Questions on the image processing capabilities implemented in Mathematica.

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18
votes
1answer
440 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
635 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
994 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
272 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
361 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
240 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
548 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
452 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
403 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
2answers
231 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
732 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
700 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
894 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
989 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! ...
13
votes
1answer
421 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? ...
9
votes
0answers
348 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
331 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
279 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
353 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
458 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
943 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
502 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
446 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
103 views

Apply ColorFunction to an Image

is there a faster way to change the colors of an image from grayscale to something like this: ...
4
votes
1answer
271 views

How to get better quality EPS graphics

Yesterday, I was doing any Tables of 15 graphs similar to the next example, to save .eps and use in latex. In the generation of the graphs Mathematica spends many time. Is possible to reduce this ...
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
451 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
257 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
227 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
349 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
2answers
150 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
210 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
161 views

Understanding the computation of IntensityCentroid?

If I have an image img, and I ask ComponentMeasurements to return "IntensityValues" for the ...
1
vote
2answers
345 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
402 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
823 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
520 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
87 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 ...
3
votes
2answers
193 views

Using high RasterSize or ImageResolution changes contour pattern

I found that the detailed contour pattern will be altered if we Rasterize the original graphics using high RasterSize or ...
3
votes
1answer
163 views

Resampling when using image as Texture

How to get sharp pixel boundaries with Texture? I'd like to have only black/white in the example below, no gray. ...
2
votes
0answers
91 views

How can I transfer colors from first image into second image? [duplicate]

How can I transfer colors from first image into second image, where every object from the first image should take the same object's color from first image. This images are only an example. this is ...
2
votes
0answers
138 views

Power::infy: error using FindFit [closed]

I have a 2D data to fit (the Airy type pattern from diffraction of Gaussian beam on the circular aperture). Please see the attached picture. I was going to use a function like ...
1
vote
1answer
78 views

Nothing happens when I click the mouse clicked on my graphics

I wrote codes to record list of coordinates when mouse clicked. It is expected that the coordinates should be plotted dynamically. But actually nothing happened. Can anybody help me to find the ...
1
vote
2answers
157 views

Why ColorReplace does not follow the rules specified?

I tried to use ColorReplace to change the colors obtained from MorphologicalComponents. However some of the changes didn't ...
1
vote
1answer
167 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 ...
0
votes
1answer
108 views

Vectorize pixel SphericalPlot

I have a question about Mathematica images exporting. I have created 3d (SpericalPlot) with coloring function on it and then exported it to pdf. Is there any possibility to make more vector graphics ...
0
votes
0answers
35 views

How to plot morphological stripe near the mouse-clicked position in an image? [duplicate]

I tried to use EdgeDetect and MorphologicalComponents to get the image edge elements. When I clicked on an image, I want the edge element nearby to be highlighted or plotted. Here is my code. Two ...
0
votes
1answer
142 views

Outputting a set of graphics 3D objects with positions defined by one array and colors by another? [duplicate]

I have a set of 2- or 3-space coordinates in an array, $(v_1,...,v_N)$, and an array of RGB color values (outputs from ImageValue[]) for each coordinate, $(c_1,...,c_N)$. How can I output a ...