Questions on the image processing capabilities implemented in Mathematica.

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1
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1answer
148 views

Efficiently determining if a morphological component overlaps a polygon with vertices at real number coordinates

I have a list of morphological components $m$, a set of vertices for a polytope $P$ (at real number coordinates), and I'd like to be able to calculate a list of morphological components $m'$ that ...
13
votes
1answer
461 views

How to identify chemical substance from tattoo?

A friend of mine made a tattoo on his chest of some chemical substance formula. He challenged us to identify which substance is that. I thought that perhaps a combination of: Mathematica image ...
2
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1answer
106 views

Selecting for morphological components that do not border the edges of an image?

Is there an easy way to select for morphological components which do not border/touch the edges of an image? Taking this doodle as an example: We'd want to only select morphological components ...
12
votes
2answers
455 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 ...
4
votes
1answer
266 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 ...
1
vote
2answers
156 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: ...
1
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0answers
45 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 ...
13
votes
3answers
329 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: ...
9
votes
1answer
642 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 ...
0
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0answers
210 views

Metric Parameters such as Pratt Figure of Merit (Pratt-FOM) for Edge Detection

I have developed a new algorithm in Mathematica v9.0 for the Edge Detection and want to compare it with the existing Roberts, Sobel, Prewitt etc, operators in the presence of Noise. I have evaluated ...
1
vote
1answer
143 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 ...
2
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0answers
204 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 ...
14
votes
4answers
512 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! ...
1
vote
1answer
132 views

Understanding the computation of IntensityCentroid?

If I have an image img, and I ask ComponentMeasurements to return "IntensityValues" for the ...
-2
votes
1answer
265 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 ...
4
votes
4answers
356 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 ...
-4
votes
2answers
243 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....
0
votes
3answers
169 views

Quickly converting pixels of one value to another [closed]

I hope this isn't too trivial a question, but how can one quickly convert pixels in an image with one value, e.g. {r,g,b} = {0.0000,0.0000,0.0000}, to another, e.g. ...
5
votes
1answer
180 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 ...
2
votes
3answers
223 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 ...
1
vote
1answer
112 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: ...
1
vote
1answer
95 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 ...
7
votes
1answer
226 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: ...
3
votes
2answers
173 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 ...
0
votes
1answer
190 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 ...
0
votes
3answers
85 views

Formatting the output of ComponentMeasurements

I have some code written here which uses ComponentMeasurements to output some data, specifically the one below: ...
1
vote
1answer
112 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 ...
7
votes
1answer
261 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 ...
3
votes
3answers
190 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 ...
1
vote
1answer
251 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 ...
1
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3answers
162 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 = ...
-5
votes
1answer
1k views

Determine the 2D-Fourier transform of an Image

I am new to Mathematica and using Version 8.0. I want to calculate the 2D-Fourier Transform of a digital image and see its Magnitude and Phase Spectrum, and reconstruct it.
2
votes
2answers
178 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: ...
1
vote
3answers
288 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 $C$, ...
1
vote
1answer
181 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: ...
10
votes
1answer
203 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 ...
1
vote
1answer
109 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: ...
1
vote
2answers
188 views

Understanding the coordinate system for ImageTake

I have a point in an image which I can locate by right clicking and using my mouse. Call this point $p = (100,100)$. I'd like to use ImageTake to grab an image, centered on this spot $p$ with $k = ...
6
votes
4answers
3k views

Fitting a two-dimensional Gaussian to a set of 2D pixels

Imagine I have a set of data like the following: ...
0
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1answer
106 views

Returning a bounding disk or box centered on a coordinate in a 2D image

Provided a coordinate $c_k$ in a two-dimensional image, how can I return all of the pixels in a bounding disk or rectangle centered on $c_k$ of some specified dimension $d$? Update: Hat tip to Kuba ...
17
votes
1answer
315 views

Color scheme used by Colorize?

The Colorize function is often used to display the results produced by MorphologicalComponents: ...
0
votes
1answer
111 views

Returning lists of pixels connected through their Moore neighborhoods

I have a binarized image in Mathematica 9, and I would like to generate a list of coordinates for clusters of pixels connected through their Moore neighborhoods, e.g. ...
3
votes
1answer
205 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 ...
8
votes
3answers
380 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 ...
7
votes
2answers
228 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 ...
0
votes
3answers
354 views

Derive a smooth circle with cusp from an image

question 1 get the center (sample data) sample is the black circle with cusp. ...
21
votes
2answers
827 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 ...
15
votes
4answers
736 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 ...
1
vote
2answers
261 views

Image Restoration

I want to degrade the image, and then execute the restoration, such as a lena.jpg. I tried this: ...
5
votes
3answers
257 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 ...