GSVideo is fairly easy to install, just uncompress the library zip file and copy the gsvideo folder inside the libraries folder of Processing. However, GSVideo requires GStreamer to be installed on the computer as well, and depending on the platform, this could be a rather complicated task, at least at this point.

OSX

Installation on OSX is tricky. Right now it has to be done through macports, which means that it will be compiled from source. This post on the Processing forum details the steps to install GStreamer with macports.

Windows

There are pre-compiled binaries for Windows available here. These binaries also require the GTK+ library installed. There are different GTK+ installation packages available for windows. I tested the latest releases available from these two sites:

Glade/Gtk+ for Windows
GTK+ and The GIMP installers for Windows

Note that the GTK+ individual packages from the GTK+ project site don't seem to work with GStreamer.

Unfortunately, the windows binaries for windows are not updated very often. The binary packages from the source snapshots are not updated often either. There is the OABuild project which allows to compile GStreamer, GTK+, glib and ffmpeg from the latest source code using MS Visual Studio.

The GSCapture object uses the directshow wrapper plugin, but the one included with the latest gst-plugins-bad package available (0.10.6) is not the most up-to-date and doesn’t work with many webcams. Here is the dll of the updated directshow wrapper that fixes these compatibility issues. Just download it and copy where the gstreamer plugins are installed, usually in “C:\Program Files\Common Files\GStreamer.10\lib\gstreamer-0.10″.

Linux

Since GStreamer is developed natively on Linux, this is the platform where the installation is the easisest. In most distributions, GStreamer cames preinstalled as the default multimedia library.

On some versions of Ubuntu, GSVideo doesn't work unless the package libgstreamer0.10-dev is installed as well.