Closed. This question does not meet Stack Overflow guidelines. It is not currently accepting answers.
We don’t allow questions seeking recommendations for books, tools, software libraries, and more. You can edit the question so it can be answered with facts and citations.
Closed 5 years ago.
Improve this question
I am looking for information on how to draw flame fractals from googling around I could not find much, either pages explain how to use third party tools or way too complicated for me to grasp. Anyone know how/why they work? or point me in the direction of not overly complicated implementations?
I have written a beamer presentation that covers the basics in flame fractals:
https://www.math.upenn.edu/~peal/files/Fractals[2009]Beamer[Eng]-PAXINUM.pdf
All images are done from my java implementation of the flame algorithm.
The source code can be found here:
http://sourceforge.net/projects/flamethyst/
I believe that the pdf http://flam3.com/flame_draves.pdf together with the implementation in java above should get you a long way.
You could read the original paper by Scott Draves, which details precisely how and why they work, as well as a guide to an implementation in pseudocode.
As long as you have some basic knowledge of maths, it should be relatively straightforward to understand (though it is rather long!). To be honest, you can probably ignore much of it and just read about the code, since much of the text is background info.
Fractal flames are basically a variant of an iterated function system (IFS). You have a series of functions through which you pass a single point over and over again. Each function is a combination of an affine transformation and one or more variations.
Each iteration, only one function is chosen (at random), and the resulting point is accumulated into a buffer and used as the starting point of the next iteration.
The buffer is then saved as an image, after having been post-processed and filtered, as described in the flame paper.
The best reference is still the original implementation, flam3.
I think fractals would be too computationally expensive to do in real time.
If I Google "simulating fire in computer graphics" I get a number of interesting things that suggest that it's not a trivial problem (surprise). SIGGRAPH is a conference whose proceedings you'll want to check out. But be warned - this is very mathematically challenging.
Have a look at http://formulas.ultrafractal.com/
There you can download the "Completed Formula Pack"
The file enr.ucl file should contain the formula for the flame fractal.
For more info:
http://www.ultrafractal.com/kb/flamefractals.html
Related
Closed. This question does not meet Stack Overflow guidelines. It is not currently accepting answers.
We don’t allow questions seeking recommendations for books, tools, software libraries, and more. You can edit the question so it can be answered with facts and citations.
Closed 8 years ago.
Improve this question
I am planing to develop an app like Word Lens. Can any one suggest a good library that I can use? or any one explain technology behind the Word Lens App? is it reel time image matching or OCR? I know some image processing library like OpenCv, tesseract...Any help is greatly appreciated...
I'm one of the creators of Word Lens. Although there are some OCR libraries out there (like tesseract), we decided to make our own in order to get better results and performance. Our general algorithm goes like this:
copy the image from the camera and get its grayscale component
level out the image so the text stands out clearly against the background
draw boxes around things that look like characters & sentences
do OCR: match the pixels in each box against a database of characters -- this is actually pretty hard!
collect the characters into words, look up in a dictionary (this is hard too, because there will be mistakes in the OCR)
draw the results back onto the image
Image matching by itself is not good enough, because of the huge variety of fonts, words, and languages out there.
OpenCV is a great library to get up and running with, and to learn more about computer vision in general. I would recommend building off their examples, and playing around there. Have fun!
Closed. This question does not meet Stack Overflow guidelines. It is not currently accepting answers.
We don’t allow questions seeking recommendations for books, tools, software libraries, and more. You can edit the question so it can be answered with facts and citations.
Closed 2 years ago.
Improve this question
Is there any good Scala or Java library for image manipulation? For simple tasks like composing an image with some others then generating a thumb?
Take a look at https://github.com/sksamuel/scrimage (Disclaimer: I am the author)
This is an open source Scala image library that essentially wraps java.awt Image operations in a nicer API.
You asked how to generate a thumbnail, you would do something like.
val in = ...// some input stream
val out = ... // some output stream
Image(in).scale(300,400).write(out, Png)
You can change the scaling method (Bicubic by default) and the output format.
they're all a bit old school, and maybe inconvenient, but java.awt, java.awt.image, and javax.imageio has everything you need to blend and rescale images. You can find some blending example code e.g. here
http://www.curious-creature.org/2006/09/20/new-blendings-modes-for-java2d/
you can find some examples of rescaling and generating image bytes e.g. here
https://sourceforge.net/projects/ssim/?source=directory
there are probably newer/easier solutions, but these do work.
It's not Scala-specific, but ImgLib2 is a full-powered Java image processing library. It's geared towards scientific/low level use, so it might not be as easy as you want for what you're looking for, but it can almost certainly manage anything you're likely to want.
There are also a lot of nice image filters in this Open Source library:
http://www.jhlabs.com/ip/filters/
Since the question is tag with java-2d you know you can use any Java library. A quick google revealed this SO answer:
open source image processing lib in java
Closed. This question needs to be more focused. It is not currently accepting answers.
Want to improve this question? Update the question so it focuses on one problem only by editing this post.
Closed 3 years ago.
Improve this question
I want to make a program that takes an image as input and outputs text. Now I know that I can use a neural network to turn an image of single character into that character. The difficult part is: given an image with text in it, how would I produce all the rectangles around each individual character? What method could I use to do it?
A basic approach is to make a histogram of black pixels. First: project all pixels on a line. The deep valleys in the histgram indicate separation between lines (try different angles if the paper might be tilted). Then, per line (or per page if you know the font is monospaced) project the pixels on a horizontal histogram. This will give you a strong indication of inter character spaces. As a minimum this gives you a value for the average character height and width that will help you in next steps.
After that, you need to take care of kerning (where characters overlap). Find the connected pixels, possibly by first doing dilatation or erosion on the image to compensate for scanning artifacts.
Depending on the quality of the scan image you may have to use more advanced techniques, but this will get you going.
This doesn't sound like artificial intelligence, it sounds like you're talking about OCR:
http://en.wikipedia.org/wiki/Optical_character_recognition
See google tesseract
http://code.google.com/p/tesseract-ocr/
EDIT The unedited question was asking about artificial intelligence.
To me the question per se does not seem clear.
As it talks about OCR will leave a couple of articles here that they may help (they help me at least):
Improve OCR Accuracy
How to use image preprocessing to improve the accuracy of Tesseract
Also as mentioned above tesseract is a good OCR open-source python library (the one that i personally use as well). Other approaches that you may take is through sklearn
You may also want to check this stackoverflow post.
I am also pretty sure that you can use researchgate to check for any papers out there (I found some, just not sure if this is what you need)
I think that the above generic answer suits the generic question.
Closed. This question does not meet Stack Overflow guidelines. It is not currently accepting answers.
We don’t allow questions seeking recommendations for books, tools, software libraries, and more. You can edit the question so it can be answered with facts and citations.
Closed 8 years ago.
Improve this question
The documentation with the module itself is pretty thin, and just tends to point to MOP.
First you should read through the Manual if you haven't already. Then you can go on to read the Cookbook.
I think the docs are actually pretty good these days, as long as you read the right ones. You really shouldn't bother looking at most of the docs for any class name starting with "Moose::Meta" unless you're interested in Moose's introspection features. I've tried to make this more obvious in the Moose.pm docs, which as of 0.57 tell you to read the Manual and Cookbook first.
If you're coming from a background of doing Perl 5 OO "the old school way", I'd also suggest taking a look at the Moose::Manual::Unsweetened document, which compares Moose to equivalent Perl 5 "by hand" code.
http://moose.perl.org is a good central resource for all things Moose
Once you read the docs Dave mentioned, if you have some insight on how it could have been more approachable or gotten you off on the right foot (or simply been easier to find), perhaps you would like to contribute that to the documentation. The developers cannot really read the introductory documentation from a new user's point of view. So file a bug report (with a patch maybe) against the documentation and/or discuss it on the mailing list or irc channel. That will help the next person in your shoes.
I found this Moose Quick Reference sheet invaluable. I'm always forgetting in which manual section to look up a particular feature.
I too am just starting to move on to Moose. Since the term good can be rather subjective, I'll just detail what I found was good in these resources. The resources may be more or less helpful depending on your skills/experience in Perl.
I started off at this Perl Monks page. And moved straight into the Moose::Cookbok link listed at the bottom. There, the author included several more links to pods demonstrating Moose syntax and object-oriented programs. The ordering was put together well; starting with simple and basic OOP with Moose at the top, progressing to more complex examples as you go down the page. The pods are well written, aren't overly wordy, and explain each chunk of the code clearly.
I'm sure once you're done with the Cookbook, you could check out whatever else was listed at the Perl Monks page. I'm still going through the examples in the Cookbook, so I haven't checked all the resources listed at Perl Monks, but I'm sure they're good.
Closed. This question does not meet Stack Overflow guidelines. It is not currently accepting answers.
We don’t allow questions seeking recommendations for books, tools, software libraries, and more. You can edit the question so it can be answered with facts and citations.
Closed 4 years ago.
Improve this question
What I want is lots of nodes which can expand making a mind map.
I'd ideally like to expand and collapse nodes. I would like to be able to navigate by either dragging around the page, or by following expanded nodes.
I have a colleague who needed that kind of functionalities to graph Maven dependencies between projects. He ended up using FreeMind to do the visualization. He just had to write an XML file conforming to the FreeMind format. I even think you can just use OPML as the file format and find a ready to use XSLT to transform it to the FreeMind format. Maybe FreeMind actually supports OPML directly (I havent used it for a long time).
Once you have your data in FreeMind, you can either export them, or use the FreeMind applet to display an interactive MindMap on your website.
Suggest mxGraph.
Suggest protovis, lovely javascript cross-platform visualisation library.
I think you are asking for a component that does what Visio can do, except that it can be displayed on a web page. Most likely you would have to create one from scratch, because mind mapping tools are always released as products per se and not customizable components. I suggest looking for a basic drawing/illustration component, and then putting your mind-mapping logic in it.