Questions on the image processing capabilities implemented in Mathematica.

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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 ...
13
votes
4answers
630 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 ...
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 ...
11
votes
1answer
955 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
477 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
921 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
304 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
245 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
736 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 ...
18
votes
1answer
459 views

Color scheme used by Colorize?

The Colorize function is often used to display the results produced by MorphologicalComponents: ...
19
votes
3answers
1k views

Download xkcd Click and Drag comic

Inspired by the recent question about xkcd styled plots I started looking at xkcd again and I came across a comic titled Click and Drag. And if you do that, you start exploring a larger drawing. A ...
15
votes
3answers
642 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
1answer
293 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 ...
11
votes
1answer
387 views

Precise cropping with ImageCrop

The built-in ImageCrop function "effectively removes borders from image whose pixel value distribution is almost uniform" (emphasis mine). I need an efficient ...
10
votes
2answers
248 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
606 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 ...
13
votes
2answers
490 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 ...
13
votes
4answers
409 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: ...
7
votes
1answer
101 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
237 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?
5
votes
1answer
777 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 ...
3
votes
2answers
794 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 ...
3
votes
1answer
942 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
442 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? ...
10
votes
0answers
357 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
4answers
361 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
284 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
376 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. ...
5
votes
3answers
470 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
1answer
517 views

How do I put an image on the complex plane?

I watched this video and became interested in transforming an image. But I have no good idea on how to embed an image in the complex plane using Mathematica. I have a method that seems to work, but ...
5
votes
2answers
464 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
2k 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 ...
3
votes
2answers
482 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 ...
3
votes
2answers
285 views

How to superimpose contour lines on transformed image

My goal is to superimpose contours lines or contour plots on distance transformed image.
3
votes
3answers
234 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 ...
3
votes
3answers
364 views

How to find Image Size of a control object?

I want to find the ImageSize or at least dimensions of any control object irrespective of it being an image or an any other control such as ...
2
votes
3answers
259 views

Calculate pixel intensity in two regions

I am just beginning to learn about image processing. I would like to know 1) How to show an original image with a visible mask of an arbitrary shape? 2) how to calculate the pixel intensities in the ...
2
votes
2answers
215 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 ...
2
votes
1answer
163 views

Understanding the computation of IntensityCentroid?

If I have an image img, and I ask ComponentMeasurements to return "IntensityValues" for the ...
1
vote
2answers
350 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 ...
6
votes
2answers
2k views

Deformed style when exporting eps files

I want to export a plot into an eps file. Below I present a sample plot code in order to demonstrate the two issues that appear. (1). LabelStyle: When I use ...
6
votes
2answers
422 views

How do I transform a rasterized graphic's coordinates back to its original ListPlot data coordinates?

From this question I successfully made an elliptical fit for my data. However, when I try and collect the datapoints within the ellipse via this question the coordinates of my ellipse correspond to an ...
6
votes
2answers
873 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, ...
6
votes
2answers
525 views

How can I visualize features found in an image?

I am using Mathematica to explore the face detection feature of Core Image on Mac OS X Lion. To do this I have an Objective-C program which captures images from the iSight camera, runs face detection ...
3
votes
1answer
95 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.
3
votes
1answer
94 views

How to create a 1D vector by selecting a straight line in a given angle of 2D array

Suppose I have an image created by the code provided below. I want to select a line (1D vector) $ \left(y-y_{0}\right)=n\left(x-x_{0}\right) $ from the output image (2D matrix) by specifying $n$ and ...