Questions on the image processing capabilities implemented in Mathematica.

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2
votes
2answers
166 views

How can I merge multiple sets of morphological components (perhaps selected using different metrics)?

Let's say I use SelectComponents to select morphological components in an image according to some criterion, like "Elongation". Then let's say, I pull out a ...
5
votes
2answers
202 views

How can I properly Partition “IntensityData” output from “ComponentMeasurements”? (Recovering the (x, y) dimensions of a rect. morph. component?)

When I ask ComponentMeasurements to return "IntensityData" for some set of rectangular morphological components: ...
7
votes
4answers
432 views

Image correlation

I have two images from motor scan, Image1 is shifted by MxN pixels from Image2. How can I find the shift between Image1 and Image2 ? Image -1 Image -2 If we compare the shift between the images ...
3
votes
1answer
109 views

How to identify segments of colour and compare

Imagine a wide screen image projected from more than one video projector. Each projector handles a segment of the screen. The overlapping areas are corrected for within each projector. Before ...
9
votes
1answer
311 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 ...
3
votes
4answers
261 views

I want to calculate the pixel values of an image and export to a standard format

After finishing a few tutorials, I thought I was ready to calculate the pixel values of a large (smaller numbers 20x20 used here) image and export to a standard format (.jpg) but my code doesn't work. ...
2
votes
3answers
264 views

How Can I superpose an image and a graphics?

I want to superpose an image with a graphics in order to evaluate their alignment. I am writting this exemple of code. ...
1
vote
1answer
146 views

Remove overlapping red and green color

How to remove overlapping red and green color regions, leaving only red ones?
14
votes
1answer
595 views

How to remap a fisheye image?

I want to flatten a series of fisheye images by remapping them to a rectinlinear projection. To achieve this, I need to be able to remap the pixels of the image using fisheye correction formulas for ...
2
votes
1answer
286 views

Measure relative lengths of rectangular objects

I'm working on a method for measuring the relative lengths of the objects, with the intention of showing that the objects are longer in the center of the image that at the top/bottom. The image is ...
11
votes
2answers
566 views

How to improve the accuracy of this Monte Carlo simulation

A friend of mine went on an interview and he was asked to calculate the angle between the hour hand and minute hand of an analog clock when the time was 3:15. Arguably, this is a trivial problem that ...
0
votes
1answer
178 views

How to read image files in Analyze 7.5 format?

I am using GATE/Geant4 for simulating photon beams interacting with matter. For 3D dose distributions, GATE outputs the data into an Analyze 7.5 format [1]. I was wondering whether there exists a ...
11
votes
1answer
427 views

Ellipse counting from image

I have hundreds of images similar to this image: I'm looking to count the number of ellipses as well as their major and minor diameters. The ellipses are touching, hence, ...
6
votes
2answers
522 views

Band-pass filter an image

Ok so i have some HR-TEM images. In this technique fringes appear whereever a crystalline structure is present. This fringes are separated by a certain distance depending on the material, this is our ...
20
votes
2answers
546 views

Is there a Mathematica barcode reader?

Is there a Mathematica barcode image reader (much like TextRecognize) that allows the user to enter an image of a barcode and then read it to get an output string?
12
votes
1answer
388 views

Size distribution of nanoparticles from a transmission electron microscopic image

I have found a research article about Martian sand grain size determination from the image using Mathematica (Figure 2 in the linked article). They have not provided any detail of the methodology. It ...
1
vote
2answers
183 views

How to apply function f for each time value t, to each pixel from image, resulting in t images

I have a 2D array of complex values and I want to apply a function to every entry of the array, for every timepoint t in a list. I know how to apply my function to one entry for every time t in a ...
6
votes
2answers
174 views

Get information about a stack of images, without plotting it

A very long time ago I used Mathematica for a few months and found it very intuitive. Now for my work I use MatLab. I was just trying some stuff out with Mathematica again and there is something I ...
36
votes
2answers
940 views

Reconstruct text pages cut by shredder

Q1: I have a page of printed text file, but it was cut by a paper shredder (from top to bottom). You can download all the paper fragment here. There are some examples of them. How can I reconstruct ...
7
votes
1answer
226 views

Is it possible to construct a topological map of road network of Bangalore?

I saw this example wherein the CityData gives the map of a city. But this is available for a relatively small set of curated regions. Is it possible to extract ...
18
votes
4answers
389 views

Running out of memory when partitioning an image with ImagePartition

I have an Image3D object of image type "Bit16" with the dimensions 1472 x 1472 x 1472 that I would like to split into small image cubes of dimension 64 x 64 x 64 ...
9
votes
1answer
231 views

Deconvolution of Image3D object using ImageDeconvolve

I am trying to get the ImageDeconvolve function to work with Image3D objects. In the documentation of ImageDeconvolve it says: ...
4
votes
0answers
512 views

computation of gradient vector field in 3D using GradientOrientationFilter

I want to compute a 3D gradient vector field of an Image3D object using the built-in GradientOrientationFilter function in Mathematica. From the documentation I ...
9
votes
2answers
289 views

How could I use Mathematica to remove finger tips that appear in images?

I used my photo camera to "scan" a heavy dictionary. I tried to have flat images by pressing the margins of the pages with my fingers. The color of the background is (normally) black and my fingers ...
40
votes
2answers
1k views

Image segmentation and object separation in 3D using Mathematica

I currently work on an image segmentation scenario to detect cell nuclei in 3D using Mathematica. The data I have are image stacks in the TIFF file format. I would like to keep the sequence of image ...
3
votes
1answer
268 views

Generating a graph object where vertices are pixel coordinates and edges represent two pixels being in the same Moore neighborhood

I have a list of integer pixel positions, pts, and I wish to create one or more graph objects where vertices at these pixel positions share an edge if they are ...
1
vote
1answer
132 views

Generating a list of contour pixels for a morphological component

I have a set of pixilated shapes, and after transforming each shape into a morphological component, I want to be able to return the coordinates for pixels that lie on the contour of the shape. More ...
2
votes
2answers
215 views

Is there a way to parallelize the convolution component of EdgeDetect?

Provided an image like - test = Import["http://upload.wikimedia.org/wikipedia/commons/d/d5/Sunflowers.jpg"] We can run ...
3
votes
0answers
229 views

How can I create jpeg images of a given file size?

Cross-posted at Wolfram Community I would like to have a function makeJPG[megabytes_] that generates random jpg images of given file sizes with itf filesize (in megabytes) watermarked on the image ...
1
vote
1answer
161 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
496 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
votes
1answer
120 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
621 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
334 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
162 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
vote
0answers
47 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
401 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
730 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
votes
0answers
286 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 ...
2
votes
2answers
419 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 ...
1
vote
1answer
158 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
votes
0answers
226 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
635 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
144 views

Understanding the computation of IntensityCentroid?

If I have an image img, and I ask ComponentMeasurements to return "IntensityValues" for the ...
-2
votes
1answer
351 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
451 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
272 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
195 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
206 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
250 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 ...