As a little pre-christmas present 
for you:
Psychtoolbox 3.0.20 “Appletizer” was released at 13th December 2024, at least
in some time zone. Hopefully Friday 13th will bring us luck instead of horror 
.
The complete development history can be found in our GitHub repository.
The release tag is “3.0.20.0”, with the full tree and commit logs under the URL:
https://github.com/Psychtoolbox-3/Psychtoolbox-3/tree/3.0.20.0
This is the first release with beta quality macOS Apple Silicon Mac support
for native use on Apple Macintosh computers with 64-Bit ARM Apple proprietary
M1, M2, M3, … SoC’s. 
We thank the labs of Keith Schneider at the University of Delaware and of
Bas Rokers at NYU Abu Dhabi for substantial sponsorship to push Apple
Silicon support over the finish line. 
Effective immediately, the Psychtoolbox 3.0.19 series has now reached end of life.
No improvements, bug fixes or user support will be provided for Psychtoolbox 3.0.19
or earlier versions of Psychtoolbox.
Compatibility changes wrt. Psychtoolbox 3.0.19.16:
-
Psychtoolbox 3.0.20 and later on Apple macOS and Microsoft Windows
will require purchase of a paid software license key, once the
initial time-limited free trial period after first installation and
use has expired. Psychtoolbox will not work after the end of the trial
period without such a paid license key. The Psychtoolbox variants for
Linux on Intel processors and 32-Bit RaspberryPi will remain free to
use for the time being.The free time-limited trial period will last until the launch of
our new online shop, ie. until you will be able to buy software
license keys. The estimated date of launch, and end of the free
trial, will be likely around early to mid January 2025.Follow the news on http://psychtoolbox.org and on our Discourse
user forum or our social media feeds @psychtoolbox on X / Twitter,
Psychtoolbox (@psychtoolbox@neuromatch.social) - Neuromatch Social on Mastodon, or on BlueSky
@psychtoolbox.bsky.social for announcements of the launch of the
software license key sale early in the year 2025, or go to
https://psychtoolbox.net to find out how to buy a key, once sales
has started.
Highlights:
-
Initial “Beta” Apple Silicon support for running Psychtoolbox on macOS
for Apple Silicon Macs. Psychtoolbox can now be used with native Octave
and Matlab for Apple Silicon ARM Macs, ie. machines with Apple M1,
M2, M3, M4, … SoC’s. Most basic functionality should work reasonably
well, and substantially better than when using older Psychtoolbox
versions via Matlab for IntelMacs, which had various severe limitations
which would make them painful to use and deeply hazardous for any real
data collection! This versions Apple Silicon support was tested by myself
on a Apple MacBookPro early 2023 with 16 inch Liquid Retina XDR display
and Apple M2 Pro SoC under macOS 14.5 Sonoma with 64-Bit native Octave 9.2
from HomeBrew, and with Matlab R2024a and with Matlab R2024b. It was also
more lightly tested by others on a similar 16 inch MacBookPro late 2023 with
M3 Pro SoC under the macOS 15.2 Sequoia beta under Matlab R2024b, and a
MacBookAir 2020 with M1 SoC, and a Mac Studio 2023 M2 Ultra and MacBookAir
M3 13 inch early 2024, the latter two with macOS 15.2 beta and Matlab R2024b.
Thanks to our volunteer testers.While surely some bugs or limitations still exist, this should be a first good
release for basic use and evaluation.Known limitations are lack of frame-sequential stereo support in stereo modes
1 and 11, Screen Async flips, ie. subfunctions ‘AsyncFlipBegin’, ‘AsyncFlipEnd’
and ‘AsyncFlipCheckEnd’ are unsupported. Certain glitches in frame presentation
timing are still observed under certain conditions at least on macOS 14, e.g.,
stalls / short freezes after the stimulus image was static for a while, e.g,
observable with MouseTraceDemo if not moving the mouse for a while. These may
also trigger printing of some warning messages into the Matlab or Octave Window
about “…Failed to retrieve … stimulus onset timestamp! Timed out.”. It is
not yet clear if these issues are still present on macOS 15 Sequoia as well,
testing to be done. These remaining timing glitches are almost certainly due to
Apple macOS operating system bugs, which will either need proper fixing by Apple,
or need invention of new creative workarounds on our side, if that is needed and
possible.Apples “ProMotion” display mode on some builtin Retina displays, e.g., of the
MacBookPro models, and variable refresh rate modes in general, are not supported
and will cause more erratic behaviour. Make sure to switch to a fixed refresh rate
mode in display settings instead on such machines.Movie playback, movie writing and video capture works well with GStreamer 1.24.10,
but due to what seem to be shortcomings or bugs of current GStreamer releases,
video recording on Apple Silicon only works for video, not when also trying to
record audio - otherwise hangs will occur. On Intel Macs, video recording does
not work at all with GStreamer 1.24.10, but does for both video and audio with
GStreamer 1.22, however with the downside that playback of some movies fails.
So both GStreamer 1.22 and 1.24 have some limitations, pick the variant with
limitations you can better live with, until GStreamer is properly fixed in some
future GStreamer version.You should probably not yet use this release for real data collection if
highest reliability of visual stimulus presentation timing is required. Use
for less demanding scenarios may be fine, but tread carefully with this early
release!
All:
-
Screen: Fix PsychNormalizeTextureOrientation() for multi-window use.
Use of multiple onscreen windows could cause the wrong OpenGL context
of the wrong onscreen window to be in use during operation. Fix this.
Cfe. Unknown problem playing movies with Gstreamer on Ubuntu Linux - #8 by mantiuk -
Screen: Various improvements to movie playback. E.g., improve reliability of
playback with pixelFormat 6 and 8. -
Screen: Reduce chattiness of some status/debug output in general. Generally
refine status output a bit. -
AlphaRotateDemo.m: Small fixups for weirdly sized displays and formatting fixes.
Especially useful for the Retina displays of 16 inch Apple Silicon MacBookPro,
with uneven horizontal resolution. -
PsychPython/audio.py: Fix ‘AttributeError’ raised when creating a stream fails.
Contributed by GitHub user @mdcutone -
PsychColorimetric/LMSToMacBoyn(): “Add an example and save the correct version”,
some poorly documented fixes or improvements by the Brainard lab with mostly
void of information commit message. -
Various other smaller refinements, bug fixes and documentation updates.
Linux:
-
Psychtoolbox was built and tested against Matlab R2024b and Octave 5.2 and later.
-
PsychVulkan: Only use workaround against an AMDVLK bug that causes crash if the
used Vulkan display monitor has more than 64 video modes on AMDVLK driver versions
before v-2024.Q4.2, as the bug has been fixed in the upstream driver v-2024.Q4.2,
released early December 2024.
Windows:
-
Psychtoolbox was built and tested against Matlab R2024b and Octave 7.3.
-
Screen: Drop GStreamer DirectShow video capture. Prioritize Mediafoundation.
DirectShow video capture is unmaintained and strongly discouraged by GStreamer
folks since the year 2022, and indeed testing shows it is quite broken now.
WDM-KS kernel streaming is also deprecated since the year 2022. MediaFoundation
capture is the only recommended way forward. Limited testing on Windows 10 22H2
also shows it to be the most capable and stable right now (tested GStreamer 1.22).Drop support for DirectShow dshowvideosrc completely, and prefer Mediafoundation
mfvideosrc over the deprecated Kernel Streaming ksvideosrc. -
PsychVulkan/Windows: Disable fullscreen exclusive mode on shoddy AMD Vulkan drivers
again. This still does not work reliably and often leads to black screens instead
of stimulus display.
macOS:
-
Psychtoolbox was built and tested against native Matlab R2024b and against native
Octave 9.2 from HomeBrew, on macOS 13.7.1 Ventura for Intel Macs, and on macOS 14.5
Sonoma for Apple Silicon Macs. -
Initial support for running Psychtoolbox on macOS for Apple Silicon Macs with ARM
native Matlab and Octave. -
Bump minimum required macOS version to macOS 10.13 “High Sierra”. Effective this
means macOS 10.13 for IntelMacs, and macOS 11 “Big Sur” for Apple Silicon Macs
are required to run Psychtoolbox 3.0.20.Of course this new minimum is a bit redundant, because all macOS versions older
than macOS 13 are completely unsupported by Apple since October 2024, so running
anything older is at least a high computer security risk, and has lots of unfixed
remaining bugs and is therefore not a good idea. Additionally macOS 13 is needed
at a minimum on Apple Silicon Macs to allow proper operation of visual stimulators
from VPixx and Cambridge Research Systems. -
Fix video recording on macOS. Works fully with video + audio on macOS for Intel
Macs with GStreamer 1.22. Works with video only, no audio, on macOS for Apple
Silicon Macs. -
Implement initial pixelFormat 11 movie playback support on macOS for playback of
Deep color, Wide color gamut (WCG), and High Dynamic Range (HDR) movies. This
provides 10 bpc deep color, WCG and HDR, but at a lower performance than on other
operating systems, as Apples prehistoric OpenGL 2.1 implementation forces us to
use a less efficient decoding shader, and hardware accelerated video decoding can
not be used as of GStreamer 1.24.10, as it would reduce color precision to only 8
bpc which is utterly insufficient for WCG and HDR playback, causing significant
banding and HDR artefacts. -
Make pixelFormat 6 playback work without crashing.
-
Screen: Make Intel iGPU pageflip checking on recent macOS for Intel graphics chips
more robust. This may improve robustness of correctness checks on Intel integrated
graphics on Intel Macs with PsychtoolboxKernelDriver installed. Problem seen and
fixed on Intel Kabylake Gen 9.5 graphics of MacBookPro 2017. -
Fix some crashes on Octave for macOS when using Psychtoolbox after issuing a
“clear all”, or “clear mex”, or “clear Screen”, or “clear PsychVulkanCore” command.
Enjoy!
and thanks for all the hard work!!!