Psychtoolbox interfaces between Matlab or Octave and the computer hardware. The
PTB core routines provide high performance 2D and 3D graphics with the highest
color and luminance precision, timing precision and control. This both on standard
displays, as well as with special visual stimulators, and with High Dynamic Range
displays, and with a wide variety of Virtual/Augmented Reality devices. They expose
raw OpenGL commands, support video playback and capture, as well as low-latency
precisely timed audio playback and capture. They facilitate the collection of observer
responses with high timing precision via various input modalities like keyboard, mouse,
game controllers, multi-touch touch screens, response boxes, gaze trackers, and digital /
analog i/o equipment. Ancillary helper routines support common needs like color space
transformations, calibration, and psychometric procedures like, e.g., the QUEST threshold
seeking algorithm and others.
Various 3rd party frameworks and higher level toolboxes are built on top of Psychtoolbox
to make implementation of research data collection especially easy in specific sub-domains
of neuroscience. For beginners or certain domains there also exist user friendly 3rd party
graphical user interfaces, e.g., PsyBuilder.
You can also run some of your Psychtoolbox studies online, via VPixx Labmaestro service under
https://vpixx.com/products/labmaestro-packngo.
Psychtoolbox has many active users, an active forum, and is widely
cited. The current version supports at least Matlab R2024b on Linux, Windows
and macOS, and Octave 5 and later on Linux, and Octave 7.3 on Windows, and Octave 9 on macOS.
Psychtoolbox 3.0.19.16 “Last free dessert” was released at 20th November 2024.
The complete development history can be found in our GitHub repository.
The release tag is “3.0.19.16”, with the full tree and commit logs under the URL:
https://github.com/Psychtoolbox-3/Psychtoolbox-3/tree/3.0.19.16
This Psychtoolbox release was sponsored by Mathworks under the year 2024 contract
for establishing Matlab R2024b compatibility on Ubuntu 24.04 Linux and Windows 10.
Highlights:
-
None. This is a release with small fixes and tweaks, based on compatibility
testing of Psychtoolbox with Ubuntu Linux 24.04.1-LTS and MS Windows-10 22H2
with Matlab R2024b under the Mathworks 2024 contract which requires at least
one Psychtoolbox release that is compatible with R2024b under Linux and Windows.
As such, no compatibility testing was performed wrt. macOS, apart from quick
spot testing with R2024b, as testing on macOS was not part of the paid contract,
and the contract pays way too little to cover any non-mandatory work.
The total work time spent on R2024b testing and refinement was 42 hours.
No compatibility issues were found with R2024b, compared to R2024a, iow.
no regressions. All improvements in this release are for fixing / working
around Microsoft Windows bugs or flaws, or AMD and NVidia graphics driver
bugs on Windows. And some small tweaks and enhancements.
All:
-
RenderDemo: Add missing BackupCluts to not annoy the user. Restore the lut’s
at the end of the demo, so display doesn’t look “milky” and dull.
-
FlipTimingWithRTBoxPhotoDiodeTest: Let audio card select its preferred sample rate.
Some Some recent sound chips don’t like our hard-coded 44100 Hz, so let them
choose their preferred rate.
-
PlayMoviesDemo: Cleanup web movies offering a bit.
-
PsychImaging: Some doc update wrt. Intel 10 bpc support on Ubuntu 22.04+.
Linux:
- Psychtoolbox was extensively tested against Matlab R2024b, under Ubuntu 24.04.1-LTS
Linux with AMD Polaris and Intel Kabylake graphics, also in dual-gpu configurations
on a dual-gpu hybrid graphics Laptop.
Windows:
-
Psychtoolbox was extensively tested against Matlab R2024b, and lightly tested
against Octave 7.3, both under MS-Windows 10 R22H2 with primarily AMD graphics,
and spot checked with NVidia graphics.
-
MultiWindowLockStepTest: Fix failure in default dual-window 10/20 seconds async
flip case on MS-Windows 10, due to interaction with an OpenGL quirk.
-
DrawManuallyAntiAliasedTextDemo: Add workaround for AMD OpenGL graphics driver
bug on Windows-10. Ditto for TextToStuffColorMismatchTest.m.
Enjoy!
Psychtoolbox 3.0.19 update “Last free lunch” was released at 3rd November 2024.
The complete development history can be found in our GitHub repository.
The release tag is “3.0.19.15”, with the full tree and commit logs under the URL:
https://github.com/Psychtoolbox-3/Psychtoolbox-3/tree/3.0.19.15
Highlights:
- None. Only bug fixes for various 3rd party components, and small improvements.
All:
-
Change enumeration order of video capture devices. This should avoid
selection of suboptimal capture devices by preferring more optimal ones,
especially on modern Ubuntu 22.04-LTS and later Linux distributions, which
often choose the new but immature pipewiresrc as video source plugin for a
camera instead of the old and proven/mature more optimal v4l2src as video
source. Specifically we hope to avoid VideoRecordingDemo.m problems like
the ones encountered in the following thread:
https://psychtoolbox.discourse.group/t/codecs-in-videorecordingdemo-not-working-on-linux/5441
-
PsychImaging: Fix HDR mode with types of PsychColorCorrection() that involve
lookup tables and only use one color correction operation in total. E.g,
standard LUT based correction, 3D LUT based correction or application of
per-pixel gain matrices. See:
https://psychtoolbox.discourse.group/t/best-approach-for-gamma-correction-in-hdr10/5515
-
CI release scripts: Disable building of .mltbx files for releases for now.
The current approach contributed by Mathworks team is broken. It includes the
whole Psychtoolbox-3 tree for some utterly unclear reason, although the project
file only specified the Psychtoolbox/ subfolder. Worse, it adds toolbox folders
to the Matlab path in randomized (!?!) order, so our carefully selected ordering
of MatlabWindowsFilesR2007a/ folder wrt. PsychBasic folder gets screwed up and mex
files can’t be found on MS-Windows anymore. Even worse, if SetupPsychtoolbox() fixes
it, then the Matlab Add-On Manager undos the fix every single time Matlab restarts!
This leads to issues like the following linked one:
https://psychtoolbox.discourse.group/t/problem-with-screen-function-ptb-just-installed/5451/9
Apart from that, the Add On manager doesn’t allow toolbox updates, and doesn’t
set things like the Matlab Java path, doesn’t deal with GStreamer etc. It has
zero benefit for our users, but is a source of hazarads and extra support overhead.
Drop it.
-
Add Psychtoolbox/PsychBasic/PsychPlugins/ to the search path for dynamic shared
libraries for all operating systems, so PTB specific plugin libraries can be found
during mex file load time.
Linux:
-
Psychtoolbox was built and tested against Matlab R2024a and Octave 5.2 and later.
-
PsychImaging: Update ‘EnableNative16BitFramebuffer’ help text for year 2024.
-
Screen: Fix Vulkan display backend support with Mesa versions 23.3 and later
and thereby for Ubuntu 24.04-LTS and later. The same problem that affected the
Broadcom VideoCore 6 of the RaspberryPi 4 and later under Mesa 23.3 now affects
at least Intel and AMD under Mesa 24.0 with Ubuntu 24.04.0-LTS.
It appears a slightly broken GL_EXT_direct_state_access implementation
in Mesa was introduced in Mesa 23.3 and later. Work around this in an effective
and safe way.
-
PsychVulkan: Add workaround against an AMDVLK bug that causes crash if the used
Vulkan display monitor has more than 64 video modes. A proper fix, especially
for multi-display setups, can only be done in a future AMDVLK driver from AMD’s
Vulkan team, but for single display stimulation this workaround should prevent
crashes and problems, and on some multi-display setups things may still work
with a sprinkle of dumb luck - no guarantees for multi-display though!
Note that the AMDVLK driver is only used on AMD gpu’s if a color depth of more
than standard 8 bpc (aka “deep color”) or HDR-10 display mode is requested. For
other Vulkan use cases, the high quality Mesa radv Vulkan driver is used, which
does not suffer such a problem. For context see:
https://psychtoolbox.discourse.group/t/vulkan-breaks-with-stack-smashing-detected-terminated/5501
-
XOrgConfCreator: Adapt to Ubuntu 24.04-LTS changes in /dev/dri/card enumeration.
This broke hybrid graphics laptop detection, at least on three single gpu
laptops with AMD gpu’s. It reported a dual-gpu config when there was not any.
Since Ubuntu 24.04-LTS, or more likely with a recent Linux 6.8 kernel shipping
in both Ubuntu 24.04-LTS and in Ubuntu 22.04.5-LTS with HWE stack, the first
(and only) gpu on a single gpu machine now has a /dev/dri/card1 device file,
instead of a /dev/dri/card0 device file, ie. device file indexing now starts
at 1 instead of 0. On multi-gpu machines, the second gpu is now associated
with /dev/dri/card2 and so on. This broke some hard-coded assumptions about
0-based device numbering. We now use a more robust detection logic for hybrid
gpu detection. The fix was successfully tested on single-gpu AMD and Intel
graphics machines, and on a dual-gpu Intel + AMD laptop for each gpu and in
prime render offload mode.
-
Add braces for NetWM reporting to make compiler happier. It caused a weird
problem in the Screen mex build for Matlab, in which the “PTB-INFO: …” lines
about the used flip timestamping mechanism are not printed! No clue why, looks
like some compiler bug, but adding the - technically not needed - braces fixes
it.
Windows:
-
Psychtoolbox was built and lightly tested against Matlab R2024a and Octave 7.3.
-
VideoRecordingDemo.m: Remove special case MS-Windows path. It does not seem to
be as necessary anymore with the future default MediaFoundation path for capture
and recording. Also added some cleanups and ability to specify video capture
device as argument.
macOS:
- Psychtoolbox was built and tested against Matlab R2024a and against Octave 9.2
from HomeBrew.
Enjoy!
Psychtoolbox 3.0.19 update “Sommerloch” was released at 11th August 2024.
As usual, the complete development history can be found in our GitHub repository.
The release tag is “3.0.19.14”, with the full tree and commit logs under the URL:
https://github.com/Psychtoolbox-3/Psychtoolbox-3/tree/3.0.19.14
Highlights:
All:
-
Screen('DrawDots'): Only apply a margin to non-square dot types.
Only round dots get trimmed in the fragment shader, and so dot_type=4
was left with too much padding from the vertex shader. Bug fix contributed
by Alex Forrence @aforren1
-
Python extensions built from this release onwards should also work with
NumPy 2.x in addition to NumPy 1.x. Changes contributed by Eric Larson.
Linux:
-
Psychtoolbox was built and tested against Matlab R2024a.
-
Undo Screen('OpenMovie') compatibility fix for Ubuntu 24.04-LTS, of
using pipewiresink as audio sink. While this does fix the pulseaudio bugs
of delayed playback (see Psychtoolbox 3.0.19.12), the pipewiresink plugin
itself, as shipping in Ubuntu 24.04-LTS / GStreamer 1.24, has its own bugs,
which are worse and impact more frequent use cases, e.g., seeking, change
of playback speed, reverse playback, and instabilities or hangs at end of
playback for some common movies. Iow. use of pipewiresink causes regressions.
See forum bug report here:
https://psychtoolbox.discourse.group/t/10-second-delay-with-with-gst-state-change-async/3924
GStreamer folks know about the problem but there ain’t a solution yet.
As of this release, the pipewiresink can still be used as an active opt-in,
accepting other potential types of audio playback problems, and if opted in,
should fix the following issue on Ubuntu 24.04-LTS and later, and other
distributions that use Pipewire as desktop sound server and have an outdated
buggy Pulseaudio 16 installation, instead of the more recent Pulseaudio 17.
See the following issue for this bug, which is luckily not encountered often:
https://github.com/Psychtoolbox-3/Psychtoolbox-3/issues/814
On unfixed affected systems (mostly Ubuntu 22.04-LTS), if there is
a notable time delay between Screen('OpenMovie') and start of
video+audio playback via Screen('PlayMovie'), then the movie
playback will freeze after displaying the 1st video frame for the
duration of that delay between OpenMovie and PlayMovie, then
continue. Problem didn’t exist in earler Linux distributions like
Ubuntu 20.04-LTS and is fixed by this bug fix for later distros like
Ubuntu 24.04-LTS from April 2024.
The use of pipewiresink can be enforced as workaround by specifying the
following string as ‘movieoptions’ parameter in Screen('Openmovie', ...);
‘AudioSink=pipewiresink’.
-
RaspberryPi now also allows GetSecs clock selection, like the Intel
variants do since a few releases.
Windows:
macOS:
-
Psychtoolbox was built and tested against Matlab R2024a and against
Octave 9.2 from HomeBrew.
-
SetupPsychtoolbox(): Try to fix it properly for macOS with xattr calls.
Skip xattr calls for .mltbx installed files via Matlab Add-On explorer,
as those already have their quarantine flags removed.
For other (zip file) install locations, handle blanks/spaces in the
installation path.
Also some output text cleanups and fixes. Tested with .mltbx and zip file
path install on path with spaces etc. Lets hope this goes better.
Enjoy!