fiftyone.core.stages.SelectGroupSlices

class documentation

class SelectGroupSlices(ViewStage): (source)

Constructor: SelectGroupSlices(slices, media_type, flat, _allow_mixed, _force_mixed)

Selects the specified group slice(s) from a grouped collection.

When flat==True, the returned view is a flattened non-grouped view containing the samples from the slice(s) of interest.

When flat=False, the returned view is a grouped collection containing only the slice(s) of interest.

Note

When flat=True, this stage performs a $lookup that pulls the requested slice(s) for each sample in the input collection from the source dataset. As a result, the stage emits unfiltered samples.

Examples:

import fiftyone as fo

dataset = fo.Dataset()
dataset.add_group_field("group", default="ego")

group1 = fo.Group()
group2 = fo.Group()

dataset.add_samples(
    [
        fo.Sample(
            filepath="/path/to/left-image1.jpg",
            group=group1.element("left"),
        ),
        fo.Sample(
            filepath="/path/to/video1.mp4",
            group=group1.element("ego"),
        ),
        fo.Sample(
            filepath="/path/to/right-image1.jpg",
            group=group1.element("right"),
        ),
        fo.Sample(
            filepath="/path/to/left-image2.jpg",
            group=group2.element("left"),
        ),
        fo.Sample(
            filepath="/path/to/video2.mp4",
            group=group2.element("ego"),
        ),
        fo.Sample(
            filepath="/path/to/right-image2.jpg",
            group=group2.element("right"),
        ),
    ]
)

#
# Retrieve the samples from the "ego" group slice
#

stage = fo.SelectGroupSlices("ego")
view = dataset.add_stage(stage)

#
# Retrieve the samples from the "left" or "right" group slices
#

stage = fo.SelectGroupSlices(["left", "right"])
view = dataset.add_stage(stage)

#
# Select only the "left" and "right" group slices
#

stage = fo.SelectGroupSlices(["left", "right"], flat=False)
view = dataset.add_stage(stage)

#
# Retrieve all image samples
#

stage = fo.SelectGroupSlices(media_type="image")
view = dataset.add_stage(stage)

Parameters
slices	a group slice or iterable of group slices to select. If neither argument is provided, a flattened list of all samples is returned
media_type	a media type or iterable of media types whose slice(s) to select
flat	whether to return a flattened collection (True) or a grouped collection (False)

Method	`__init__`	Undocumented
Method	`get_group_media_types`	Returns the group media types outputted by this stage, if any, when applied to the given collection, if and only if they are different from the input collection.
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	`to_mongo`	Returns the MongoDB aggregation pipeline for the stage.
Method	`validate`	Validates that the stage can be applied to the given collection.
Property	`flat`	Whether to generate a flattened collection.
Property	`flattens_groups`	Whether this stage flattens groups into a non-grouped collection.
Property	`media_type`	The media type(s) whose slices to select.
Property	`slices`	The group slice(s) to select.
Class Method	`_params`	Returns a list of JSON dicts describing the stage's supported parameters.
Method	`_get_slices`	Undocumented
Method	`_kwargs`	Returns a list of `[name, value]` lists describing the parameters of this stage instance.
Method	`_make_pipeline`	Undocumented
Method	`_make_root_pipeline`	Undocumented
Instance Variable	`_allow_mixed`	Undocumented
Instance Variable	`_flat`	Undocumented
Instance Variable	`_force_mixed`	Undocumented
Instance Variable	`_media_type`	Undocumented
Instance Variable	`_slices`	Undocumented

Inherited from ViewStage:

Method	`__eq__`	Undocumented
Method	`__repr__`	Undocumented
Method	`__str__`	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_excluded_fields`	Returns a list of fields that have been excluded 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	`get_group_expr`	Returns the dynamic group expression for the given stage, if any.
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	`_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.
Method	`_serialize`	Returns a JSON dict representation of the `ViewStage`.
Instance Variable	`_uuid`	Undocumented

def __init__(self, slices=None, media_type=None, flat=True, _allow_mixed=False, _force_mixed=False): (source) ¶

Undocumented

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

overrides fiftyone.core.stages.ViewStage.get_group_media_types

Returns the group media types outputted by this stage, if any, when applied to the given collection, if and only if they are different from the input collection.

Parameters
sample_collection	the `fiftyone.core.collections.SampleCollection` to which the stage is being applied
Returns
a dict mapping slice names to media types, or `None` if the stage does not change the types

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

overrides fiftyone.core.stages.ViewStage.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.

Parameters
sample_collection	the `fiftyone.core.collections.SampleCollection` to which the stage is being applied
Returns
the media type, or `None` if the stage does not change the type

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
flat = (source) ¶

Whether to generate a flattened collection.

@property
flattens_groups = (source) ¶

overrides fiftyone.core.stages.ViewStage.flattens_groups

Whether this stage flattens groups into a non-grouped collection.

The possible return values are:

True: this stage flattens groups
False: this stage does not flatten groups
None: this stage does not change group status

@property
media_type = (source) ¶

The media type(s) whose slices to select.

@property
slices = (source) ¶

The group slice(s) to select.

@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 _get_slices(self, sample_collection): (source) ¶

Undocumented

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 _make_pipeline(self, sample_collection): (source) ¶

Undocumented

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

Undocumented

_allow_mixed = (source) ¶

Undocumented

_flat = (source) ¶

Undocumented

_force_mixed = (source) ¶

Undocumented

_media_type = (source) ¶

Undocumented

_slices = (source) ¶

Undocumented