Ubuntu – how to install opencv4.0 on 18.10

compilingopencvsoftware installation

I have been trying to install opencv4.0.1 on ubuntu for a few weeks now. I have followed the opencv installation instructions
and I am able to make and compile the library, yet after installation, pkgconfig still cant find the library, and when I try to build programs, I get things like missing library errors.

$ pkg-config --cflags opencv
Package opencv was not found in the pkg-config search path.
Perhaps you should add the directory containing `opencv.pc'
to the PKG_CONFIG_PATH environment variable
No package 'opencv' found

Best Answer

According to this issue, OpenCV dropped support for pkg-config. However, this can be added as follows:

Configure

When you run cmake add the additional parameter -D OPENCV_GENERATE_PKGCONFIG=YES e.g.

cmake -D CMAKE_BUILD_TYPE=Release -D OPENCV_GENERATE_PKGCONFIG=YES -D CMAKE_INSTALL_PREFIX=/usr/local ..

Then make and sudo make install as before.

Test

Use the name opencv4 instead of just opencv e.g.

pkg-config --cflags opencv4

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Ubuntu – How to build and install latest SimpleScreenRecorder from git

I got this working with some help from the developer. First, the dev said that my version of ffmpeg was fine. He also clarified that if the output of simple-build-and-install includes 'Configuring 32-bit GLInject library' (i.e., if you manage to get to that point in the build process) it means that the 64-bit build portion is OK. That means the solution is to use his symlink workaround.

Below are my exact steps.

Note that I skipped one step recommended by the developer. I skipped it because the target link already existed and I wanted to try it without changing that link. (It worked.)

sudo apt-get install build-essential pkg-config qt4-qmake libqt4-dev libavformat-dev libavcodec-dev libavutil-dev libswscale-dev libasound2-dev libpulse-dev libgl1-mesa-dev libx11-dev libxext-dev libxfixes-dev g++-multilib ia32-libs
cd /workspaces/ (or any path you choose - see note below)
git clone https://github.com/MaartenBaert/ssr.git (in my case the project path is /workspaces/ssr/)
sudo mkdir /usr/lib32/fglrx/
cd /usr/lib/i386-linux-gnu/
sudo ln -s libGL.so.1 /usr/lib32/fglrx/libGL.so  # only for proprietary AMD drivers!
# SKIP: sudo ln -s fglrx/libGL.so /usr/lib32/libGL.so    # only for proprietary AMD drivers!
sudo ln -s libGLU.so.1 libGLU.so
sudo ln -s libX11.so.6 libX11.so
sudo ln -s libXext.so.6 libXext.so
sudo ln -s libXfixes.so.3 libXfixes.so
sudo ldconfig
cd /path/to/ssr (will be the ssr directory under `/workspaces/` in my example)
$ ./simple-build-and-install

The final result:

Running post-install script ...
Done.

So I ran it and it didn't crash! :-) That was the first big change.

Then I tested it. I used all default settings. And the recorded screencast looked and sounded really good!!! I'm extremely pleased. The software is easy to use and it works great.

Ubuntu – How to install termite

Over here is an install script, that nicely explains all dependencies and stuff, I'll just copy that for you ;)

Install dependencies

sudo apt install -y g++ libgtk-3-dev gtk-doc-tools gnutls-bin \
    valac intltool libpcre2-dev libglib3.0-cil-dev libgnutls28-dev \
    libgirepository1.0-dev libxml2-utils gperf build-essential

Get and install vte-ng

git clone https://github.com/thestinger/vte-ng.git
echo export LIBRARY_PATH="/usr/include/gtk-3.0:$LIBRARY_PATH"
cd vte-ng && ./autogen.sh && make && sudo make install
cd ..

Get and install termite, and setup

git clone --recursive https://github.com/thestinger/termite.git
cd termite && make && sudo make install
sudo ldconfig
sudo mkdir -p /lib/terminfo/x
sudo ln -s /usr/local/share/terminfo/x/xterm-termite /lib/terminfo/x/xterm-termite

Voila, this should be it ....

Best Answer

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Ubuntu – How to build and install latest SimpleScreenRecorder from git

Ubuntu – How to install termite

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