Questions on the image processing capabilities implemented in Mathematica.

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13
votes
1answer
275 views

How can I detect if an image is in or out of focus?

I need to filter out bad (blurry or ) images from a set, with some sort of blur detector.
17
votes
2answers
855 views

How to measure segment length and branch angle

I am trying to measure segment length and branch angle or bifurcation angle between each pair of segments. My image after thinning looks like this: ...
12
votes
2answers
1k views

Image Processing: Isolating areas of an image with internal irregularity

I am trying to isolate each of the blue painted fingernails in the image. However, I am not sure what approach should be considered due to the white design on each nail interrupting the otherwise ...
18
votes
1answer
3k views

Vectorizing an image like “Trace Bitmap” in Inkscape

Lately, we had a nice question about artistic image vectorization which got very nice answers. As Szabolcs pointed out himself Since "true" vectorization performed by various specialized software ...
13
votes
1answer
692 views

Image Processing: Edge detection of the tumor on tomogram. –°alculation area of the tumor

The task is to identify the image region of the tumor. I try to use example from documentation centre: ...
13
votes
2answers
2k views

How to convert an image to a graph and get the positions of the edges?

I am trying to convert an image to a graph. My image is already skeletonized and looks pretty much like this: What I need to do is identify all vertices and edges, and in particular get a list of ...
27
votes
2answers
689 views

Counting radial ridges on an image

After happily using the v9 image assistant to crop elliptically an image, and then the drawing tools to put a white disk in the middle, I turned this image: into the following one: that can be ...
24
votes
3answers
2k views

How to find the center of a circular pattern?

I am writing an algorithm that finds the center of 500 x 500 pixels images coming from a live feed from a camera at 50 Hz. So it has to be quick! The images are images of an optical field which looks ...
18
votes
1answer
1k views

Rotating perspective of an image in the z axis

A purely recreational question, but one I hoped the community would find interesting enough to suggest a way to approach it. Let me preface this question with the admission that I have done nothing ...
14
votes
4answers
653 views

Poor results with ImageLines function

I'm trying to get my mind wrapped around Mathematica's image feature recognition functions. I'm intrigued by the ImageLines function for a couple future ideas I ...
11
votes
1answer
1k views

Enlarge an image and increase its resolution

An ongoing purely recreational project. I got my introduction to image processing with this Rotating perspective... question and had a lot of fun with it. Now I want to take it to the next step. ...
13
votes
2answers
504 views

Intersecting parabolas in an image

I have a friend who is a math teacher (like me) and while out cycling took this picture. The idea would be to create the equations of the quadratics that model the bridges and super-impose them on ...
13
votes
1answer
1k views

How to map an image to get an illusion of 3D

I would like to distort or map a given jpg so it looks 3D when viewed from certain angle, as in the following youtube video: http://www.youtube.com/watch?v=IfCCUd8mFtg. The most interesting part of ...
10
votes
1answer
365 views

How can I extract the outline of bubbles in my image?

I have an image: I tried to extract the outline of the bubbles, but I met with some problems. Firstly I tried the method used in Mathematica documentation for ...
3
votes
1answer
267 views

How can I create a colour image using raw black and white data? (FITS data cube)

I have a data cube containing pictures of a galaxy across a thousand wavelengths. I want to take the data for the image slides in the red and blue parts of the spectrum, and have them represented in ...
22
votes
2answers
794 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?
20
votes
1answer
1k views

Using ImageCapture to access a USB webcam in linux

Is it possible to access a USB webcam through Mathmatica on Linux? When I run ImageCapture[] I get the following output ...
19
votes
1answer
476 views

Color scheme used by Colorize?

The Colorize function is often used to display the results produced by MorphologicalComponents: ...
15
votes
3answers
652 views

Measure a DensityHistogram[] pair similarity

I study human vision and more specifically eye-movements. "If we display 2 symmetrical patterns (20 min one after the other), will our gaze distribution be symmetric is my research question." The 2 ...
13
votes
2answers
1k views

Symmetrical image transformation for a kaleidoscope-type image

I've been trying to write a little kaleidoscope-type manipulate, using images rather than graphics, and using ImageTransformation as a way in. However, I'm starting ...
12
votes
2answers
357 views

Analyze touching particles with holes in a microscopic image

I am looking for an easy method to count individual particles in a microscopic image. It is quite difficult for Mathematica to detect them, because they are touching each other. I am quite a beginner ...
12
votes
1answer
307 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 ...
10
votes
2answers
270 views

How to extract a specific element from EXIF photographic metadata?

It's now possible to import photographs into Mathematica and import the EXIF data at the same time: i = Import["ExampleData/coneflower.jpg", "ImageWithExif"] ...
2
votes
4answers
640 views

How to calculate the position of a figure in an image?

My question is about recognising soccer players in the pitch. Thanks to Bill S who wrote an excellent script to recognise parts of the players. I found this issue after testing his solution. I will ...
14
votes
4answers
418 views

How to separate paths from the output of EdgeDetect?

I have been trying to find a way to separate the various closed paths that can be output by EdgeDetect. For example, taking the output of: ...
13
votes
2answers
537 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 ...
7
votes
1answer
139 views

How to keep the non-overlapping parts when aligning images?

I would like to stitch together a pair of images. For example: ...
7
votes
2answers
253 views

Analysis of many similar x-ray Images

From a 3d x-ray scan, I have many similar slices to analyze. Is there a way to determine the position of the three rectangles and the inner circle?
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 ...) ...
5
votes
1answer
835 views

Efficiently exporting many images as a video

I have many .gif images and I would like to export them as a single video file (I prefer .mov, but any video format is fine). But what if I have several tens of megabytes of .gif images? Is it ...
4
votes
3answers
195 views

How do I plot a filled cylinder in 3D?

All, I'm trying to plot a filled cylinder in 3D using Graphics3D and then take 2D slices of said cylinder. I know that Cylinder is officially 'filled', but the 2D ...
3
votes
1answer
1k views

Detection of horizontal lines in an image

Ok I'm trying to detect horizontal lines in an image. But the problem is that the line is quite obscure. So I'm not sure if it is even possible to extract that. I tried many different filters, but ...
15
votes
4answers
1k 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! ...
14
votes
1answer
463 views

ImageAlign doesn't always work correctly

I've been working with ImageAlign in Mathematica 8 and I'm having trouble getting it working reliably. Perhaps there are some subtleties that I'm not yet aware of? ...
11
votes
0answers
381 views

Proving (self) similarity with Mathematica - Reccurrence Plots, Similarity Plots etc

I posted this question in math.se but given the sheer tumultuous number of questions that keep appearing on math.se and also given that I am trying to accomplish this in Mathematica, I thought I'd ...
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 ...
6
votes
1answer
184 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 ...
6
votes
4answers
379 views

How do I overlay corresponding values over each frame of an animation?

I recorded a phenomenon using video capturing (phen.avi, imported into Mathematica) and simultaneous measurement of some electrical properties of that phenomenon (a ...
6
votes
3answers
311 views

Is it possible to snip a certain number of pixels from a specified side of an image, without specifying the image's final width and height?

It seems that ImageCrop allows one to specify the final size of the image. For example, ImageCrop[image, size, spec] crops ...
4
votes
2answers
232 views

FindPeaks does not smooth noise on peak?

I have experimental data which is noisy. My objective is to find the peaks. Here is a short part of the data. ...
4
votes
2answers
425 views

Recognize simple shapes in an image and color them randomly?

I have an image of polygons built from a polar function (see below). I'd like to color each triangle or quadrilateral a random color. Firstly, I'm not sure how to separate the simple shapes. ...
2
votes
2answers
362 views

How can I enhance ImageCompose to blend multiple layers?

Blend modes (or Mixing modes) in digital image editing are used to determine how two layers are blended into each other. Version 8 has functionality to perform binary and basic alpha blending but ...
8
votes
1answer
513 views

ImageTransformation: polar to cartesian

I am working on something that requires the polar transformation of some images. I implemented this transformation with ImageTransformation: ...
6
votes
2answers
928 views

Exporting images as .avi

Here's a list of images: images = Table[ExampleData[i], {i, ExampleData["TestImage"]}]; And according to the reference "Export exports a list of graphics, ...
5
votes
3answers
498 views

Detect each polygons in an image

Considering this image: Is there a way to colorize each tiles independently? My problem is that img = Import["http://i.imgur.com/Y87duSz.jpg"]; Colorize@img ...
5
votes
2answers
2k views

Exporting pictures in their correct size when using Grid [duplicate]

I have a large number of pictures, and I need to place each three of them in a grid with a certain layout. For example, if I have the following pictures: ...
5
votes
2answers
494 views

What is ImageDistance measuring?

What quantity is ImageDistance measuring, and what do the numbers mean? I found the ImageDistance command in Mathematica 9, but ...
4
votes
2answers
546 views

Image processing: extracting ordered contour

Continuing the question How to extract the edge from a set of points and its answer by Simon Woods, I would like to ask if there is a way to extract the boundary of obtained as ...
4
votes
3answers
246 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 ...
4
votes
2answers
3k views

Calculate mean and standard deviation from ImageHistogram

I am doing my PhD in Clinical Neuropsychology; I had someone helping me analyse images (.jpg pictures) in Mathematica, but it turns out this person made some really bad decisions, and well, now I have ...