fiftyone.core.stages.LimitLabels

class documentation

class LimitLabels(ViewStage): (source)

Constructor: LimitLabels(field, limit)

Limits the number of fiftyone.core.labels.Label instances in the specified labels list field of each sample in a collection.

The specified field must be one of the following types:

Examples:

import fiftyone as fo
from fiftyone import ViewField as F

dataset = fo.Dataset()
dataset.add_samples(
    [
        fo.Sample(
            filepath="/path/to/image1.png",
            predictions=fo.Detections(
                detections=[
                    fo.Detection(
                        label="cat",
                        bounding_box=[0.1, 0.1, 0.5, 0.5],
                        confidence=0.9,
                    ),
                    fo.Detection(
                        label="dog",
                        bounding_box=[0.2, 0.2, 0.3, 0.3],
                        confidence=0.8,
                    ),
                ]
            ),
        ),
        fo.Sample(
            filepath="/path/to/image2.png",
            predictions=fo.Detections(
                detections=[
                    fo.Detection(
                        label="cat",
                        bounding_box=[0.5, 0.5, 0.4, 0.4],
                        confidence=0.95,
                    ),
                    fo.Detection(label="rabbit"),
                ]
            ),
        ),
        fo.Sample(
            filepath="/path/to/image4.png",
            predictions=None,
        ),
    ]
)

#
# Only include the first detection in the `predictions` field of each
# sample
#

stage = fo.LimitLabels("predictions", 1)
view = dataset.add_stage(stage)

Parameters
field	the labels list field to filter
limit	the maximum number of labels to include in each labels list. If a non-positive number is provided, all lists will be empty

Method	`__init__`	Undocumented
Method	`get_edited_fields`	Returns a list of names of fields or embedded fields that may have been edited by the stage, if any.
Method	`get_filtered_fields`	Returns a list of names of fields or embedded fields that contain arrays have been filtered by the stage, if any.
Method	`to_mongo`	Returns the MongoDB aggregation pipeline for the stage.
Method	`validate`	Validates that the stage can be applied to the given collection.
Property	`field`	The labels field to limit.
Property	`limit`	The maximum number of labels to allow in each labels list.
Class Method	`_params`	Returns a list of JSON dicts describing the stage's supported parameters.
Method	`_kwargs`	Returns a list of `[name, value]` lists describing the parameters of this stage instance.
Method	`_needs_frames`	Whether the stage requires frame labels of video samples to be attached.
Method	`_needs_group_slices`	Whether the stage requires group slice(s) to be attached.
Instance Variable	`_field`	Undocumented
Instance Variable	`_is_frame_field`	Undocumented
Instance Variable	`_labels_list_field`	Undocumented
Instance Variable	`_limit`	Undocumented

Inherited from ViewStage:

Method	`__eq__`	Undocumented
Method	`__repr__`	Undocumented
Method	`__str__`	Undocumented
Method	`get_excluded_fields`	Returns a list of fields that have been excluded by the stage, if any.
Method	`get_group_expr`	Returns the dynamic group expression for the given stage, if any.
Method	`get_media_type`	Returns the media type outputted by this stage when applied to the given collection, if and only if it is different from the input type.
Method	`get_selected_fields`	Returns a list of fields that have been selected by the stage, if any.
Method	`load_view`	Loads the `fiftyone.core.view.DatasetView` containing the output of the stage.
Property	`has_view`	Whether this stage's output view should be loaded via `load_view` rather than appending stages to an aggregation pipeline via `to_mongo`.
Property	`outputs_dynamic_groups`	Whether this stage outputs or flattens dynamic groups.
Class Method	`_from_dict`	Creates a `ViewStage` instance from a serialized JSON dict representation of it.
Method	`_serialize`	Returns a JSON dict representation of the `ViewStage`.
Instance Variable	`_uuid`	Undocumented

def __init__(self, field, limit): (source) ¶

Undocumented

def get_edited_fields(self, sample_collection, frames=False): (source) ¶

overrides fiftyone.core.stages.ViewStage.get_edited_fields

Returns a list of names of fields or embedded fields that may have been edited by the stage, if any.

The "frames." prefix should be omitted when frames is True.

Parameters
sample_collection	the `fiftyone.core.collections.SampleCollection` to which the stage is being applied
frames:`False`	whether to return sample-level (False) or frame-level (True) fields
Returns
a list of fields, or `None` if no fields have been edited

def get_filtered_fields(self, sample_collection, frames=False): (source) ¶

overrides fiftyone.core.stages.ViewStage.get_filtered_fields

Returns a list of names of fields or embedded fields that contain arrays have been filtered by the stage, if any.

For example, if a stage filters a fiftyone.core.labels.Detections field called "predictions", it should include "predictions.detections" in the returned list.

The "frames." prefix should be omitted when frames is True.

Parameters
sample_collection	the `fiftyone.core.collections.SampleCollection` to which the stage is being applied
frames:`False`	whether to return sample-level (False) or frame-level (True) fields
Returns
a list of fields, or `None` if no fields have been filtered

def to_mongo(self, sample_collection): (source) ¶

overrides fiftyone.core.stages.ViewStage.to_mongo

Returns the MongoDB aggregation pipeline for the stage.

Only usable if has_view is False.

Parameters
sample_collection	the `fiftyone.core.collections.SampleCollection` to which the stage is being applied
Returns
a MongoDB aggregation pipeline (list of dicts)

def validate(self, sample_collection): (source) ¶

overrides fiftyone.core.stages.ViewStage.validate

Validates that the stage can be applied to the given collection.

Parameters
sample_collection	a `fiftyone.core.collections.SampleCollection`
Raises
`ViewStageError`	if the stage cannot be applied to the collection

@property
field = (source) ¶

The labels field to limit.

@property
limit = (source) ¶

The maximum number of labels to allow in each labels list.

@classmethod
def _params(cls): (source) ¶

overrides fiftyone.core.stages.ViewStage._params

Returns a list of JSON dicts describing the stage's supported parameters.

Returns
a list of JSON dicts

def _kwargs(self): (source) ¶

overrides fiftyone.core.stages.ViewStage._kwargs

Returns a list of [name, value] lists describing the parameters of this stage instance.

Returns
a list of `[name, value]` lists

def _needs_frames(self, sample_collection): (source) ¶

overrides fiftyone.core.stages.ViewStage._needs_frames

Whether the stage requires frame labels of video samples to be attached.

Parameters
sample_collection	the `fiftyone.core.collections.SampleCollection` to which the stage is being applied
Returns
True/False

def _needs_group_slices(self, sample_collection): (source) ¶

overrides fiftyone.core.stages.ViewStage._needs_group_slices

Whether the stage requires group slice(s) to be attached.

Parameters
sample_collection	the `fiftyone.core.collections.SampleCollection` to which the stage is being applied
Returns
None, or a list of group slices

_field = (source) ¶

Undocumented

_is_frame_field = (source) ¶

Undocumented

_labels_list_field = (source) ¶

Undocumented

_limit = (source) ¶

Undocumented