Questions on the image processing capabilities implemented in Mathematica.

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12
votes
2answers
252 views

Why does DominantColors keep shuffling the order of the results?

This graphic is produced by running DominantColors (new in Mathematica 9) with different values, using the Lena image as the source: Each row is a list of the ...
29
votes
1answer
2k views

FindFaces: how to improve the results of the face recognition feature

In Mathematica 9, the FindFaces command offers an easy way to detect faces. In some experiments, I've been getting reasonable results, but I'd like to know if there ...
6
votes
2answers
1k 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 ...
4
votes
2answers
267 views

How can I superimpose points or disks on an image at specified coordinates?

I have a TIFF image of 640 x 640 pixels, over which I would like to plot a list of points or disks of small radius. I have been testing different alternatives and I found ImageCompose command. ...
11
votes
2answers
1k views

Push-pin Art – Convert image to R-Y-B-W-Blk color space

After seeing an example of what is called “Push-pin Art”, I assumed that Mathematica would be able to handle the kind of image processing required to convert an image to this format. I am not well ...
9
votes
2answers
832 views

How to transform a 3D image by an affine transformation matrix

I have a question concerning Image Processing: I have a stack of images, which I can compose to a 3D image using Image3D. Additionally I have a 4x4 affine transformation matrix. I would like to ...
2
votes
2answers
210 views

Take part of image under locator

How to create Manipulator with Locator to take part of an image?
26
votes
2answers
608 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 ...
10
votes
1answer
613 views

Count Elements in Image

I have the following image: img1 I'm trying to count al these colored cells and draw a circle around them. I really don't now how I can use SelectComponents for ...
5
votes
2answers
400 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 ...
10
votes
2answers
228 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"] ...
1
vote
1answer
492 views

HOG descriptor for image processing

I did not find in Mathematica a function for Histogram of Oriented Gradients (HOG) descriptors. Is there any similar function? Do you have an implementation you are willing to share?
28
votes
1answer
1k views

The correct way to linearize colorspace before resizing, blurring etc

There was an interesting discussion on MathGroups dealing with the fact that image-processing functions in Mathematica (and many other software, including Adobe Photoshop) work with RGB, Grayscale ...
20
votes
2answers
592 views

How to retrieve the parameters calculated and used by ImageAdjust?

When ImageAdjust is called with an image, i.e. with one parameter, it returns an automatically adjusted Image. I would like to ...
2
votes
3answers
592 views

Color mixing or blend

Color mixing seems not only one type. Here is RGB_color_model I wrote this one: ...
12
votes
2answers
625 views

Finding the Centroid of the grid

Im trying to automate the processing of my shooting targets to measure my performance in the range. I was able to process the shots, but I still have to select the center of the target by the use of ...
5
votes
1answer
393 views

Accessing the graph Thinning produces without losing all the edges' lengths/slopes

This is a follow up to the OCR question I had earlier. What I want to do is to use Thinning to create "skeletons" of images of characters and then compare their shapes, utilizing such properties ...
41
votes
2answers
2k views

Detecting grid lines in a raster image

Motivation: Last October 7 there was a presidential election in Venezuela. Although the opposition saw an unprecedented increase in its votes, the government votes increased even more resulting in the ...
0
votes
0answers
93 views

How to make 3d solid volume from set of images [duplicate]

Possible Duplicate: How to show solid bodies using volumetric rendering? I have a set of images, and I want to construct a z-stack, then reconstruct it to a 3d volume. My previous ...
9
votes
2answers
1k views

Overlapping accurately Images and Graphics (without loss of resolution)

Context In a previous post, I learned how to produce these kind of plots, which are of interest in astrophysics and geophysics. I am now interested in combining them. Attempt For this purpose, ...
44
votes
1answer
3k views

Measuring fractal dimension of natural objects from digital images

This is a useful topic. A college physics lab, medical diagnostics, urban growth, etc. - there is a lot of applications. On this site by Paul Bourke about Google Earth fractals we can get a high ...
10
votes
1answer
1k views

Implementing OCR without using TextRecognize

I am new to Mathematica and trying to figure out whether it is a good tool for algorithmic exploration. So I had the idea of implementing a simple OCR with Mathematica, just using standard ...
9
votes
0answers
322 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 ...
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 ...
7
votes
0answers
290 views

Cluster a signal into areas of equal intensity

Introduction I have a greyscale photograph that I want to partition into areas of equal intensity. This means, that the integral over each partition should be (roughly) equal. There is no unique ...
160
votes
2answers
37k views

Help find a bright object on Mars!

In today's news, scientists found a bright object on one of Curiosity's photos (it's near the bottom of the picture below). It's a bit tricky to find - I actually spent quite some time staring at the ...
26
votes
3answers
3k views

How to find circular objects in an image?

How could I use morphological processing to find circular objects in an image? More specifically, I need to detect road signs. I need to get the "80 speed limit" sign from this image:
17
votes
1answer
2k 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 ...
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 ...
11
votes
1answer
826 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. ...
16
votes
3answers
1k views

False Color SEM image with Mathematica

I have a question regarding colouring and binary image filtering, but unfortunately, the system doesn't permit the inclusion of images for first-timers. If anyone would like to see the images ...
16
votes
2answers
680 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: ...
9
votes
1answer
504 views

Monospaced fonts are not monospaced

I'm using Linux-x86-64 as operating system. Can someone explain this behaviour and maybe give a hint how to resolve it? Here are two lines of exact the same number of letters of a monospaced font: ...
13
votes
4answers
577 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
1answer
250 views

Problems with images caused by which stylesheet is used

Update This looks now like it was a bug in Mathematica version 8, because everything works as expected - at least for this minimal example - in version 9. (As an aside, I couldn't seem to find ...
34
votes
3answers
2k views

Identifying critical points/lines of 2/3D image/cubes

Upshot I am interested in identifying critical points of a 3D field/cubes (maxima, minima, tube-like and wall-like saddle points) and 2D field/image (maxima, minima, saddle points). I.e. the ...
5
votes
3answers
306 views

Inserting button in image

Can I insert a button in an image at specified location? I have tried but it shows Button is not a graphic function.
19
votes
2answers
1k views

How can I create a glass distortion effect in an image?

I'd like to overlay a glass jar onto an image with realistic light bending. Can anyone think of a way to automate this effect (perhaps this can be done with the raytracing package rayica)?
53
votes
3answers
6k views

Programmatic approach to HDR photography with Mathematica image processing functions

The High dynamic range imaging (HDR or HDRI) direction in photography and image processing became very popular recently. Besides obvious photo art applications (see examples), there are many great ...
35
votes
4answers
2k views

Remove image background of headshot in Mathematica?

For example, using ExampleData[{"TestImage", "Girl2"}]: what's a general way to make the background transparent? I've tried various combinations of ...
6
votes
2answers
387 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 ...
11
votes
4answers
588 views

Reproducing Image Patterns with Mathematica

Surfing on the net I stared at this pattern. It´s a bamboo steam, and it´s awesome. I'm new to Mathematica so I'm a little lost, I'd like to try to reproduce this pattern, of course in a very ...
3
votes
2answers
153 views

How to create an ImagePartition type-of-function that generates parts of different sizes

Background: I partition images to polygons ( squares ) and color them with VertexColors. I want to use a minimal number of polygons while still showing a clear resemblance of the original image. - ...
12
votes
2answers
1k 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 ...
2
votes
1answer
340 views

non-linear trend reduction using thresholds

Doing some mappings of the earth magnetic field results in the left-hand figure below (which consists of 181 profiles): To improve this I tried a non-linear trend reduction using, for example, ...
12
votes
2answers
977 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 ...
50
votes
5answers
8k views

How to create hedcut style images?

Yesterday the hedcut style was brought up in chat. How can we create a hedcut-like style automatically in Mathematica, using a photograph as a starting point? I am looking to create a similar ...
6
votes
3answers
264 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 ...
26
votes
5answers
1k views

Create magnified call-out loupe effect on image

I'm trying to create a Mathematica Manipulate that generates a graphical call-out using a 'loupe'-style or magnifying glass enlarger - a possible solution is shown ...
65
votes
11answers
5k views

Artistic image vectorization

The question is how can we use Mathematica to create vectorized versions of low-resolution images? The goal is to get an image suitable for quality printing at any resolution. Since "true" ...