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6
votes
1answer
115 views

Get 2d corner coordinates / layout using edge detection

I'm new to Mathematica but I found an interesting usage of it: I'm programming a 2D game, with a top-view, where I'd like to have the edge coordinates of the walls. EdgeDetection delivers me quite a ...
1
vote
0answers
86 views

Can not understand the code to plot Fourier Series approximation of the line

I'm reading the CDF file from Making Formulas… for Everything in wolframalpha blog. When I step into In[9] and In[10], I'm fully confused. Who can tell me what does the two functions mean? The ...
4
votes
1answer
71 views

How to translate image points position(row, column) to their coordinate(x,y)?

Here is the code to find image edge and record the morphological connected pixels positions. How to translate the row/col positions to x/y coordinates? ...
6
votes
2answers
186 views

How to use Mathematica to turn a picture into low poly style?

I want to use Mathematica to turn a picture into low poly style. That is, to make the following conversion: Bill to Bill low poly(Using Image Triangulator App). I think the biggest difficulty is how ...
2
votes
1answer
93 views

ContourPlot is slow and unwieldy and generates a large-data graphic [closed]

I'm constructing a single contour showing the points in a plane that satisfy a function. The general form is ContourPlot[f[x, y] == 0, {x, 0, .5}, {y, 0.2, .5}] ...
2
votes
2answers
168 views

Binarizing a matrix

I have an image with a few bright pixels with the remaining ones very dark. The difference is in orders of magnitude. I want to binarize this matrix (corresponding to the image) making all values ...
0
votes
0answers
48 views

Marking certain detected points on an image [duplicate]

I have an image in which I had to detect bifurcation points of vessels. I manage to do that and now I have an image where these bifurcation points are 1 while all others are zero. What I want to is ...
2
votes
1answer
117 views

Moment central of a binary image

I am implementing the Hu set of invariant moments detailed here Hu set of invariant moments. I implemented the moment Image like this: ...
2
votes
2answers
152 views

Set PointSize to pixel size

I have a set of 1million 2D points and I would like to produce an image 200x200 pixels where each point will have the size of a pixel (no more). Additionally each point may repeats several times so I ...
3
votes
0answers
245 views

Masked Image Registration/Alignment/Correlation

I'm trying to register (align) two circular grayscale images using a boolean mask to prevent them simply being aligned on the fixed circular border. There are also small fixed circular regions in the ...
0
votes
1answer
190 views

Calculate the centroid of a group of pixels with the same PixelValuePositions

My question is about how to recognise objects in a image. I would like to recognise objects of the same color. Then I want to calculate the centroid of these objects. I want to apply this calculation ...
4
votes
2answers
316 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
1answer
253 views

How to make a big image/dashboard containing various data-graph

I want to make and image/dashborad (to export to PDF) with many VERTICAL bullet graphs gauges. And I can´t make it, in a automatic way. In general, the questions are: QUESTION 1: How to make a ...
4
votes
2answers
173 views

Upsampling matrix by inserting zeros inbetween elements

I want to essentially take an image with $n \times n$ pixels and expand it into a sparse array, spacing out the pixels by a factor $2$ or $3$. Each pixel in the input image occupies one of the corners ...
5
votes
1answer
200 views

measure minimum distance of dots from edge

I want to measure minimal distance of small dots from the edge of an image: Image of bright dots: Edge image ImageAdd looks like following:
-1
votes
2answers
137 views

Save a sequence of images using table with 2D variables [closed]

How can I save a sequence of images with 2D variables using Table. I get a Iterator {r,{-1,-1},{1,1},{0.1,0.1}} does not have appropriate bounds. >> error ...
7
votes
4answers
521 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
0answers
276 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 ...
19
votes
2answers
692 views

Why does ImageData need four times more memory?

Background We are dealing with very large TIFF image files that are imported, processed and exported using Mathematica 9.0.1. Many of our algorithms only work with an array representation of the ...