Tomograpy 3D reconstruction - matlab

I have to do a project for school and I have no idea where to start from. I need to make a 3D reconstruction from the images you get after doing a tomography.
Also, after the image will be reconstructed i need to provide a tool so the user can slice the organ as he wants and so he can see the section he made.
Any help would be really apreciated. Thanks.

See Radon function & co this is very likely what you will need to use. And see also this book (a must have reference).

A very quick Googling led me to this page. A tomography toolbox for MATLAB.

Related

3D Chemistry laboratory images for Unity

I really wish someone out there has a link to help me out with a link to free 3d animated models for Unity, I'd like to incorporate these 3D chemistry laboratory objects like, test tube, burette, Conical flask, beaker. I really wish there is someone out there to give a heads up, i'm not good at any 3d program to build these by myself.
Please your positive contributions will be most welcomed.
Archeopterix' Labware Props for Poser-Vol One:
http://www.sharecg.com/v/66895/browse/11/Poser/Archeopterix-Labware-Props-for-Poser-Vol-One
Microscope:
https://free3d.com/3d-model/microscope-64352.html
Feel free to add to my answer if you find anything else.

SIFT implementation in MATLAB Tutorial

I'm looking for some basic SIFT implementation in MATLAB. I need to write it from first principles. Also, I'm looking for something which explains whats going on in the program. Vedali's code and David Lowe's code just go over my head.
If you are a Matlab user, you must know this excelent site web : Matlab File Exchange
There, you will find the following project : Feature Points In Image
I think this project will fully answer to all your questions about sift.
It also posible to have a look of the SIFT implementation of the opencv library.
Then, you can find a matlab implementation by the SIFT inventor here :
D.LOW SIFT, I assume that you already know this implementation.
To understand SIFT, read this very good paper ASIFT wich explain the ASIFT algorithm. This paper start with a description of SIFT alogirthm.
You can have a look at this implementation by Yan-Tao Zheng, Ming Zhao, Shi-Yong Neo.
Also, I know that Scott Ettinger from Intel research made a Matlab implementation at some point.

Sample code using Core-Plot for iPhone

I'm trying to find some sample code for Core-Plot on the iPhone. So far, all the examples I've found plot equations such as X^2 or 1/X, etc. over some range. My goal is to find some sample code that just plots two points ((1,2) and (2,3), for example) and connects them with a line.
It seems simple, but I've yet to find out how to approach this. I've checked the Core-Plot Wiki, and am again only able to find more complex examples.
Appreciate any help, thank you.
Have you looked at the examples included with Core Plot? There's a mix of Mac and iOS apps. Except for the hosting view, the API is identical on both platforms.

How do I use ICC profiles on the iPad/iPhone?

right now I'm implementing a basic PDF viewer, and I came across the problem that some files are displayed with wrong (too intense, too bright) colors for text and vector graphics when rendered on the device and in the simulator.
Since I have access to calibration hardware, I could create ICC profiles for the device with test data.
The only question I have now: Is there a way to use ICC profiles to aid the rendering of PDF data on the iPad's screen?
If someone wonders: I plan to target iOS 4.x on the iPad and possibly on the iPhone.
Thanks in advance!
I worked around this issue (of having PDFs render in different colors than pre-computed preview bitmaps) by generating all PDFs using sRGB (you can select this, for instance, in InDesign export settings).
Right now, iOS lacks a system-wide CMS like ColorSync.
What I would try to do is:
calibrate your iPad,
calculate the color transform from the ICC profile your calibrator gives you,
run that transform on the color values you display from the PDF data.
See where that gets you. There may be a lot of variance across the displays you are targeting (maybe different manufacturer batches == slightly different whitepoints, or something) but maybe that will assuage your problem.
... Which, since unlike some people, you're not defining that problem for 'perfect color reproduction in iOS' and as such, your problem is most likely quite solvable.
Bruce Lindbloom has a lot of color-conversion math (constants, definitions, etc) and his site is a great place to start, for this sort of thing.
http://www.brucelindbloom.com/
Since most Cocoa devs can depend on ColorSync, I haven't run across any relevant color transformation examples in Obj-C. There are plenty in Python that I know of -- python-colormath is a good example, with legible implementations of many of Mr. Lindbloom's matrices and transformations:
http://code.google.com/p/python-colormath/
... you may also be able to embed OpenCV in your iOS project. OpenCV has native matrix data structures and other useful things for you, if you are doing this kind of thing:
http://www.cs.iit.edu/~agam/cs512/lect-notes/opencv-intro/
This is an area of interest for me, so let me know if you'd like me to elaborate on any of what I've provided. Good luck.

Visualize Friend of a Friend (foaf) graph

I wrote a script to export twitter friends as foaf rdf description. Now I'm looking for a tool to visualize the friend networks. I tried http://foafscape.berlios.de/ but for 300+ Nodes it is really slow and does a bad job on auto formatting.
Any hints for good graph visualization tools? It's ok if they do not support foaf directly, but they should be able to use images for graph nodes and be able to display large graphs. Linux support would be nice.
Oh, and I'm searching for an interactive tool where I can move nodes by hand.
Update: Thanks for your input. I know graphviz and for static images it is really great. But for large datasets I need to be able to select nodes and highlight all neighbours.
Prefuse looks great: http://prefuse.org/gallery/graphview/
trough prefuse I found vizster, which is exactly what I search (just need to find some sourcecode) http://jheer.org/vizster/
perhaps the prefuse visualization toolkit might help you. It's based on Java and has many sample apps including a graph viewer.
You could try Graphviz. It runs on Linux, Windows and Mac OS X and it will generate an image (PNG, PS, etc) of the graph. You will have to transform your foaf data into its own custom language, but it's pretty easy to learn.
I don't know of any program that auto-generates graph visualizations and allows you to interactively adjust nodes, but Graphviz is a really popular tool for graph visualization. It can export to SVG so you can edit the result in your favorite vector graphics editor.
As recommended by other posters, definitely Graphviz. It takes an input file, let's call it foaf.dot, in the following format:
graph G {
"George Formby" [shape=custom, shapefile="file:formby.png"];
"Michael Jackson" [shape=custom, shapefile="file:jackson.png"];
"George Formby" -- "Michael Jackson";
"Fred Flinstone" -- "Michael Jackson";
"Michael Jackson" -- "Steve McQueen";
}
Note that this file describes an undirected graph (hopefully your friendships are reciprocal). The syntax for directed graphs is similar.
In order to output your graph to a pdf file (assuming that you have already installed graphviz) run the following command
dot -Tpdf foaf.dot > foaf.pdf
Graphviz supports a number of output formats other than pdf, see its documentation for details.
I find that the 'dot' program usually provides the best output results, however graphviz contains a total of 5 layout programs. From the documentation:
dot - filter for drawing directed graphs
neato - filter for drawing undirected graphs
twopi - filter for radial layouts of graphs
circo - filter for circular layout of graphs
fdp - filter for drawing undirected graphs
I previously recommended Graphviz, but thought I should add another recommendation now that I have used Gephi, a newer tool than a lot of the stuff here. It's a very powerful interactive graph exploration tool which I have found much more usable and much faster than a lot of the alternatives here.
Try using Google Social Graph. In one of the talks at dConstruct08 last week there was a social graph showing the friend connections of Robert Scoble.
http://code.google.com/apis/socialgraph/
http://dconstruct.org/2008
If you're using Java, you could use JGraph.
I know Adobe Flex has a few graph visualization components out there, and of course that would enable the app to run on Flash which has an excellent penetration rate into your potential userbase. I'd Google up the Flex SpringGraph component, and check that out. There are a ton of graphing components in the wild for Flex, both paid and free versions.
Just one SpringGraph off the top of my head:
http://www.adobe.com/cfusion/exchange/index.cfm?event=extensionDetail&extid=1048510
check this forum: http://goosebumps4all.net/34all/bb/forumdisplay.php?fid=28
for some flare examples, there is a friend of a friend graph around there.
have you tried the Python-based IDE NodeBox (1.0)? That's what I used to generate these: http://givememydata.com/#images
vizster looks cool though, I'll check out that.
For large graphs, Gephi (http://gephi.org/) is very popular. It is highly customisable, with lots of layout and presentation options.