class visbrain.objects.ColorbarObj(name, rect=(-0.7, -2, 1.5, 4), transform=None, parent=None, verbose=None, **kwargs)[source][source]

Create a colorbar object.


Name of the colorbar object. Alternatively, you can pass an other object (like BrainObj or SourceObj) to get their colorbar.

recttuple | (-.7, -2, 1.5, 4)

Camera rectangle. The rect input must be a tuple of four floats describing where the camera (start_x, start_y, length_x, length_y).

cmapstring | None

Matplotlib colormap (like ‘viridis’, ‘inferno’…).

climtuple/list | None

Colorbar limit. Every values under / over clim will clip.

isvminbool | False

Activate/deactivate vmin.

vminfloat | None

Every values under vmin will have the color defined using the under parameter.

vmaxfloat | None

Every values over vmin will have the color defined using the over parameter.

undertuple/string | None

Matplotlib color under vmin.

overtuple/string | None

Matplotlib color over vmax.

cblabelstring | ‘’

Colorbar label.

cbtxtszfloat | 5..

Text size of the colorbar label.

cbtxtshfloat | 2.3

Shift for the colorbar label.

txtcolorstring | ‘white’

Text color.

txtszfloat | 3.

Text size for clim/vmin/vmax text.

txtshfloat | 1.2

Shift for clim/vmin/vmax text.

borderbool | True

Display colorbar borders.

bwfloat | 2.

Border width.

limtxtbool | True

Display vmin/vmax text.

bgcolortuple/string | (0., 0., 0.)

Background color of the colorbar canvas.

ndigitsint | 2

Number of digits for the text.

widthfloat | 0.17

Colorbar width.

transformVisPy.visuals.transforms | None

VisPy transformation to set to the parent node.

parentVisPy.parent | None

Markers object parent.


Verbosity level.


List of supported shortcuts :

  • s : save the figure

  • <delete> : reset camera


>>> from visbrain.objects import ColorbarObj
>>> cb = ColorbarObj('cbar', cmap='viridis', clim=(4., 78.2), vmin=10.,
>>>                  vmax=72., cblabel='Colorbar title', under='gray',
>>>                  over='red', txtcolor='black', cbtxtsz=40, cbtxtsh=2.,
>>>                  txtsz=20., width=.04)
>>> cb.preview()


__init__(self, name[, rect, transform, …])


animate(self[, step, interval, iterations])

Animate the object.


Get a copy of the object.


Tree description.

preview(self[, bgcolor, axis, xyz, show, …])

Previsualize the result.

record_animation(self, name[, n_pic, bgcolor])

Record an animated object and save as a *.gif file.


Render the canvas.

screenshot(self, saveas[, print_size, dpi, …])

Take a screeshot of the scene.

set_shortcuts_to_canvas(self, canvas)

Set shortcuts to a VisbrainCanvas.


Return a dictionary of all colorbar args.

to_kwargs(self[, addisminmax])

Return a dictionary for input arguments.


Fonction to run when an update is needed.

update_from_dict(self, kwargs)

Update attributes from a dictionary.

animate(self, step=1.0, interval='auto', iterations=-1)[source]

Animate the object.

Note that this method can only be used with 3D objects.

stepfloat | 1.

Rotation step.

intervalfloat | ‘auto’

Time between events in seconds. The default is ‘auto’, which attempts to find the interval that matches the refresh rate of the current monitor. Currently this is simply 1/60.

iterationsint | -1

Number of iterations. Can be -1 for infinite.

property cmap

Get the cmap value.


Get a copy of the object.

property data_folder

Get the data_folder value.

property name

Get the name value.

property parent

Get the parent value.

preview(self, bgcolor='black', axis=False, xyz=False, show=True, obj=None, size=(1200, 800), mpl=False, **kwargs)[source]

Previsualize the result.

bgcolorarray_like/string/tuple | ‘black’

Background color for the preview.

axisbool | False

Add x and y axis with ticks.

xyzbool | False

Add an (x, y, z) axis to the scene.

objVisbrainObj | None

Pass a Visbrain object if you want to use the camera of an other object.

sizetuple | (1200, 800)

Default size of the window.

mplbool | False

Use Matplotlib to display the object. This result in a non interactive figure.

kwargsdict | {}

Optional arguments are passed to the VisbrainCanvas class.

record_animation(self, name, n_pic=10, bgcolor=None)[source]

Record an animated object and save as a *.gif file.

Note that this method :

  • Can only be used with 3D objects.

  • Requires the python package imageio


Name of the gif file (e.g ‘myfile.gif’)

n_picint | 10

Number of pictures to use to render the gif.

bgcolorstring, tuple, list | None

Background color.


Render the canvas.


Array of shape (n_rows, n_columns, 4) where 4 describes the RGBA components.

screenshot(self, saveas, print_size=None, dpi=300.0, unit='centimeter', factor=None, region=None, autocrop=False, bgcolor=None, transparent=False, obj=None, line_width=1.0, **kwargs)[source]

Take a screeshot of the scene.

By default, the rendered canvas will have the size of your screen. The screenshot() method provides two ways to increase to exported image resolution :

  • Using print_size, unit and dpi inputs : specify the size of the image at a specific dpi level. For example, you might want to have an (10cm, 15cm) image at 300 dpi.

  • Using the factor input : multiply the default image size by this factor. For example, if you have a (1920, 1080) monitor and if factor is 2, the exported image should have a shape of (3840, 2160) pixels.


The name of the file to be saved. This file must contains a extension like .png, .tiff, .jpg…

print_sizetuple | None

The desired print size. This argument should be used in association with the dpi and unit inputs. print_size describe should be a tuple of two floats describing (width, height) of the exported image for a specific dpi level. The final image might not have the exact desired size but will try instead to find a compromize regarding to the proportion of width/height of the original image.

dpifloat | 300.

Dots per inch for printing the image.

unit{‘centimeter’, ‘millimeter’, ‘pixel’, ‘inch’}

Unit of the printed size.

factorfloat | None

If you don’t want to use the print_size input, factor simply multiply the resolution of your screen.

regiontuple | None

Select a specific region. Must be a tuple of four integers each one describing (x_start, y_start, width, height).

autocropbool | False

Automaticaly crop the figure in order to have the smallest space between the brain and the border of the picture.

bgcolorarray_like/string | None

The background color of the image.

transparentbool | False

Specify if the exported figure have to contains a transparent background.

objVisbrainObj | None

Pass a Visbrain object if you want to use the camera of an other object for the sceen rendering.

kwargsdict | {}

Optional arguments are passed to the VisbrainCanvas class.

property transform

Get the transform value.

property visible_obj

Get the visible_obj value.