View source for User:Donnguyen/Building and using Qt5GStreamer on Windows

This document guides you through the process of building, installing, and using Qt5GStreamer on Windows.
=Setting up dependencies=
==Boost==
Boost is required to build and use Qt5GStreamer.  Set up is rather simple.  Download the .zip from the [http://www.boost.org/ boost.org website], extract it, and set the environment variable BOOST_ROOT  to the root directory of the boost installation(C:\boost\boost_1_63_0).  Verify this is correctly set up by opening a command prompt and typing <code>dir %BOOST_ROOT%\libs</code>.  You should see a bunch of directories.

==Gstreamer==
Download and install at least the runtime and development files from the [https://gstreamer.freedesktop.org/ Gstreamer web site].  Set both environment variables GSTREAMER_ROOT_X86 and GSTREAMER_1_0_ROOT_X86 to the installation directory(C:\gstreamer\1.0\x86).  Add %GSTREAMER_ROOT_X86%\bin to your PATH.  Verify you have this set up correctly by opening a command prompt and type <code>gst-launch-1.0 -h</code>.  You should see the usage output from the gst-launch command.

==Cmake==
You will need CMake to configure and build Qt5GStreamer.  Download and install it from the [https://cmake.org/ CMake website].  {{Warning|2=Warning|1=If you choose to add cmake to your path (more convenient), make sure you add it AFTER %QTDIR%\bin.  The cmake bin directory has qt .dll's that will likely cause conflicts, so I would recommend making it the last item in your path just to be safe.}}  
If chose to add cmake to your PATH, verify it is correctly set up by opening a command prompt and typing <code>cmake -version</code>.  You should see the version of cmake printed on the screen.

=Building Qt5GStreamer=
Using the default install path of "C:/Program Files (x86)/QtGStreamer" can cause problems because of the special characters in the path, and special permissions required, so we'll install it to C:\QtGStreamer.
{{Warning|2=Important|1=Make sure you have cmake set up with Qt Creator.}}
Steps:
#Set environment variable QTGSTREAMER_ROOT to C:\QtGStreamer
#Download source via: <code>git clone https://github.com/GStreamer/qt-gstreamer</code>
#Start Qt Creator and open CMakeLists.txt.  Switch to Projects and edit the Build Settings.  Under the CMake section, edit CMAKE_INSTALL_PREFIX and set it to %QTGSTREAMER_ROOT%.  Edit QT_VERSION and set it to 5.  Click on "Apply Configuration Changes".  Under Build Steps, click on Details, and select the target "install".  
#Build the project.
#Finally, add %QTGSTREAMER_ROOT%\bin to PATH to complete the set up.  
Verify Qt5GStreamer is properly built and installed by opening a command prompt and typing <code>dir %QTGSTREAMER_ROOT%\bin</code>.  You should see some .dll files starting with Qt5G.

=Using Qt5GStreamer=
If you're going to use cmake, you're all set.  If you want to use qmake, there are additional steps to set up.
==Installing and setting up pkg-config==
===Installing pkg-confg===
There are several ways to set up pkg-config.  Some set-ups are complicated, and some don't work :-/  Fortunately, I found a simple set up that works.  Download pkg-config-lite from https://sourceforge.net/projects/pkgconfiglite/files/
Unzip, and add the bin directory to your path.  Verify this is set up correctly by opening a command prompt and typing <code>pkg-config --help</code>.  You should see the help for pkg-config.  

===Setting PKG_CONFIG_PATH===
Set PKG_CONFIG_PATH to %GSTREAMER_ROOT_X86%\lib\pkgconfig;%QTDIR%\lib\pkgconfig;%QTGSTREAMER_ROOT%\lib\pkgconfig.  Verify pkg-config can find Qt5Streamer-1.0 by opening a command prompt and typing <code>pkg-config --cflags Qt5GStreamer-1.0</code>.  You should not see any errors.  If you see errors, you will need to resolve them.  If you're using the MSVC compiler, check the MSVC section below.

==Using Qt5GStreamer via PKGCONFIG in .pro file==
Add the following to .pro file:
<syntaxhighlight lang="qmake">
CONFIG += link_pkgconfig
PKGCONFIG += Qt5GStreamer-1.0 Qt5GStreamerUi-1.0
QT += widgets
INCLUDEPATH += $$(BOOST_ROOT)
</syntaxhighlight>

Try opening the example .pro included with the qt-gstreamer source, make some edits, and try to build it.  If you can build and run the example, you're all done.

==MSVC hack==
Edit two files under %QTGSTREAMER_ROOT%\lib\pkgconfig.
Qt5Glib.pc and Qt5GStreamerUi.pc: comment Qt5Core and Qt5Widgets.  pkg-config can't find them because they don't exist for MSVC.

=Troubleshooting=
As a general rule, don't mix 32 and 64 bit, debug and release, libraries.