Archive for the ‘Tutorials’ Category
Hi there,
This is a follow-up of my previous post: Setting up OpenCV 2.3 and Netbeans 7.0 on Ubuntu Oneiric 11.10. A couple of days ago Gijzelaar’s PPA for OpenCV has updated from 2.3 to version 2.3.1. So I thought I’d share this with you guys. I also think this is a slightly better approach
OpenCV (Open Source Computer Vision Library) is a library of programming functions mainly aimed at real time computer vision, developed by Intel and now supported by Willow Garage. It is free for use under the open source BSD license. The library is cross-platform. It focuses mainly on real-time image processing. (Wikipedia)
The upgrade did leave my machine with some broken packages, so be cautious! I managed to fix the broken packages, but that’s another story and it probably was a rare case.
Okay, so here is a quick guide:
1. Installation of OpenCV 2.3.1
Launch a terminal and execute these commands. This adds the PPA of our friend Gijs Molenaar, which now contains OpenCV 2.3.1.
$ sudo add-apt-repository ppa:gijzelaar/cuda
$ sudo add-apt-repository ppa:gijzelaar/opencv2.3
$ sudo apt-get update
$ sudo apt-get install libopencv-dev
2. Installation of Netbeans 7.1
Ubuntu 11.10 also comes with Netbeans 6.9, just download the Netbeans 7.1 from the Netbeans Homepage and you’re all set. Be sure you download the version with C/C++ support.
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I don’t like Eclipse. There, I said it. However, in the past Netbeans and C/C++ didn’t play along. Since I upgraded to Ubuntu 11.10, I decided to give it another go, and the results are pleasing! As there was no install guide available online for my situation, I decided to summarize the steps I used in order to get things running.
OpenCV (Open Source Computer Vision Library) is a library of programming functions mainly aimed at real time computer vision, developed by Intel and now supported by Willow Garage. It is free for use under the open source BSD license. The library is cross-platform. It focuses mainly on real-time image processing.
1. Installation of OpenCV 2.3
First of all, Ubuntu 11.10 comes with OpenCV 2.1, and I wanted 2.3. Luckely our friend Gijs Molenaar provides us with a PPA for OpenCV 2.3.
$ sudo add-apt-repository ppa:gijzelaar/cuda
$ sudo add-apt-repository ppa:gijzelaar/opencv2.3
$ sudo apt-get update
$ sudo apt-get install libopencv-dev
(Little notice: the package that comes with Ubuntu 11.10 is called libcv-dev, however in the PPA of Gijs the package is called libopencv-dev)
You might also want to install other packages related to OpenCV, just search for them in the Ubuntu Software Center. However, libopencv-dev will do.
2. Installation of Netbeans 7.0
Ubuntu 11.10 also comes with Netbeans 6.9, just download the new version from http://netbeans.org and you’re all set. Be sure you download the version with C/C++ support.
3. Set the project properties
Then create a new C/C++ project in Netbeans 7.0. First, set the project properties correctly. These settings worked for me.
In the C++ Compiler dialog add “/usr/locale/opencv2″ to the “Include Directories” field, also do this in the Linker dialog. In the Linker Dialog, also add the libraries opencv_core and opencv_highgui. You can find these libraries directly under “/usr/lib/”.
4. Set the includes
#include <opencv2/core/core.hpp>
#include <opencv2/highgui/highgui.hpp>
I find it easy to work with the cv and std namespace by default, so I don’t have to type “cv::” before every function.
using namespace cv;
using namespace std;
And if we put this all together in to a little program that shows an image, you have something like this:
#include <opencv2/core/core.hpp>
#include <opencv2/highgui/highgui.hpp>
#include <iostream>
using namespace cv;
using namespace std;
int main(int argc, char *argv[]) {
Mat image;
image = imread(argv[1], CV_LOAD_IMAGE_COLOR);
if (!image.data) // Check for invalid input
{
cout << "Could not open or find the image" << endl;
return -1;
}
namedWindow("Display window", CV_WINDOW_AUTOSIZE); // Create a window for display.
imshow("Display window", image);
return 0;
}
There we go: Our first OpenCV program in Netbeans! I hope this will work for you too

MamppControl
Hey,
Yesterday I had some spare time, so I decided to take a look at the Cocoa collection of frameworks, APIs, and accompanying runtimes that make up the development layer of Mac OS X.
I’ve created this first application with XCode in Objective-C and named it MamppControl.
It allows you to start, stop, reload Mampp from the tray, with a handy tray icon & menu.
Mampp is the other name for Xampp on Mac.
XAMPP is an easy to install Apache distribution containing MySQL, PHP and Perl. XAMPP is really very easy to install and to use – just download, extract and start.
More information about Xampp here.
I know that there is a launcher includes in the xampp package, but it has no tray icon and stay’s visible in the dock.
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Hi,
As a PHP developer it comes in handy to run your websites without having to upload them to your server. You can run them on your own computer if you want to, there isn’t much to it. I also like using the CodeIgniter framework for my projects, this is a really speeds up the whole process!
I will take you through the basic steps to set up your localhost to get CodeIgniter running.
1) Use Synaptic package manager to install “apache2″, “php5″ and “mysql-server”.
During the installation you will be asked to enter the password for the root user for your mysql-server.
2) Create a symbolic link, so that when you go to localhost in your browser, you get the website you want.
sudo cd /var/
sudo rm -r www/
sudo ln -s /path/to/website www
Always look before you delete something with “rm -r”, normally there should only be a index.html file in your www/ folder.
I prefer creating a link to my website that I put somewhere in my home directory, as this is being back-upped frequently, and is on another partition.
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A missing feature in Flex is the ability to load fonts at runtime.
‘Why is this useful?’, you could ask. Well one situation is you’re creating an online rich text editor, and you want to add a font
to the font list. You would only have to edit the css and upload the new swf instead of the whole application. Or you want a client
to be able to add fonts without him having the source code from the application.
Luckily it’s possible in Flex to load runtime CSS compiled as an SWF with the StyleManager class.
StyleManager on LiveDocs
Fonts.css Example :
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| @font-face {
src:url("fonts/Arial.ttf");
fontFamily:"Arial";
} |
How to compile the CSS to SWF?
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