BrightSideHDR(cmd [, arg1][, arg2]) – Psychtoolbox interface to
BrightSide Technologies High Dynamic Range display device.

This function is used to set up and interface with the High Dynamic Range
display of BrightSide Technologies. It is a Matlab wrapper around lower
level GLSL Psychtoolbox functions and the low-level BrightSideCore.dll
MEX-File. You need to have Brightsides DLL’s (and the display device)
installed on your machine for this to work. Without the DLL’s this will
simply crash. See “help BSRuntimeLibs” for information about

cmd - The command that BrightSideHDR should execute. cmd can be any of
the following:

Open a window on the HDR display as with Screen(‘OpenWindow’, …),
perform all HDR initialization:

[win, winRect] = BrightSideHDR(‘OpenWindow’, screenid, …);

This will execute Screen(‘OpenWindow’) with all proper parameters,
followed by BrightSide HDR init routines. It is a completely sufficient
drop in replacement for Screen(‘OpenWindow’), accepting and returning
exactly the same arguments that Screen() would do, adjusting all
parameters to the constraints of the BrightSideHDR, if necessary.

[win, winRect] = BrightSideHDR(‘DummyOpenWindow’, screenid, …);
Same as OpenWindow, but just init a dummy mode that operates on standard
displays without the Brightside-Libraries - useful for off-site testing.

[win, winRect] = BrightSideHDR(‘RawOpenWindow’, screenid, …);
Same as DummyOpenWindow, but just init a bare-minimum window on the HDR
display suitable for playback of previously computed raw framebuffer
images (see raw capture and replay support below). This will essentially
open a fullscreen window on the HDR display, with proper window settings
and identity gamma tables to make sure framebuffer content is passed
unaltered 1-to-1 to the display. The imaging pipeline is disabled, this
is a pure “fast replay” mode of content created in a previous session.

In most applications you won’t ever need to use any of the commands
below, as PTB does all this stuff automatically behind the scenes…
Ignore them unless you know what you’re doing.

BrightSideHDR(‘Initialize’, win [, dummy]); – Initialize the BrightSide libraries
for HDR output into onscreen window ‘win’. Onscreen window ‘win’ must have been
opened before on a screen which corresponds to the attached High Dynamic Range
display device. If you set ‘dummy’ to 1, then we are in emulation mode,
i.e., we work without invocation of the mex file and without a real HDR
display. This call will also attach all callback functions to the proper
hooks for the given onscreen window ‘win’ inside the Screen() command.

BrightSideHDR(‘Debuglevel’, level); – Set level of verbosity for
debugging. The default is zero which means to be silent. A level of 1
produces some debug output.


[sourceWin, destWin] = BrightSideHDR(‘CreateSnapshotBufferPair’);

  • Create a pair of offscreen windows useable for “offline” HDR->BrightSide
    conversion. Will create ‘sourceWin’ as a offscreen window with 32bpc
    float RGBA format, ‘destWin’ as a offscreenwindow with 8 bpc RGBA format.
    Both windows will have the size of the HDR displays framebuffer.

You can draw into the ‘sourceWin’ just as you’d do to an onscreen window.
Then you can call BrightSideHDR(‘ConvertImageToSnapshotBuffer’, destWin,
sourceWin); to convert the HDR image into a BrightSide formatted image in
‘destWin’. You can use ‘destWin’ or its content in the
BrightSideHDR(‘BlitRawFramebufferSnapshot’) call for quick “replay” of
HDR content.

[rawImg] = BrightSideHDR(‘ConvertImageToSnapshotBuffer’, destWin, sourceWin);

  • Convert HDR image in offscreen window ‘sourceWin’ into a HDR
    useable raw image in offscreen window ‘destWin’. Optionally return a
    Matlab uint8 RGB image matrix with the raw data as 1st return argument

You could save ‘rawImg’ to disk and later load it and “replay” it on the
HDR display via calls to BrightSideHDR(‘BlitRawFramebufferSnapshot’,

rawSnapshotMatrix = BrightSideHDR(‘GetRawFramebufferSnapshot’);
-Call immediately after Screen(‘Flip’). This will create a “screenshot” of the
framebuffer for the currently displaying HDR image and return a Matlab
matrix with proper raw framebuffer data, formatted for the HDR display.
Can be used to Screen(‘MakeTexture’) a texture that you can blit into the
framebuffer via BrightSideHDR(‘BlitRawFramebufferSnapshot’) without need
for expensive conversion at runtime.

BrightSideHDR(‘BlitRawFramebufferSnapshot’, sourceWin); Blit the given
RGB8 or RGBA8 texture or offscreen window into the framebuffer of HDR
display, so it gets displayed at the next invocation of Screen(‘Flip’).
The ‘sourceWin’ must be a texture or offscreen window whose image content
was previously created by one of the raw snapshotting functions above,
ie., it must be already encoded in the special data format for BrightSide

Callbacks: Usually called automatically by Screen(), no need to use them
in your script directly! Some of them may disappear in the future,
getting subsumed by Screen()’s internal imaging pipeline.

BrightSideHDR(‘BrightSideExecuteBlit’, win); – This will convert
the HDR image content in the HDR backbuffer into the special data
format needed by the HDR display hardware. This is called by PTB
automatically, don’t call it yourself!

BrightSideHDR(‘Shutdown’); – Shut down the HDR device and core library,
switch PTB back to standard LDR output. This is called by PTB
automatically, don’t call it yourself!

Path   Retrieve current version from GitHub | View changelog