Python Image Stimulus¶
An image stimulus whose content is generated dynamically by Python code.
For information on the modules and functions available to your Python code, see Run Python File.
Note: To preserve the image’s aspect ratio on screen, x_size and y_size must be equal. When drawn, the larger dimension spans the full specified size, while the smaller dimension is scaled to maintain the aspect ratio.
Pixel buffer format
Pixel buffer width
Pixel buffer height
Pixel buffer expression
Name of a variable in which to store the elapsed time (in microseconds)
since the stimulus started playing (either implicitly due to autoplay
YES or via an explicit Play Dynamic Stimulus action).
YES, the stimulus will start playing automatically (as if by an implicit Play Dynamic Stimulus action) after it has been queued and Update Stimulus Display has been invoked. It will also stop playing automatically (as if by an implicit Stop Dynamic Stimulus action) after it has been dequeued and Update Stimulus Display is invoked.
By default, the alpha multiplier controls the transparency of the
1.0 is fully opaque, while
0.0 is fully tranparent.
Note: If the image contains an alpha channel, the embedded alpha value for each pixel is multiplied by the value of this parameter.
Source blending factor.
The parameters source_blend_factor, dest_blend_factor, source_alpha_blend_factor, and dest_alpha_blend_factor provide detailed control over how the color components and alpha multiplier of each fragment of the stimulus (the “source”) are combined with the color and alpha values already present in the framebuffer (the “destination”), which in turn result from blending the stimulus display background with any stimuli drawn beneath the source stimulus. These parameters correspond directly to the four arguments of the OpenGL function glBlendFuncSeparate. Please refer to that function’s reference page for explanations of the different blend factor options.
Note: Irrespective of the blend factors used, the blend equation
Destination blending factor. Accepts the same values as source_blend_factor.
Source alpha blending factor. Accepts the same values as source_blend_factor.
If omitted, the value of source_blend_factor is used.
Destination alpha blending factor. Accepts the same values as source_blend_factor.
If omitted, the value of dest_blend_factor is used.
Horizontal size (degrees).
Vertical size (degrees).
Horizontal center position (degrees)
Vertical center position (degrees)