added sbc_with_dots and dotted_sbc

stimuli/illusions/sbc.py

@@ -1,4 +1,6 @@
-from stimuli.components import rectangle
+import numpy as np
+from stimuli.utils import pixels_to_degrees, pad_img
+from stimuli.components import rectangle, disc
 
 
 def simultaneous_contrast(
@@ -36,10 +38,136 @@ def simultaneous_contrast(
     return {"img": img, "mask": mask}
 
 
+def sbc_with_dots(
+        ppd=10,
+        n_dots=(8, 9),
+        dot_radius=3.,
+        distance=1.,
+        target_shape=(4, 3),
+        vback=0.,
+        vdots=1.,
+        vtarget=0.5,
+        ):
+    """
+    Simultaneous contrast stimulus with dots
+
+    Parameters
+    ----------
+    ppd : int
+        pixels per degree (visual angle)
+    n_dots : (int, int)
+        stimulus size defined as the number of dots in y and x-directions
+    dot_radius : float
+        radius of dots
+    distance : float
+        distance between dots in degree visual angle
+    target_shape : (int, int)
+        target shape defined as the number of dots that fit into the target
+    vback : float
+        value for background
+    vdots : float
+        value for dots
+    vtarget : float
+        value for target
+
+    Returns
+    -------
+    A stimulus dictionary with the stimulus ['img'] and target mask ['mask']
+    """
+
+    padding = (distance/2., distance/2., distance/2., distance/2.)
+    patch = disc(ppd, dot_radius, vback=0., vdisc=vdots)
+    patch = pad_img(patch, padding, ppd, 0.)
+
+    img_height = pixels_to_degrees(n_dots[0] * patch.shape[0], ppd)
+    img_width = pixels_to_degrees(n_dots[1] * patch.shape[1], ppd)
+    rec_height = pixels_to_degrees(target_shape[0] * patch.shape[0], ppd)
+    rec_width = pixels_to_degrees(target_shape[1] * patch.shape[1], ppd)
+
+    # Create the sbc in the background:
+    tposy = (img_height-rec_height) / 2.
+    tposx = (img_width-rec_width) / 2.
+    img = rectangle(ppd, im_size=(img_height, img_width), rect_size=(rec_height, rec_width),
+                    rect_pos=(tposy, tposx), vback=vback, vrect=vtarget)
+
+    patch = np.tile(patch, (n_dots[0], n_dots[1]))
+    indices_dots = np.where((patch != 0))
+    img[indices_dots] = vdots
+    mask = None
+    return {"img": img, "mask": mask}
+
+
+def dotted_sbc(
+        ppd=10,
+        n_dots=(8, 9),
+        dot_radius=3.,
+        distance=1.,
+        target_shape=(4, 3),
+        vback=0.,
+        vdots=1.,
+        vtarget=0.5,
+        ):
+    """
+    Simultaneous contrast stimulus with dots
+
+    Parameters
+    ----------
+    ppd : int
+        pixels per degree (visual angle)
+    n_dots : (int, int)
+        stimulus size defined as the number of dots in y and x-directions
+    dot_radius : float
+        radius of dots
+    distance : float
+        distance between dots in degree visual angle
+    target_shape : (int, int)
+        target shape defined as the number of dots that fit into the target
+    vback : float
+        value for background
+    vdots : float
+        value for dots
+    vtarget : float
+        value for target
+
+    Returns
+    -------
+    A stimulus dictionary with the stimulus ['img'] and target mask ['mask']
+    """
+
+    padding = (distance/2., distance/2., distance/2., distance/2.)
+    patch = disc(ppd, dot_radius, vback=0., vdisc=vdots)
+    patch = pad_img(patch, padding, ppd, 0.)
+
+    img_height = pixels_to_degrees(n_dots[0] * patch.shape[0], ppd)
+    img_width = pixels_to_degrees(n_dots[1] * patch.shape[1], ppd)
+    rec_height = pixels_to_degrees(target_shape[0] * patch.shape[0], ppd)
+    rec_width = pixels_to_degrees(target_shape[1] * patch.shape[1], ppd)
+
+    # Create the sbc and img:
+    tposy = (img_height-rec_height) / 2.
+    tposx = (img_width-rec_width) / 2.
+    sbc = rectangle(ppd, im_size=(img_height, img_width), rect_size=(rec_height, rec_width),
+                    rect_pos=(tposy, tposx), vback=vback, vrect=vtarget)
+    img = np.ones(sbc.shape) * vback
+
+    patch = np.tile(patch, (n_dots[0], n_dots[1]))
+    indices_dots_back = np.where((patch != 0) & (sbc == vback))
+    indices_dots_target = np.where((patch != 0) & (sbc == vtarget))
+    img[indices_dots_back] = vdots
+    img[indices_dots_target] = vtarget
+    mask = None
+    return {"img": img, "mask": mask}
+
+
 if __name__ == "__main__":
     import matplotlib.pyplot as plt
-    from stimuli.utils import plot_stim
+    from stimuli.utils import plot_stimuli
+
+    stims = {
+        "SBC": simultaneous_contrast(),
+        "SBC with dots": sbc_with_dots(),
+        "Dotted SBC": dotted_sbc(),
+    }
 
-    stim = simultaneous_contrast()
-    plot_stim(stim, stim_name="Simultaneous brightness contrast")
+    plot_stimuli(stims)
     plt.show()