PTB beta released 4.9.2010 (SVN Revision 1783)


This summarizes all new beta features from 6.6.2010 up to 4.9.2010. The list of improvements is likely incomplete as always. For detailed logs, click this link.

This update contains a couple of bug fixes and minor improvements. Most interesting should be the improvements to the Eyelink toolbox by Frans Cornelissen.

  • Improvements and cleanup to many demos by Frans Cornelissen. Frans also enabled the video feed from the Eyelink eye camera during tracker calibration by default, so the subjects eye can be monitored during calibration procedures. The PsychHardware/EyelinkToolbox/ folder contains a file “compatibility” (help compatibility) with information on what has changed in this release of the Eyelink toolbox and how to restore the old behaviour if you don’t like the eye camera video feed to be displayed.

PsychPortAudio sound driver

  • Bugfix when used with Microsoft Windows Vista or Windows-7 on fast multi-core machines (e.g., has only been observed on a 8 core, 2.7 Ghz PC running Windows-7): Under certain circumstances the driver may falsely report your computers clock to be broken (“Time going backwards” warning) and switch to a low resolution backup clock. This is now fixed. The same fix applies to Screen and IOPort, although it was very unlikely to encounter the bug when using those mex files.

Improvements and bug fixes to Screen and other drawing functions – The Visuals

  • Updates to help texts for some functions.
  • The PsychtoolboxKernelDriver for OS/X on IntelMacs with ATI GPU’s has been refined (help PsychtoolboxKernelDriver). Now provides even more precise visual onset timestamping and removes a constant 0.4 - 0.7 msecs (depending on videomode) bias in the timestamps. Datapixx measurement confirms our timestamps are now spot-on on the two tested ATI GPU’s, a Mobility Radeon X1600 and a FireGL-V3700
  • Improvements to procedural gabor- and sinegrating rendering. Allow to specify a global contrast scaling factor as proposed by Xiangrui Li.
  • CreateProceduralSineGrating(): Add optional support for drawing procedural sine gratings with a circular aperture of selectable radius.
  • PsychImaging: Add new stereo mode 'InterleavedColumnStereo' for column interleaved stereo displays, e.g., for driving auto stereoscopic displays based on lenticular sheet lenses or parallax barriers. ImagingStereoDemo(101) demonstrates this.

Misc stuff

  • Some improvements to display calibration, gamma correction and color handling routines by David Brainard’s lab. Also improvements to the PR-650 photometer support.
  • Some improvements to general toolbox routines by Diederick Niehorster.
  • BalanceFactors: Speed optimization by David Fencsik. BalanceTrials() - New function for balancing a set of factors, contributed by David Fencsik.