Image Processing Mag and Phase Spectrum of Sobel, Roberts Mask [closed]

How to find the Magnitude and Phase Spectrum of Sobel, Roberts etc. etc. Mask of Image Processing using MATHEMATICA 9.0 platform....
408 views

### Cropping an image to a minimum bounding box for a set of points

Imagine a define a pointlist inside of an image: Provided a pointlist for the set of red dots around the toy horse, is there a way for me to automatically crop to a minimum bounding box for this ...
486 views

### Defining and isolating a region of an image internal to a bounding curve

I was recently looking over this very nice question by March Ho: Counting elements which are inside another element on a different colour channel There are often times where I find myself wanting to ...
249 views

### Can I use SelectComponents with measurements that take into account the value of underlying pixels?

Normally, we can ask for the mean, median, etc. underlying pixel values for morphological components with the command: ...
303 views

### How can I use SelectComponents to select for components that have a pixel within a certain RGB range within their convex hull?

I calculate a set of morphological components: Components = MorphologicalComponents[Binarize[image,0.1]]; We can now use SelectComponents to filter for ...
618 views

### Counting elements which are inside another element on a different colour channel

I have a 3-channel image which shows red and green points (certain labelled proteins) inside blue regions (cell nuclei). After applying some segmentation filters, the resulting image is as follows: ...
308 views

### How can I detect and modify one area of an image while preserving the rest

I have an image with a big black disk bounded by a white boundary in its center. The image contains some other stuff outside of the spot and its boundary. This stuff has colors which include both ...
322 views

### How Can I Transform a Colored Image into Pre-defined Matrix?

I am new to Mathematica and I would like to use it to postprocess some of the experimental data I measure. I would like to visualize voltage measurements over a non-uniformly segmented plate. I would ...
188 views

### Formatting the output of ComponentMeasurements

I have some code written here which uses ComponentMeasurements to output some data, specifically the one below: ...
189 views

### ImageLines Segmented options

I have tried utilising the ImageLines function, and its accompanying Segmented setting. However, the segmentation doesn't appear to allow for its variables to be fine tuned, at least not according to ...
634 views

### Removing the edge features of an image while enhancing internal connectors

I picked up the following leaf today while going for a walk. And wanted then to run the same analysis that @Vitaly Kaurov did for rivers under this posting Measuring Fractal Dimensions of natural ...
297 views

### Is there a fast method of generating a Standard Deviation image from a frame stack?

Imagine I have a stack of image frames, $(f_1, ..., f_N) \in F$, where each $f_i$ has the same set of $(x,y)$ dimensions. Using these frames, I'd like to create an image where each pixel in the image ...
633 views

### Problem with Fourier and InverseFourier function

I have the following code Image[img, ImageSize -> 300] data = ImageData[img]; fdct = Fourier[data] tdata = InverseFourier[fdct]; Image[tdata] but it seems to ...
304 views

### Defining a polygon by clicking on an image [duplicate]

Imagine I have some image, $I$, and I'd like to define a polygon by sequentially clicking on the image to define vertices $(v_1, ...) \in V$, where vertices $v_i$ and $v_j$ share an edge if $j = (i+1)$...
7k views

### Calculate the 2D Fourier transform of an Image

I am new to Mathematica, and using version 8.0. I would like to calculate the 2D Fourier Transform of an Image with Mathematica and plot the magnitude and phase ...
409 views

### Intersection & Complement operations for lists of Morphological Components?

I have an array of $M$ sets of morphological components corresponding to the same image, however computed in different ways. For example, we might have: ...
653 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 ...
540 views

### Adjusting the pixel values underlying a morphological component when computing an “IntensityCentroid”

When calculating an "IntensityCentroid" with ComponentMeasurements, i.e. for an image $I$ and set of components $C$, calculating:...
411 views

### Selecting morphological components, of a certain size, centered on points of interest in an image

I have a set of points in an image, for example: ...
364 views

### Use TextRecognize to grab timestamps from a video frame

I have microscope videos that have a timestamp overlay to them, and it would be great if I could extract this for each frame to add to my metadata. TextRecognize ...
138 views

### Is there an easy way to create a “IntensitySquaredCentroid” using ComponentMeasurements?

One of the options in ComponentMeasurements is to compute a centroid based on the pixel values of some underlying image. We can write: ...
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### 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 ...
683 views

### Image Processing: Concrete test blocks

Background Concrete is mixture of aggregates and cement. Aggregates are composed of different sizes and colors. Core samples are taken by drilling in order to test the strength of concrete . They are ...
840 views

### Improve TextRecognize[] on numbers

I have an image contain only numbers, and TextRecognize fail to recognize some numbers: img=; TextRecognize[img] (*826718*) The documentation says that "The ...
567 views

### Derive a smooth circle with cusp from an image

question 1 get the center (sample data) sample is the black circle with cusp. ...
2k views

### Find radii of concentric circles in image

I have an image of concentric circles, I would like to find the radii of the circles (only the innermost few are important). I've had a go using what I could find in previous posts, but am a bit ...
2k views

### Digital filter of image in Fourier space

Consider the contour plot below, of a function f(x,y) - which is calculated numerically by solving some equations. If one looks carefully, one can observe two types of waves, to the left and right of ...
521 views

### Image Restoration

I want to degrade the image, and then execute the restoration, such as a lena.jpg. I tried this: ...
564 views

### Getting RGBA data from an image

What is going on with returned data in the following examples? It appears ImageData returns different types depending on the what data is passed into ...
794 views

### Twirl Image Transformation

I am looking to reproduce the functionality of Photoshop's "Twirl" filter, which twists an image that originally looks like this (pulled from this page): Into this: Ideally, I'd like it to ...
191 views

### Maintaining map dimensions after using Colorize

I am trying to beautify a map by using Colorize as demonstrated in the Mathematica documentation. First, I import a shapefile from DIVA-GIS for France which ...