vision Package

This package contains implementation of visual stimuli.

stimuli.visual_stimulus Module

This module contains API of visual stimuli.

class mozaik.stimuli.vision.visual_stimulus.VisualStimulus(**params)

Bases: mozaik.stimuli.BaseStimulus

Abstract base class for visual stimuli.

This class defines all parameters common to all visual stimuli.

This class implements all functions specified by the mozaik.stimuli.stimulus.BaseStimulus interface. The only function that remains to be implemented by the user whenever creating a new stimulus by subclassing this class is the mozaik.stimuli.stimulus.BaseStimulus.frames() function.

This class also implements functions common to all visual stimuli that are required for it to be compatible with the mozaik.space.VisualSpace and class.

Mozaik parameters:  

background_luminance : SNumber(bounds=None, constant=False, default=None, inclusive_bounds=(True, True), period=None, readonly=False, units=1 lx (lux))

Background luminance. Maximum luminance of object allowed is 2*background_luminance

density : SNumber(bounds=None, constant=False, default=None, inclusive_bounds=(True, True), period=None, readonly=False, units=1.0 1/deg)

The density of stimulus - units per degree

location_x : SNumber(bounds=None, constant=False, default=None, inclusive_bounds=(True, True), period=None, readonly=False, units=1 deg (arcdegree))

x location of the center of visual region.

location_y : SNumber(bounds=None, constant=False, default=None, inclusive_bounds=(True, True), period=None, readonly=False, units=1 deg (arcdegree))

y location of the center of visual region.

size_x : SNumber(bounds=None, constant=False, default=None, inclusive_bounds=(True, True), period=None, readonly=False, units=1 deg (arcdegree))

The size of the region in degrees (asimuth).

size_y : SNumber(bounds=None, constant=False, default=None, inclusive_bounds=(True, True), period=None, readonly=False, units=1 deg (arcdegree))

The size of the region in degrees (elevation).

update()

Sets the current frame to the next frame in the sequence.

reset()

Reset to the first frame in the sequence.

next_frame()

For creating movies with NeuroTools.visualization.

stimuli.topographica_based Module

The file contains stimuli that use topographica to generate the stimulus

class mozaik.stimuli.vision.topographica_based.TopographicaBasedVisualStimulus(**params)

Bases: mozaik.stimuli.vision.visual_stimulus.VisualStimulus

As we do not handle transparency in the Topographica stimuli (i.e. all pixels of all stimuli difned here will have 0% transparancy) in this abstract class we disable the transparent flag defined by the mozaik.stimuli.visual_stimulus.VisualStimulus, to improve efficiency.

class mozaik.stimuli.vision.topographica_based.FullfieldDriftingSinusoidalGrating(**params)

Bases: mozaik.stimuli.vision.topographica_based.TopographicaBasedVisualStimulus

A full field sinusoidal grating stimulus.

Notes

max_luminance is interpreted as scale and size_x/2 as the bounding box radius.

Mozaik parameters:  

orientation : SNumber(bounds=[0, 3.141592653589793], constant=False, default=None, inclusive_bounds=(True, True), period=3.14159265359, readonly=False, units=1 rad (radian))

Grating orientation

temporal_frequency : SNumber(bounds=None, constant=False, default=None, inclusive_bounds=(True, True), period=None, readonly=False, units=1 Hz (hertz))

Temporal frequency of grating

spatial_frequency : SNumber(bounds=None, constant=False, default=None, inclusive_bounds=(True, True), period=None, readonly=False, units=1 cycles_per_degree)

Spatial frequency of grating

contrast : SNumber(bounds=[0, 100.0], constant=False, default=None, inclusive_bounds=(True, True), period=None, readonly=False, units=1 dimensionless)

Contrast of the stimulus

class mozaik.stimuli.vision.topographica_based.Null(**params)

Bases: mozaik.stimuli.vision.topographica_based.TopographicaBasedVisualStimulus

Blank stimulus.

class mozaik.stimuli.vision.topographica_based.NaturalImageWithEyeMovement(**params)

Bases: mozaik.stimuli.vision.topographica_based.TopographicaBasedVisualStimulus

A visual stimulus that simulates an eye movement over a static image.

Mozaik parameters:  

image_location : SString(constant=False, default=None, period=None, readonly=False, units=None)

Location of the image

size : SNumber(bounds=None, constant=False, default=None, inclusive_bounds=(True, True), period=None, readonly=False, units=1 deg (arcdegree))

The length of the longer axis of the image in visual degrees

eye_path_location : SString(constant=False, default=None, period=None, readonly=False, units=None)

Location of file containing the eye path (two columns of numbers)

eye_movement_period : SNumber(bounds=None, constant=False, default=None, inclusive_bounds=(True, True), period=None, readonly=False, units=1 ms (millisecond))

The time between two consequitve eye movements recorded in the eye_path file

class mozaik.stimuli.vision.topographica_based.DriftingGratingWithEyeMovement(**params)

Bases: mozaik.stimuli.vision.topographica_based.TopographicaBasedVisualStimulus

A visual stimulus that simulates an eye movement over a drifting gratings.

Mozaik parameters:  

orientation : SNumber(bounds=[0, 3.141592653589793], constant=False, default=None, inclusive_bounds=(True, True), period=3.14159265359, readonly=False, units=1 rad (radian))

Grating orientation

temporal_frequency : SNumber(bounds=None, constant=False, default=None, inclusive_bounds=(True, True), period=None, readonly=False, units=1 Hz (hertz))

Temporal frequency of grating

spatial_frequency : SNumber(bounds=None, constant=False, default=None, inclusive_bounds=(True, True), period=None, readonly=False, units=1 cycles_per_degree)

Spatial frequency of grating

eye_path_location : SString(constant=False, default=None, period=None, readonly=False, units=None)

Location of file containing the eye path (two columns of numbers)

eye_movement_period : SNumber(bounds=None, constant=False, default=None, inclusive_bounds=(True, True), period=None, readonly=False, units=1 ms (millisecond))

The time between two consequitve eye movements recorded in the eye_path file

contrast : SNumber(bounds=[0, 100.0], constant=False, default=None, inclusive_bounds=(True, True), period=None, readonly=False, units=1 dimensionless)

Contrast of the stimulus

class mozaik.stimuli.vision.topographica_based.DriftingSinusoidalGratingDisk(**params)

Bases: mozaik.stimuli.vision.topographica_based.TopographicaBasedVisualStimulus

A drifting sinusoidal grating confined to a apareture of specified radius.

Notes

size_x/2 is interpreted as the bounding box radius.

Mozaik parameters:  

orientation : SNumber(bounds=[0, 3.141592653589793], constant=False, default=None, inclusive_bounds=(True, True), period=3.14159265359, readonly=False, units=1 rad (radian))

Grating orientation

temporal_frequency : SNumber(bounds=None, constant=False, default=None, inclusive_bounds=(True, True), period=None, readonly=False, units=1 Hz (hertz))

Temporal frequency of the grating

radius : SNumber(bounds=None, constant=False, default=None, inclusive_bounds=(True, True), period=None, readonly=False, units=1 deg (arcdegree))

The radius of the grating disk - in degrees of visual field

spatial_frequency : SNumber(bounds=None, constant=False, default=None, inclusive_bounds=(True, True), period=None, readonly=False, units=1 cycles_per_degree)

Spatial frequency of the grating

contrast : SNumber(bounds=[0, 100.0], constant=False, default=None, inclusive_bounds=(True, True), period=None, readonly=False, units=1 dimensionless)

Contrast of the stimulus

class mozaik.stimuli.vision.topographica_based.DriftingSinusoidalGratingCenterSurroundStimulus(**params)

Bases: mozaik.stimuli.vision.topographica_based.TopographicaBasedVisualStimulus

A standard stimulus to probe orientation specific surround modulation: A drifting grating in center surrounded by a drifting grating in the surround. Orientations of both center and surround gratings can be varied independently.

Notes

max_luminance is interpreted as scale and size_x/2 as the bounding box radius.

Mozaik parameters:  

surround_orientation : SNumber(bounds=[0, 3.141592653589793], constant=False, default=None, inclusive_bounds=(True, True), period=3.14159265359, readonly=False, units=1 rad (radian))

Surround grating orientation

gap : SNumber(bounds=None, constant=False, default=None, inclusive_bounds=(True, True), period=None, readonly=False, units=1 deg (arcdegree))

The gap between center and surround grating - in degrees of visual field

temporal_frequency : SNumber(bounds=None, constant=False, default=None, inclusive_bounds=(True, True), period=None, readonly=False, units=1 Hz (hertz))

Temporal frequency of the grating (same for center and surround)

center_orientation : SNumber(bounds=[0, 3.141592653589793], constant=False, default=None, inclusive_bounds=(True, True), period=3.14159265359, readonly=False, units=1 rad (radian))

Center grating orientation

spatial_frequency : SNumber(bounds=None, constant=False, default=None, inclusive_bounds=(True, True), period=None, readonly=False, units=1 cycles_per_degree)

Spatial frequency of the grating (same for center and surround)

center_radius : SNumber(bounds=None, constant=False, default=None, inclusive_bounds=(True, True), period=None, readonly=False, units=1 deg (arcdegree))

The (outside) radius of the center grating disk - in degrees of visual field

surround_radius : SNumber(bounds=None, constant=False, default=None, inclusive_bounds=(True, True), period=None, readonly=False, units=1 deg (arcdegree))

The (outside) radius of the surround grating disk - in degrees of visual field

contrast : SNumber(bounds=[0, 100.0], constant=False, default=None, inclusive_bounds=(True, True), period=None, readonly=False, units=1 dimensionless)

Contrast of the stimulus