>Psychtoolbox>PsychDemos

SimpleHDRDemo([imfilename]) - Load and show a high dynamic range (HDR) image
on a compatible HDR display setup.

Press any key to terminate the demo.

‘imfilename’ - Optional filename of the HDR image to load. This will load
a standard HDR demo image bundled with Matlab, if omitted, or abort if
the default demo image is missing. Currently only ‘.hdr’ RGBE images are
supported.

See “help PsychHDR” for system requirements and setup instructions for HDR
display. Once these are satisfied, converting a standard Psychtoolbox visual
stimulation script into a HDR script is straightforward, as shown in this simple
demo. Modify your scripts in the following manner:

1. Use (as most minimal setup) the sequence …

   PsychImaging(‘PrepareConfiguration’);
   PsychImaging(‘AddTask’, ‘General’, ‘EnableHDR’);
   win = PsychImaging(‘OpenWindow’, screenid);

   … instead of …

   win = Screen(‘OpenWindow’, screenid);

   … to open a fullscreen onscreen window on a HDR capable display device,
   which is attached to a HDR capable graphics card.

2. Use HDRRead(imfilename) instead of imread(imfilename) to load HDR
   image files as double() precision matrices.

3. Optional: Set the optional ‘floatprecision’ flag of Screen(‘MakeTexture’, …)
   to 1 or 2 to enforce creation of floating point precision HDR textures
   of a specific precision from your image matrix.

   By default, ‘floatprecision’ will be selected as 2 for single
   precision float fp32 format, which is the maximum precision for
   processing and displaying HDR images.

See the section ‘EnableHDR’ of “help PsychImaging” for more optional parameters
to pass to PsychImaging(‘AddTask’, ‘General’, ‘EnableHDR’); for customizing the
HDR display mode. See “help PsychHDR” for more helper subfunctions to customize
HDR display further at runtime, once the fullscreen onscreen HDR display window
has been opened and initially set up by PsychImaging(‘AddTask’, ‘General’, ‘EnableHDR’).