Questions on the image processing capabilities implemented in Mathematica.

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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 ...
26
votes
4answers
1k views

Clustering of space-time data

Below is an example of a gaze sequence I recorded during a 3 seconds display. That is, where the eye was at every millisecond. While we should have 3000 points, we are missing some due to blinking. ...
16
votes
3answers
671 views

Selective blurring of areas of image to make seamless tiles

I'm trying to make seamless tiles - images that can be repeated on a grid without it being obvious where the joins are. So far, I've followed the classic strategy of getting the edges working ...
11
votes
2answers
580 views

Adding controls for multiple functions in Manipulate

I am learning Mathematica and the Image Processing functions. I have the following Manipulate procedure which works fine: ...
15
votes
3answers
624 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 ...
14
votes
4answers
836 views

What is the fastest way to locate an image inside a larger image?

let b = let c = How to do: find[c,b] that returns the bounding box of c in b? ...
13
votes
2answers
943 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 ...
2
votes
4answers
1k views

How can I extract the data from an image and process it pixel by pixel?

For example, to change the color of each pixel to the mean color of the three channels, I tried i = ExampleData[{"TestImage", "Lena"}]; Mean[i] but it just ...
6
votes
1answer
339 views

How to determine edgeweights from width of skeleton using MorphologicalGraph (or workaround)?

Background I'm trying to create a workaround for what seems to be a bug in MMA's graph functions related to edge weights: SO: How to Label Graph Edges with their weights According to MMA's ...
59
votes
3answers
5k views

Recovering data points from an image

Unfortunately, some data can only be obtained in picture form (Japanese publications anyone?). Since this cannot be worked with, it has to be converted to a dataset that can; I was wondering whether ...
6
votes
2answers
628 views

Fit an image within a Rectangle [] in Graphics

Based on the following Code (yet the white text in the image is added with PPT), I would like to have an image fit within one of the rectangle. For Example the image from there : ...
24
votes
4answers
2k views

How to make a drop-shadow for Graphics3D objects

What's the best way to make a drop shadow for a 3D object? image = Graphics3D[Sphere[], Boxed -> False] I can get a blurry black outline of this: ...
5
votes
3answers
422 views

Tile image on specific location without space between them [duplicate]

Possible Duplicate: How to combine images with the same dimensions in a grid? I would like to arrange images without any space between their edges as each piece is made to connect with ...
13
votes
2answers
248 views

Tuning ParallelMap when IO and computationally bound

I'm currently doing work on processing a number of images taken frame-by-frame from a video. As a result, I have a directory of around 16K PNG images that at most ~300K. That said, I have a routine, ...
15
votes
2answers
1k views

How to combine images with the same dimensions in a grid?

I have the following images, both 480 x 270 pixels: I'd like to stitch them side by side in a 960 x 270 pixel image like so (scaled down): So far, I've been using ...
11
votes
3answers
692 views

Image levels: how to alter 'exposure' of dark and light areas?

I was working with some less than ideal photographs, and wanted to adjust them before continuing. I wanted to raise the levels of the very dark areas and lower the levels of the very light areas. I ...
13
votes
1answer
390 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? ...