AiVision#

Initializing the AiVision Class#

An AI Vision Sensor is created by using the following constructor:

AiVision(port, colors, codes)

This constructor uses three parameter:

Parameter	Description
`port`	A valid Smart Port that the AI Vision Sensor is connected to.
`colors`	Optional. The name of one or more Colordesc objects.
`codes`	Optional. The name of one or more Codedesc objects.

# Create a new Color Signature "red" with the Colordesc class.
red = Colordesc(1, 207, 19, 25, 10.00, 0.20)
# Create a new AI Vision Sensor "ai_vision" with the AiVision
# class, with the "red' Colordesc.
ai_vision = AiVision(Ports.PORT1, red)

This ai_vision AiVision object and red Colordesc object will be used in all subsequent examples throughout this API documentation when referring to AiVision class methods.

Related Classes

Class Methods#

take_snapshot()#

The take_snapshot(type, count) method takes the current snapshot visible to the AI Vision Sensor and detects the objects of a given signature, code, or signature id.

Parameters	Description
type	A Colordesc, Codedesc, Tagdesc, or AiObjdesc object.
count	Optional. The maximum number of objects to obtain. The default is 8.

Returns: A tuple of of detected objects or an empty tuple if nothing is available.

while True:
    # Create a tuple named "red_objects" of detected objects
    # matching the "red" Colordesc.
    red_objects = ai_vision.take_snapshot(red)
    
    # Clear the screen/reset so that we can display 
    # new information.
    brain.screen.clear_screen()
    brain.screen.set_cursor(1, 1)
    
    # Print the amount of objects detected that matched
    # the "red" Colordesc using the len command.
    brain.screen.print("Object Count:", len(red_objects))
    # Wait 0.5 seconds before repeating the loop and
    # taking a new snapshot.
    wait(0.5, SECONDS)

largest_object()#

The largest_object() method retrieves the largest object detected by the AI Vision Sensor in the latest snapshot.

The object returned by largest_object() has fifteen properties that can be accessed to obtain various information about the detected object.

AI Vision Object Properties	Description
`id`	The object’s ID.
`type`	The object’s type.
`originX`	The top left x position of the object.
`originY`	The top left y position of the object.
`centerX`	The center x position of the object.
`centerY`	The center y position of the object.
`width`	The object’s width in pixels.
`height`	The object’s height in pixels.
`angle`	The object’s angle in pixels. Note: This is only usable with Color Codes/`Codedesc` objects.
`exists`	If the AI Vision camera detects the object. `True` if an object is detected, `False` if an object is not detected.
`tag`	The coordinates of an AprilTag.
`className`	The class name of the object.
`color`	The object’s color.
`score`	The confidence score for this object ranges from 0% - 100%. It represents how confident the AI Vision Sensor is in accurately identifying the object.
`area`	The area of the object`s bounding box in pixels.

Returns: An object or None if it does not exist.

while True: 
    # Create a tuple named "red_objects" of detected objects
    # matching the "red" Colordesc.
    red_objects = ai_vision.take_snapshot(red)
    
    # Clear the screen/reset so that we can display 
    # new information.
    brain.screen.clear_screen()
    brain.screen.set_cursor(1, 1)

    # Print the largest detected object's CenterX
    # coordinate to the Brain's screen.
    brain.screen.print("Center X: ", ai_vision.largest_object.centerX)
    # Wait 0.5 seconds before repeating the loop and
    # taking a new snapshot.
    wait(0.5, SECONDS)

object_count()#

The object_count() method returns the amount of detected objects in the last use of the take_snapshot method.

Returns: An integer as the amount of detected objects in the last use of the take_snapshot method.

tag_detection()#

The tag_detection(enable) method enables or disables AprilTag detection.

Parameters	Description
enable	`True` to enable AprilTag detection. `False` to disable it.

Returns: None.

color_detection()#

The color_detection(enable, merge) method enables or disables color and code object detection.

Parameters	Description
enable	`True` to enable color and color code detection. `False` to disable it.
merge	Optional. A boolean value which enables or disables the merging of adjacent color detections.

Returns: None.

model_detection(enable)#

The model_detection(enable) method enables or disables AI model object detection.

Parameters	Description
enable	`True` to enable AI model object detection. `False` to disable it.

Returns: None.

start_awb()#

The start_awb() method runs auto white balance.

Returns: None.

set()#

The set() method sets a new Color Signature or Color Code.

Returns: None.

installed()#

The installed() method checks for device connection.

Returns: True if the AI Vision Sensor is connected. False if it is not.

timestamp()#

The timestamp() method requests the timestamp of the last received status packet from the AI Vision Sensor.

Returns: Timestamp of the last received status packet in milliseconds.