PTB beta “Broken Windows” release 2012-09-15


Psychtoolbox-3/Psychtoolbox-3@fde2c3f5 at GitHub

Most importantly this release adds 64-Bit Matlab support for MS-Windows and removes Octave support and Quicktime support for MS-Windows.

Release Highlights:


  • The runtime library requirements have changed: Now our mex files require the MSVC-2010 runtime libraries. Installers for these are contained in the Psychtoolbox/PsychContributed folders (vcredist.exe, vcredist_x64.exe).

  • The prehistoric PsychSerial() command has been removed. Use IOPort for serial i/o.

  • GNU/Octave support for MS-Windows completely removed. After over 3 years of availability on Windows, only about 117 of over 22000 MS-Windows users gave Octave a try - that’s only 0.5%, so i consider this a failure and declare defeat. If you want to continue using Octave 3.2.4 with Psychtoolbox on Windows, you must refrain from updating PTB 3.0.10 any further, or stick to PTB 3.0.9, otherwise the update will delete your Octave mex files. DownloadLegacyPsychtoolbox() always allows to downgrade to the unsupported v3.0.9 and then stick to that.

  • Apple Quicktime support for Windows finally completely removed. Now GStreamer is mandatory for multi-media functionality on Windows (Movie playback, movie creation, video capture, video recording). help GStreamer will tell you how to install it.

  • 64-Bit Matlab support for MS-Windows added. Limitations: At the moment, on 64-Bit Matlab, GStreamer must be installed for Screen() to work at all, even if you don’t use any multi-media functions. Eyelink() is unsupported with 64-Bit Matlab, as SR-Research doesn’t support 64-Bit Windows yet afaict. Datapixx support is missing, but will probably get added soon.

  • A new PsychTweak() command allows to control some parameters on how clocks are handled on MS-Windows. This allows to change the way broken clock hardware on MS-Windows is detected and handled. The defaults have been changed to be a bit more lenient to tolerate some brokeness in the latest processors on Windows.


  • 32-Bit Octave support on OSX removed, 64-Bit Octave 3.6 support added. Should work with Octave installed via the “HomeBrew” package manager.

  • Optional GStreamer support for 32-Bit Matlab on OSX added. Now you can use it on 10.6 Snow Leopard and later. Apple Quicktime is still the default on 32-Bit Matlab for OSX, the Screen('Preference') switches allow you to use GStreamer instead.

  • The PsychtoolboxKernelDriver on OSX now supports Intel integrated graphics cards as well.

I consider the 32-Bit PTB for OSX now on “live support”. I have one machine left for maintaining it. As long as that machine keeps working and is not getting upgraded to 64-Bit, i’ll keep the 32-Bit PTB for OSX alive.


  • Windowed window support and GUI window support now shows same level of functionality and behaviour as on OSX, e.g., PsychDebugWindowConfiguration is now fully useable.

All systems:

  • Movie playback performance and functionality improvements for GStreamer based movie playback engine. Some perf. improvements for videocapture engine, and basic GeniCam/GigE video capture support. The default behaviour and performance is the same, but some optional switches now allow to enable multi-threaded video decoding for some codecs, e.g., H264 and use of optimized texture upload methods for some movie formats. This can speed up playback of high framerate and high resolution videos considerably on high end machines with many cores and modern gpus. PlayMoviesDemo() has some new optional parameters pixelFormat and maxThreads which allow to enable these optimizations, e.g., on H264 video. E.g., a pixelFormat = 6 and maxThreads = 0 will use as many processor cores as available for video decoding. On Linux and OSX this can provide over six-fold speedup, on Windows the multi-threading seems to be mostly ineffective at the moment, probably due to some codec bugs on Windows.

  • Support for GL_TEXTURE_2D textures as render targets (e.g., Offscreen windows and use with TransformTexture) – For improved OpenGL interop with 3rd party OpenGL code like Horde3D. Non-power-of-two texture support. Mipmap filtering support and demos for efficient blurring via gpu accelerated resolution pyramids. The new BlurredMipmapDemo employs/demonstrates OpenGL mip-map filtering to use image resolution pyramids for fast blurring of images, e.g., for certain types of gaze contingent displays.

  • MOGL OpenGL support updated to support most new OpenGL-2.1 extensions up to the ones added in August 2012.

  • Various other improvements, cleanups and bug fixes i can’t remember.