GStreamer

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GStreamer - Installation instructions for the GStreamer media framework.

Psychtoolbox in all versions for GNU/Linux, and in (future) 64 bit
versions for Mac OS/X and MS-Windows uses the GStreamer multi-media
framework for all multi-media related operations.

All movie playback, movie creation, video capture and video recording
operations are based on GStreamer. These functions won't work without a
working GStreamer installation on your system.

You will need at least version 0.10.24 of GStreamer, but we recommend to
use the latest available versions, as not all Psychtoolbox features are
fully supported by version 0.10.24. Especially video capture, video
recording and movie creation may be limited in functionality or
performance if you don't use a recent version of GStreamer.

By default, the 32-bit versions of Psychtoolbox for Windows and MacOS/X
use Apple's Quicktime for those operations, so GStreamer isn't strictly
needed there. You can however use GStreamer (once installed) instead of
Quicktime if you add the following command to the top of your experiment
script, before any other Screen() command:

This uses GStreamer instead of Quicktime for movie playback:
Screen('Preference', 'OverrideMultimediaEngine', 1);

This uses GStreamer instead of Quicktime for video capture or video
recording:

Screen('Preference', 'DefaultVideocaptureEngine', 3);

So what's the deal with GStreamer?

GStreamer (Webpage web: http://www.gstreamer.net ) is a free software /
open-source multimedia framework. The summary on its webpage summarizes
it as follows:

"GStreamer is a library for constructing graphs of media-handling
components. The applications it supports range from simple Ogg/Vorbis
playback, audio/video streaming to complex audio (mixing) and video
(non-linear editing) processing.

Applications can take advantage of advances in codec and filter
technology transparently. Developers can add new codecs and filters by
writing a simple plugin with a clean, generic interface.

License: GStreamer is released under the LGPL. The 0.10 series is API and
ABI stable."

In summary, GStreamer is for the free software world what Quicktime is
for Apple's "walled garden". It is used a the standard media framework
for many (most?) Linux desktop systems, netbooks, and MeeGo, Web-OS (and
also Android) based tablets and Smartphones. It is also used on many
Linux based embedded devices.

GStreamer itself is very high performance, mature and stable.
Psychtoolbox's support however is in its early stage, so don't be
surprised if you find bugs or limitations. Report them on the forum
instead, so we can fix them.

Installation instructions:

GNU/Linux: Any half-way recent Linux distribution will include support
for GStreamer in its package management system, so you can easily install
it via the software management tool of your system.

You will need at least the core GStreamer runtime and the gstreamer-base
set of plugins. A simple way to get GStreamer at least on Ubuntu Linux is
to install the "rhythmbox" or "totem" multimedia-players. You may need to
install additional plugin packages to play back all common audio- and
video file formats. Especially video recording or movie creation with
high quality will require recent versions of the additional plugin
packages gstreamer-bad, gstreamer-good, gstreamer-ugly. These are not
always installed by default and may need you to specifically request them
for installation.

E.g., a "sudo apt-get install totem" typed into a terminal window,
followed by your administrator password, should do the trick. Most likely
this isn't needed though, as you likely already have GStreamer installed
if you ever used to playback any multimedia content on your Linux system.

MS-Windows:

We currently provide GStreamer support on Windows with 32-bit Matlab V7.4
(R2007a) and later, as well as on Octave. In fact, a fully working GStreamer
installation is mandatory for Psychtoolbox to work on Octave for Windows,
otherwise the Screen() function will fail to work at all, regardless if
you use multi-media functions or not. For Matlab, GStreamer is still
optional. We don't intend to ever provide GStreamer support for Matlab
versions older than Version 7.4.

The current Windows implementation is a sneak-preview for people interested in
testing and giving feedback, not neccessarily for the average user.

You can download and run a standard MS-Windows setup.exe installer from:

web: http://code.google.com/p/ossbuild/

For best results, you'd currently (beginning June 2011) choose this
one or any later version: "GStreamer-WinBuilds-GPL-x86-Beta04-0.10.7.msi"
The current download link is:

<http://ossbuild.googlecode.com/files/GStreamer-WinBuilds-GPL-x86-Beta04-0.10.7.msi>

If you are a fan of stable versions, we recommend this one:
"GStreamer WinBuilds v0.10.6, LGPL (x86)"

However, some features may be disabled or limited with such an older
version.

IMPORTANT: Users of Octave under Windows must not only install GStreamer
on their system. They must also delete (or rename) the file iconv.dll
that comes with Octave. This file is incompatible with a iconv.dll of the
same name provided by GStreamer. On Octave 3.2.4 you'd delete, rename or
move away the following file:

C:\Octave\3.2.4_gcc-4.4.0\bin\iconv.dll

For example, you could rename it into

C:\Octave\3.2.4_gcc-4.4.0\bin\iconv_DISABLED.dll

Mac OS/X:

No support for GStreamer yet. Stay tuned!