Run Console Application in Qt Creater

There is a bug when you try to run in terminal, it does not take any input or output.

To fix this bug on Ubunut,

Tools --> Options --> Environment --> General 

Change the Terminal from
x-terminal-emulator -e
to
/usr/bin/xterm -e

Thanks to https://bugs.launchpad.net/ubuntu/+source/qtcreator/+bug/566387

Configure OpenCV 2.4 for Qt Creator on Ubuntu

First install Qt creator using Ubuntu Software Center

Open Qt Creator

File --> New file or project
Qt Widget Project --> Qt GUI Application --> Choose

Click Next for all.

Open .pro file and add the following lines

INCLUDEPATH += /usr/local/include/opencv
LIBS += -L/usr/local/lib
LIBS += -lopencv_core
LIBS += -lopencv_imgproc
LIBS += -lopencv_highgui
LIBS += -lopencv_ml
LIBS += -lopencv_video
LIBS += -lopencv_features2d
LIBS += -lopencv_calib3d
LIBS += -lopencv_objdetect
LIBS += -lopencv_contrib
LIBS += -lopencv_legacy
LIBS += -lopencv_flann
LIBS += -lopencv_nonfree

Save it.

Open .ui file.

Drag and drop a PushButton to window.
Click PushButton and chage the follwong properties

• objectName: btnDisplay
• text: Display

Right click PushButton --> Go to slot --> clicked() --> Ok

Include the following

#include <cv.h>
#include <highgui.h>

Add the following code

void MainWindow::on_btnDisplay_clicked()
{
    cv::namedWindow("Disp");
    cv::VideoCapture cap(0);
    cv::Mat frame;
    do{
        cap >> frame;
        imshow("Disp",frame);
    }while(cv::waitKey(30)<0);
    cv::destroyAllWindows();
}

Run it. You will see yourself on the screen, when you click Display button !!!

Install Eclipse in Ubuntu

Downloaded Eclipse from website
http://www.eclipse.org/downloads/

 If your downloaded file is eclipse-cpp-juno-linux-gtk.tar.gz

tar -xvf eclipse-cpp-juno-linux-gtk.tar.gz
cd eclipse
chmod +x eclipse
cd ..
mv eclipse /opt
gedit /usr/share/applications/eclipse.desktop

Copy the following and save it.

[Desktop Entry]
Name=Eclipse
Type=Application
Exec=/opt/eclipse/eclipse
Terminal=false
Icon=/opt/eclipse/icon.xpm
Comment=Integrated Development Environment
NoDisplay=false
Categories=Development;IDE
Name[en]=Eclipse

cd /usr/local/bin
ln -s /opt/eclipse/eclipse

Eclipse is ready

Install OpenCV in Ubuntu 12.04

Copy the following script to gedit and save as opencv.sh . Open terminal.
chmox +x opencv.sh
./opencv.sh

This will complete opencv installation

arch=$(uname -m)
if [ "$arch" == "i686" -o "$arch" == "i386" -o "$arch" == "i486" -o "$arch" == "i586" ]; then
flag=1
else
flag=0
fi
echo "Installing OpenCV 2.4.3"
mkdir OpenCV
cd OpenCV
echo "Removing any pre-installed ffmpeg and x264"
sudo apt-get remove ffmpeg x264 libx264-dev
echo "Installing Dependenices"
sudo apt-get install libopencv-dev
sudo apt-get install build-essential checkinstall cmake pkg-config yasm
sudo apt-get install libtiff4-dev libjpeg-dev libjasper-dev
sudo apt-get install libavcodec-dev libavformat-dev libswscale-dev libdc1394-22-dev libxine-dev libgstreamer0.10-dev libgstreamer-plugins-base0.10-dev libv4l-dev
sudo apt-get install python-dev python-numpy
sudo apt-get install libtbb-dev
sudo apt-get install libqt4-dev libgtk2.0-dev
echo "Downloading x264"
wget ftp://ftp.videolan.org/pub/videolan/x264/snapshots/x264-snapshot-20120528-2245-stable.tar.bz2
tar -xvf x264-snapshot-20120528-2245-stable.tar.bz2
cd x264-snapshot-20120528-2245-stable/
echo "Installing x264"
if [ $flag -eq 1 ]; then
./configure --enable-static
else
./configure --enable-shared --enable-pic
fi
make
sudo make install
cd ..
echo "Downloading ffmpeg"
wget http://ffmpeg.org/releases/ffmpeg-0.11.1.tar.bz2
echo "Installing ffmpeg"
tar -xvf ffmpeg-0.11.1.tar.bz2
cd ffmpeg-0.11.1/
if [ $flag -eq 1 ]; then
./configure --enable-gpl --enable-libfaac --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libtheora --enable-libvorbis --enable-libx264 --enable-libxvid --enable-nonfree --enable-postproc --enable-version3 --enable-x11grab
else
./configure --enable-gpl --enable-libfaac --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libtheora --enable-libvorbis --enable-libx264 --enable-libxvid --enable-nonfree --enable-postproc --enable-version3 --enable-x11grab --enable-shared
fi
make
sudo make install
cd ..
echo "Downloading v4l"
wget http://www.linuxtv.org/downloads/v4l-utils/v4l-utils-0.8.8.tar.bz2
echo "Installing v4l"
tar -xvf v4l-utils-0.8.8.tar.bz2
cd v4l-utils-0.8.8/
make
sudo make install
cd ..
echo "Downloading OpenCV 2.4.3"
wget -O OpenCV-2.4.3.tar.bz2 http://sourceforge.net/projects/opencvlibrary/files/opencv-unix/2.4.3/OpenCV-2.4.3.tar.bz2/download
echo "Installing OpenCV 2.4.3"
tar -xvf OpenCV-2.4.3.tar.bz2
cd OpenCV-2.4.3
mkdir build
cd build
cmake -D CMAKE_BUILD_TYPE=RELEASE ..
make
sudo make install
sudo su
sudo echo “/usr/local/lib” >> /etc/ld.so.conf
sudo ldconfig
echo "OpenCV 2.4.3 ready to be used"

Special Thanks for the original writer. This is a little modified version of it

Install .deb file in Ubuntu

sudo dpkg -i .deb

This command may give error because the dependences may not be installed. If so,

sudo apt-get -f install





Note: Can applicable for google chrome, skype etc.

Customize Ubuntu Boot Menu

Grub-Customizer is the best GUI I found to customize Ubunutu boot menu. It allows you to select desired default boot or to boot previously booted OS.

 




sudo add-apt-repository ppa:danielrichter2007/grub-customizer
sudo apt-get update
sudo apt-get install grub-customizer