Installing

The debian package includes the core library, its python bindings and some API level 2 python code. The python part is installed “globally” into /usr/lib/python3/dist-packages/

Note

LibValkka comes precompiled and packaged for a certain ubuntu distribution version. This means that the compilation and it’s dependencies assume the default python version of that distribution. Using custom-installed python versions, anacondas and whatnot might cause dependency problems.

A. Install using PPA

the preferred way

For recent ubuntu distributions, the core library binary packages and python bindings are provided by a PPA repository. Subscribe to the PPA repo (do this only once) with:

sudo apt-add-repository ppa:sampsa-riikonen/valkka

Install with:

sudo apt-get update
sudo apt-get install valkka

When you need to update valkka, do:

sudo apt-get update
sudo apt-get install --only-upgrade valkka

B. Install using releases

if you don’t like PPAs

You can download and install the required .deb packages “manually” from the releases page

sudo dpkg -i Valkka-*.deb
sudo apt-get install -fy

The last line pulls the dependencies.

Repeat the process when you need to update.

C. Compile yourself

the last resort

If you’re not using a recent Ubuntu distro and need to build libValkka and it’s python bindings yourself, please refer to the valkka-core github page.

Test your installation

Test the installation with:

curl https://raw.githubusercontent.com/elsampsa/valkka-examples/master/quicktest.py -o quicktest.py
python3 quicktest.py

Numpy

Valkka-core binaries has been compiled with the numpy version that comes with the corresponding Ubuntu distro, i.e. the numpy you would install with sudo apt-get install python3-numpy.

That version is automatically installed when you install valkka core with sudo apt-get, but it might be “shadowed” by your locally installed numpy.

If you get errors about numpy import, try removing your locally installed numpy (i.e. the version you installed with pip install --user).

Install the testsuite

First, install some debian packages:

sudo apt-get install python3-pip git mesa-utils ffmpeg vlc

some of these will be used for benchmarking Valkka agains other programs.

The testsuite and tutorials use also imutils and PyQt5, so install a fresh version of them locally with pip:

pip3 install --user imutils PyQt5 PySide2 setproctitle

Here we have installed two flavors of the Qt python bindings, namely, PyQt5 and PySide2. They can be used in an identical manner. If you use PyQt5, be aware of its licensing terms.

Finally, for tutorial code and the PyQt test suite, download valkka-examples with:

git clone https://github.com/elsampsa/valkka-examples

Test the installation with:

cd valkka-examples
python3 quicktest.py

and you’re all set.

When updating the python examples (do this always after updating valkka-core), do the following:

git pull
python3 quicktest.py

This checks that valkka-core and valkka-examples have consistent versions.

In the case of a numerical python version mismatch error, you are not using the default numpy provided by your Ubuntu distribution (from the debian package python3-numpy). Remove the conflicting numpy installation with pip3 uninstall or setting up a virtualenv.

Next, try out the PyQt test/demo suite or learn to program with the tutorial.

GTK

If you wan’t to use GTK as your graphical user interface, you must install the PyGObject python bindings, as instructed here, namely:

sudo apt-get install python-gi python-gi-cairo python3-gi python3-gi-cairo gir1.2-gtk-3.0

OpenCV

Install with:

pip3 uninstall opencv-python
sudo pip3 uninstall opencv-python # just in case!
sudo apt-get install python3-opencv

The first one deinstall anything you may have installed with pip, while the second one installs the (good) opencv that comes with your linux distro’s default python opencv installation.

Development version

As described above, for the current stable version of valkka-core, just use the repository.

For the development version (with experimental and unstable features) you have to compile from source. You might need to do this also for architectures other than x86.

Follow instructions in here.