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# fiftyone.utils.yolo

Utilities for working with datasets in YOLO format.

Copyright 2017-2026, Voxel51, Inc.
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[voxel51.com](https://voxel51.com/)
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**Functions:**

| [`add_yolo_labels`](#fiftyone.utils.yolo.add_yolo_labels)(sample_collection, ...[, ...])        | Adds the given YOLO-formatted labels to the collection.   |
|-------------------------------------------------------------------------------------------------|-----------------------------------------------------------|
| [`load_yolo_annotations`](#fiftyone.utils.yolo.load_yolo_annotations)(txt_path, classes[, ...]) | Loads the YOLO-style annotations from the given TXT file. |

**Classes:**

| [`YOLOv4DatasetImporter`](#fiftyone.utils.yolo.YOLOv4DatasetImporter)([dataset_dir, ...])       | Importer for YOLOv4 datasets stored on disk.            |
|-------------------------------------------------------------------------------------------------|---------------------------------------------------------|
| [`YOLOv5DatasetImporter`](#fiftyone.utils.yolo.YOLOv5DatasetImporter)([dataset_dir, ...])       | Importer for YOLOv5 datasets stored on disk.            |
| [`YOLOv4DatasetExporter`](#fiftyone.utils.yolo.YOLOv4DatasetExporter)([export_dir, ...])        | Exporter that writes YOLOv4 datasets to disk.           |
| [`YOLOv5DatasetExporter`](#fiftyone.utils.yolo.YOLOv5DatasetExporter)([export_dir, split, ...]) | Exporter that writes YOLOv5 datasets to disk.           |
| [`YOLOAnnotationWriter`](#fiftyone.utils.yolo.YOLOAnnotationWriter)()                           | Class for writing annotations in YOLO-style TXT format. |

### fiftyone.utils.yolo.add_yolo_labels(sample_collection, label_field, labels_path, classes, label_type='detections', mask_size=None, include_missing=False)

Adds the given YOLO-formatted labels to the collection.

Each YOLO txt file should be a space-delimited file whose rows define
objects in one of the following formats:

```default
# Detections
<target> <x-center> <y-center> <width> <height>
<target> <x-center> <y-center> <width> <height> <confidence>

# Instance segmentations or polygons
<target> <x1> <y1> <x2> <y2> <x3> <y3> ...
```

where `target` is the zero-based integer index of the object class label
from `classes` and the bounding box coordinates are expressed as relative
coordinates in `[0, 1] x [0, 1]`.

* **Parameters:**
  * **sample_collection** – a
    [`fiftyone.core.collections.SampleCollection`](fiftyone.core.collections.md#fiftyone.core.collections.SampleCollection)
  * **label_field** – the label field in which to store the labels. The field
    will be created if necessary
  * **labels_path** – 

    the YOLO-formatted labels to load. This can be any of the
    following:
    - a dict mapping either image filenames or absolute filepaths to
      YOLO TXT filepaths. The image filenames/filepaths should match
      those in `sample_collection`, in any order
    - a list of YOLO TXT filepaths corresponding 1-1 to the samples
      in `sample_collection`
    - a directory containing YOLO TXT files whose filenames (less
      extension) correspond to image filenames in
      `sample_collection`, in any order
  * **classes** – the list of class label strings
  * **label_type** ( *"detections"*) – the label format to load. The supported
    values are `("detections", "instances", "polylines")`
  * **mask_size** (*None*) – an optional `(width, height)` at which to render
    each instance mask. Only used when `label_type="instances"`. If
    no mask size is provided then instance masks are rendered
    proportionally to each image’s dimensions
  * **include_missing** (*False*) – whether to insert empty labels for any samples
    in the input collection whose `label_field` is `None` after
    import

### *class* fiftyone.utils.yolo.YOLOv4DatasetImporter(dataset_dir=None, data_path=None, labels_path=None, images_path=None, objects_path=None, classes=None, label_type='detections', mask_size=None, include_all_data=False, shuffle=False, seed=None, max_samples=None)

Bases: [`LabeledImageDatasetImporter`](fiftyone.utils.data.importers.md#fiftyone.utils.data.importers.LabeledImageDatasetImporter), [`ImportPathsMixin`](fiftyone.utils.data.importers.md#fiftyone.utils.data.importers.ImportPathsMixin)

Importer for YOLOv4 datasets stored on disk.

See [this page](../user_guide/import_datasets.md#yolov4dataset-import) for format details.

* **Parameters:**
  * **dataset_dir** (*None*) – the dataset directory. If omitted, `data_path`
    and/or `labels_path` must be provided
  * **data_path** (*None*) – 

    an optional parameter that enables explicit control
    over the location of the media. Can be any of the following:
    - a folder name like `"data"` or `"data/"` specifying a
      subfolder of `dataset_dir` where the media files reside
    - an absolute directory path where the media files reside. In
      this case, the `dataset_dir` has no effect on the location of
      the data

    If None, this parameter will default to whichever of `data/` or
    `data.json` exists in the dataset directory
  * **labels_path** (*None*) – 

    an optional parameter that enables explicit control
    over the location of the labels. Can be any of the following:
    - a folder name like `"labels"` or `"labels/"` specifying the
      location of the labels in `dataset_dir`
    - an absolute filepath to the labels. In this case,
      `dataset_dir` has no effect on the location of the labels

    If None, the labels are assumed to be in the same folder as the
    data
  * **images_path** (*None*) – 

    an optional parameter that enables explicit
    control over the location of the image listing file. Can be any of
    the following:
    - a filename like `"images.txt"` specifying the location of the
      image listing file labels in `dataset_dir`
    - an absolute filepath to the image listing file. In this case,
      `dataset_dir` has no effect on the location of the file

    If None, the parameter will default to `images.txt`
  * **objects_path** (*None*) – 

    an optional parameter that enables explicit
    control over the location of the object names file. Can be any of
    the following:
    - a filename like `"obj.names"` specifying the location of the
      object names file labels in `dataset_dir`
    - an absolute filepath to the object names file. In this case,
      `dataset_dir` has no effect on the location of the file

    If None, the parameter will default to `obj.names`
  * **classes** (*None*) – the list of possible class labels. This does not need
    to be provided if `objects_path` contains the class labels
  * **label_type** ( *"detections"*) – the label format to load. The supported
    values are `("detections", "instances", "polylines")`
  * **mask_size** (*None*) – an optional `(width, height)` at which to render
    each instance mask. Only used when `label_type="instances"`. If
    no mask size is provided then instance masks are rendered
    proportionally to each image’s dimensions
  * **include_all_data** (*False*) – whether to generate samples for all images in
    the data directory (True) rather than only creating samples for
    images with labels (False)
  * **shuffle** (*False*) – whether to randomly shuffle the order in which the
    samples are imported
  * **seed** (*None*) – a random seed to use when shuffling
  * **max_samples** (*None*) – a maximum number of samples to import. By default,
    all samples are imported

**Attributes:**

| [`has_dataset_info`](#fiftyone.utils.yolo.YOLOv4DatasetImporter.has_dataset_info)     | Whether this importer produces a dataset info dictionary.                                                                                                         |
|---------------------------------------------------------------------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| [`has_image_metadata`](#fiftyone.utils.yolo.YOLOv4DatasetImporter.has_image_metadata) | Whether this importer produces [`fiftyone.core.metadata.ImageMetadata`](fiftyone.core.metadata.md#fiftyone.core.metadata.ImageMetadata) instances for each image. |
| [`label_cls`](#fiftyone.utils.yolo.YOLOv4DatasetImporter.label_cls)                   | The [`fiftyone.core.labels.Label`](fiftyone.core.labels.md#fiftyone.core.labels.Label) class(es) returned by this importer.                                       |

**Methods:**

| [`setup`](#fiftyone.utils.yolo.YOLOv4DatasetImporter.setup)()                         | Performs any necessary setup before importing the first sample in the dataset.                      |
|---------------------------------------------------------------------------------------|-----------------------------------------------------------------------------------------------------|
| [`get_dataset_info`](#fiftyone.utils.yolo.YOLOv4DatasetImporter.get_dataset_info)()   | Returns the dataset info for the dataset.                                                           |
| [`close`](#fiftyone.utils.yolo.YOLOv4DatasetImporter.close)(\*args)                   | Performs any necessary actions after the last sample has been imported.                             |
| [`get_media_sources`](#fiftyone.utils.yolo.YOLOv4DatasetImporter.get_media_sources)() | Returns the media-source entries the importing dataset records before any sample is added, or None. |

#### *property* has_dataset_info

Whether this importer produces a dataset info dictionary.

#### *property* has_image_metadata

Whether this importer produces
[`fiftyone.core.metadata.ImageMetadata`](fiftyone.core.metadata.md#fiftyone.core.metadata.ImageMetadata) instances for each image.

#### *property* label_cls

The [`fiftyone.core.labels.Label`](fiftyone.core.labels.md#fiftyone.core.labels.Label) class(es) returned by this
importer.

This can be any of the following:

- a [`fiftyone.core.labels.Label`](fiftyone.core.labels.md#fiftyone.core.labels.Label) class. In this case, the
  importer is guaranteed to return labels of this type
- a list or tuple of [`fiftyone.core.labels.Label`](fiftyone.core.labels.md#fiftyone.core.labels.Label) classes. In
  this case, the importer can produce a single label field of any of
  these types
- a dict mapping keys to [`fiftyone.core.labels.Label`](fiftyone.core.labels.md#fiftyone.core.labels.Label) classes.
  In this case, the importer will return label dictionaries with keys
  and value-types specified by this dictionary. Not all keys need be
  present in the imported labels
- `None`. In this case, the importer makes no guarantees about the
  labels that it may return

#### setup()

Performs any necessary setup before importing the first sample in
the dataset.

This method is called when the importer’s context manager interface is
entered, `DatasetImporter.__enter__()`.

#### get_dataset_info()

Returns the dataset info for the dataset.

By convention, this method should be called after all samples in the
dataset have been imported.

* **Returns:**
  a dict of dataset info

#### close(\*args)

Performs any necessary actions after the last sample has been
imported.

This method is called when the importer’s context manager interface is
exited, `DatasetImporter.__exit__()`.

* **Parameters:**
  **\*args** – the arguments to `DatasetImporter.__exit__()`

#### get_media_sources()

Returns the media-source entries the importing dataset records
before any sample is added, or None.

Only importers of media-reference-backed samples provide these; see
[`fiftyone.utils.lerobot.LeRobotDatasetImporter`](fiftyone.utils.lerobot.md#fiftyone.utils.lerobot.LeRobotDatasetImporter).

### *class* fiftyone.utils.yolo.YOLOv5DatasetImporter(dataset_dir=None, yaml_path=None, split='val', label_type='detections', mask_size=None, include_all_data=False, shuffle=False, seed=None, max_samples=None)

Bases: [`LabeledImageDatasetImporter`](fiftyone.utils.data.importers.md#fiftyone.utils.data.importers.LabeledImageDatasetImporter), [`ImportPathsMixin`](fiftyone.utils.data.importers.md#fiftyone.utils.data.importers.ImportPathsMixin)

Importer for YOLOv5 datasets stored on disk.

See [this page](../user_guide/import_datasets.md#yolov5dataset-import) for format details.

* **Parameters:**
  * **dataset_dir** (*None*) – the dataset directory. If omitted, `yaml_path`
    must be provided
  * **yaml_path** (*None*) – 

    an optional parameter that enables explicit control
    over the location of the dataset YAML file. Can be any of the
    following:
    - a filename like `"dataset.yaml"` specifying the name of the
      YAML file in `dataset_dir`
    - an absolute path to the YAML file. In this case,
      `dataset_dir` has no effect

    If None, the parameter will default to `dataset.yaml`
  * **split** ( *"val"*) – the split to load. Typical values are
    `("train", "val")`
  * **label_type** ( *"detections"*) – the label format to load. The supported
    values are `("detections", "instances", "polylines")`
  * **mask_size** (*None*) – an optional `(width, height)` at which to render
    each instance mask. Only used when `label_type="instances"`. If
    no mask size is provided then instance masks are rendered
    proportionally to each image’s dimensions
  * **include_all_data** (*False*) – whether to generate samples for all images in
    the data directory (True) rather than only creating samples for
    images with labels (False)
  * **shuffle** (*False*) – whether to randomly shuffle the order in which the
    samples are imported
  * **seed** (*None*) – a random seed to use when shuffling
  * **max_samples** (*None*) – a maximum number of samples to import. By default,
    all samples are imported

**Attributes:**

| [`has_dataset_info`](#fiftyone.utils.yolo.YOLOv5DatasetImporter.has_dataset_info)     | Whether this importer produces a dataset info dictionary.                                                                                                         |
|---------------------------------------------------------------------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| [`has_image_metadata`](#fiftyone.utils.yolo.YOLOv5DatasetImporter.has_image_metadata) | Whether this importer produces [`fiftyone.core.metadata.ImageMetadata`](fiftyone.core.metadata.md#fiftyone.core.metadata.ImageMetadata) instances for each image. |
| [`label_cls`](#fiftyone.utils.yolo.YOLOv5DatasetImporter.label_cls)                   | The [`fiftyone.core.labels.Label`](fiftyone.core.labels.md#fiftyone.core.labels.Label) class(es) returned by this importer.                                       |

**Methods:**

| [`setup`](#fiftyone.utils.yolo.YOLOv5DatasetImporter.setup)()                         | Performs any necessary setup before importing the first sample in the dataset.                      |
|---------------------------------------------------------------------------------------|-----------------------------------------------------------------------------------------------------|
| [`get_dataset_info`](#fiftyone.utils.yolo.YOLOv5DatasetImporter.get_dataset_info)()   | Returns the dataset info for the dataset.                                                           |
| [`close`](#fiftyone.utils.yolo.YOLOv5DatasetImporter.close)(\*args)                   | Performs any necessary actions after the last sample has been imported.                             |
| [`get_media_sources`](#fiftyone.utils.yolo.YOLOv5DatasetImporter.get_media_sources)() | Returns the media-source entries the importing dataset records before any sample is added, or None. |

#### *property* has_dataset_info

Whether this importer produces a dataset info dictionary.

#### *property* has_image_metadata

Whether this importer produces
[`fiftyone.core.metadata.ImageMetadata`](fiftyone.core.metadata.md#fiftyone.core.metadata.ImageMetadata) instances for each image.

#### *property* label_cls

The [`fiftyone.core.labels.Label`](fiftyone.core.labels.md#fiftyone.core.labels.Label) class(es) returned by this
importer.

This can be any of the following:

- a [`fiftyone.core.labels.Label`](fiftyone.core.labels.md#fiftyone.core.labels.Label) class. In this case, the
  importer is guaranteed to return labels of this type
- a list or tuple of [`fiftyone.core.labels.Label`](fiftyone.core.labels.md#fiftyone.core.labels.Label) classes. In
  this case, the importer can produce a single label field of any of
  these types
- a dict mapping keys to [`fiftyone.core.labels.Label`](fiftyone.core.labels.md#fiftyone.core.labels.Label) classes.
  In this case, the importer will return label dictionaries with keys
  and value-types specified by this dictionary. Not all keys need be
  present in the imported labels
- `None`. In this case, the importer makes no guarantees about the
  labels that it may return

#### setup()

Performs any necessary setup before importing the first sample in
the dataset.

This method is called when the importer’s context manager interface is
entered, `DatasetImporter.__enter__()`.

#### get_dataset_info()

Returns the dataset info for the dataset.

By convention, this method should be called after all samples in the
dataset have been imported.

* **Returns:**
  a dict of dataset info

#### close(\*args)

Performs any necessary actions after the last sample has been
imported.

This method is called when the importer’s context manager interface is
exited, `DatasetImporter.__exit__()`.

* **Parameters:**
  **\*args** – the arguments to `DatasetImporter.__exit__()`

#### get_media_sources()

Returns the media-source entries the importing dataset records
before any sample is added, or None.

Only importers of media-reference-backed samples provide these; see
[`fiftyone.utils.lerobot.LeRobotDatasetImporter`](fiftyone.utils.lerobot.md#fiftyone.utils.lerobot.LeRobotDatasetImporter).

### *class* fiftyone.utils.yolo.YOLOv4DatasetExporter(export_dir=None, data_path=None, labels_path=None, objects_path=None, images_path=None, export_media=None, rel_dir=None, classes=None, include_confidence=False, use_masks=False, tolerance=2, image_format=None)

Bases: [`LabeledImageDatasetExporter`](fiftyone.utils.data.exporters.md#fiftyone.utils.data.exporters.LabeledImageDatasetExporter), [`ExportPathsMixin`](fiftyone.utils.data.exporters.md#fiftyone.utils.data.exporters.ExportPathsMixin)

Exporter that writes YOLOv4 datasets to disk.

See [this page](../user_guide/export_datasets.md#yolov4dataset-export) for format details.

* **Parameters:**
  * **export_dir** (*None*) – the directory to write the export. This has no
    effect if `data_path`, `objects_path`, and `images_path` are
    absolute paths
  * **data_path** (*None*) – 

    an optional parameter that enables explicit control
    over the location of the exported data and labels. Can be any of
    the following:
    - a folder name like `"data"` or `"data/"` specifying a
      subfolder of `export_dir` in which to export the data and
      labels
    - an absolute directory path in which to export the data and
      labels. In this case, the `export_dir` has no effect on the
      location of the data

    If None, the data will be written into `export_dir` using the
    default folder name
  * **labels_path** (*None*) – 

    an optional parameter that enables explicit
    control over the location of the exported labels. Can be any of the
    following:
    - a folder name like `"labels"` or `"labels/"` specifying the
      location in `export_dir` in which to export the labels
    - an absolute folder path to which to export the labels. In this
      case, the `export_dir` has no effect on the location of
      the labels

    If None, the labels will be written into the same directory as the
    exported media
  * **objects_path** (*None*) – 

    an optional parameter that enables explicit
    control over the location of the object names file. Can be any of
    the following:
    - a filename like `"obj.names"` specifying the location in
      `export_dir` in which to export the object names
    - an absolute filepath to which to export the object names. In
      this case, the `export_dir` has no effect on the location of
      the object names

    If None, the object names will be written into `export_dir`
    using the default filename, unless no media is being exported, in
    which case this file will not be written
  * **images_path** (*None*) – 

    an optional parameter that enables explicit control
    over the location of the image listing file. Can be any of the
    following:
    - a filename like `"images.txt"` specifying the location in
      `export_dir` in which to export the image listing
    - an absolute filepath to which to export the image listing. In
      this case, the `export_dir` has no effect on the location of
      the image listing

    If None, the image listing will be written into `export_dir`
    using the default filename, unless no media is being exported, in
    which case this file will not be written
  * **export_media** (*None*) – 

    controls how to export the raw media. The
    supported values are:
    - `True`: copy all media files into the output directory
    - `False`: don’t export media
    - `"move"`: move all media files into the output directory
    - `"symlink"`: create symlinks to the media files in the output
      directory

    If None, the default value of this parameter will be chosen based
    on the value of the `data_path` parameter
  * **rel_dir** (*None*) – an optional relative directory to strip from each input
    filepath to generate a unique identifier for each image. When
    exporting media, this identifier is joined with `data_path` and
    `labels_path` to generate output paths for each exported image
    and labels file. This argument allows for populating nested
    subdirectories that match the shape of the input paths. The path is
    converted to an absolute path (if necessary) via
    [`fiftyone.core.storage.normalize_path()`](fiftyone.core.storage.md#fiftyone.core.storage.normalize_path)
  * **classes** (*None*) – the list of possible class labels
  * **include_confidence** (*False*) – whether to include detection confidences in
    the export, if they exist
  * **use_masks** (*False*) – whether to export detections based on their
    instance masks rather than their bounding boxes
  * **tolerance** (*2*) – a tolerance, in pixels, when generating approximate
    polylines for the instance masks. Typical values are 1-3 pixels
  * **image_format** (*None*) – the image format to use when writing in-memory
    images to disk. By default, `fiftyone.config.default_image_ext`
    is used

**Attributes:**

| [`requires_image_metadata`](#fiftyone.utils.yolo.YOLOv4DatasetExporter.requires_image_metadata)   | Whether this exporter requires [`fiftyone.core.metadata.ImageMetadata`](fiftyone.core.metadata.md#fiftyone.core.metadata.ImageMetadata) instances for each sample being exported.   |
|---------------------------------------------------------------------------------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| [`label_cls`](#fiftyone.utils.yolo.YOLOv4DatasetExporter.label_cls)                               | The [`fiftyone.core.labels.Label`](fiftyone.core.labels.md#fiftyone.core.labels.Label) class(es) exported by this exporter.                                                         |

**Methods:**

| [`setup`](#fiftyone.utils.yolo.YOLOv4DatasetExporter.setup)()                                                 | Performs any necessary setup before exporting the first sample in the dataset.                                                                                                                  |
|---------------------------------------------------------------------------------------------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| [`export_sample`](#fiftyone.utils.yolo.YOLOv4DatasetExporter.export_sample)(image_or_path, label[, metadata]) | Exports the given sample to the dataset.                                                                                                                                                        |
| [`close`](#fiftyone.utils.yolo.YOLOv4DatasetExporter.close)(\*args)                                           | Performs any necessary actions after the last sample has been exported.                                                                                                                         |
| [`log_collection`](#fiftyone.utils.yolo.YOLOv4DatasetExporter.log_collection)(sample_collection)              | Logs any relevant information about the [`fiftyone.core.collections.SampleCollection`](fiftyone.core.collections.md#fiftyone.core.collections.SampleCollection) whose samples will be exported. |

#### *property* requires_image_metadata

Whether this exporter requires
[`fiftyone.core.metadata.ImageMetadata`](fiftyone.core.metadata.md#fiftyone.core.metadata.ImageMetadata) instances for each sample
being exported.

#### *property* label_cls

The [`fiftyone.core.labels.Label`](fiftyone.core.labels.md#fiftyone.core.labels.Label) class(es) exported by this
exporter.

This can be any of the following:

- a [`fiftyone.core.labels.Label`](fiftyone.core.labels.md#fiftyone.core.labels.Label) class. In this case, the
  exporter directly exports labels of this type
- a list or tuple of [`fiftyone.core.labels.Label`](fiftyone.core.labels.md#fiftyone.core.labels.Label) classes. In
  this case, the exporter can export a single label field of any of
  these types
- a dict mapping keys to [`fiftyone.core.labels.Label`](fiftyone.core.labels.md#fiftyone.core.labels.Label) classes.
  In this case, the exporter can handle label dictionaries with
  value-types specified by this dictionary. Not all keys need be
  present in the exported label dicts
- `None`. In this case, the exporter makes no guarantees about the
  labels that it can export

#### setup()

Performs any necessary setup before exporting the first sample in
the dataset.

This method is called when the exporter’s context manager interface is
entered, `DatasetExporter.__enter__()`.

#### export_sample(image_or_path, label, metadata=None)

Exports the given sample to the dataset.

* **Parameters:**
  * **image_or_path** – an image or the path to the image on disk
  * **label** – an instance of [`label_cls()`](#fiftyone.utils.yolo.YOLOv4DatasetExporter.label_cls), or a dictionary mapping
    field names to [`fiftyone.core.labels.Label`](fiftyone.core.labels.md#fiftyone.core.labels.Label) instances,
    or `None` if the sample is unlabeled
  * **metadata** (*None*) – a [`fiftyone.core.metadata.ImageMetadata`](fiftyone.core.metadata.md#fiftyone.core.metadata.ImageMetadata)
    instance for the sample. Only required when
    [`requires_image_metadata()`](#fiftyone.utils.yolo.YOLOv4DatasetExporter.requires_image_metadata) is `True`

#### close(\*args)

Performs any necessary actions after the last sample has been
exported.

This method is called when the exporter’s context manager interface is
exited, `DatasetExporter.__exit__()`.

* **Parameters:**
  **\*args** – the arguments to `DatasetExporter.__exit__()`

#### log_collection(sample_collection)

Logs any relevant information about the
[`fiftyone.core.collections.SampleCollection`](fiftyone.core.collections.md#fiftyone.core.collections.SampleCollection) whose samples will
be exported.

Subclasses can optionally implement this method if their export format
can record information such as the
[`fiftyone.core.collections.SampleCollection.info()`](fiftyone.core.collections.md#fiftyone.core.collections.SampleCollection.info) of the
collection being exported.

By convention, this method must be optional; i.e., if it is not called
before the first call to [`export_sample()`](#fiftyone.utils.yolo.YOLOv4DatasetExporter.export_sample), then the exporter must
make do without any information about the
[`fiftyone.core.collections.SampleCollection`](fiftyone.core.collections.md#fiftyone.core.collections.SampleCollection) (which may not be
available, for example, if the samples being exported are not stored in
a collection).

* **Parameters:**
  **sample_collection** – the
  [`fiftyone.core.collections.SampleCollection`](fiftyone.core.collections.md#fiftyone.core.collections.SampleCollection) whose
  samples will be exported

### *class* fiftyone.utils.yolo.YOLOv5DatasetExporter(export_dir=None, split='val', data_path=None, labels_path=None, yaml_path=None, export_media=None, rel_dir=None, classes=None, include_confidence=False, use_masks=False, tolerance=2, image_format=None, include_path=True)

Bases: [`LabeledImageDatasetExporter`](fiftyone.utils.data.exporters.md#fiftyone.utils.data.exporters.LabeledImageDatasetExporter), [`ExportPathsMixin`](fiftyone.utils.data.exporters.md#fiftyone.utils.data.exporters.ExportPathsMixin)

Exporter that writes YOLOv5 datasets to disk.

See [this page](../user_guide/export_datasets.md#yolov5dataset-export) for format details.

* **Parameters:**
  * **export_dir** (*None*) – the directory to write the export. This has no
    effect if `data_path`, `labels_path`, and `yaml_path` are
    absolute paths
  * **split** ( *"val"*) – the split being exported. Typical values are
    `("train", "val")`
  * **data_path** (*None*) – 

    an optional parameter that enables explicit control
    over the location of the exported media. Can be any of the
    following:
    - a folder name like `"images"` or `"images/"` specifying a
      subfolder of `export_dir` in which to export the images
    - an absolute directory path in which to export the images. In
      this case, the `export_dir` has no effect on the location of
      the images

    If None, the data will be written into `export_dir` using the
    default folder name
  * **labels_path** (*None*) – 

    an optional parameter that enables explicit
    control over the location of the exported labels. Can be any of the
    following:
    - a folder name like `"labels"` or `"labels/"` specifying the
      location in `export_dir` in which to export the labels
    - an absolute folder path to which to export the labels. In this
      case, the `export_dir` has no effect on the location of
      the labels

    If None, the labels will be written into `export_dir` using the
    default folder name
  * **yaml_path** (*None*) – 

    an optional parameter that enables explicit control
    over the location of the dataset YAML file. Can be any of the
    following:
    - a filename like `"dataset.yaml"` specifying the location in
      `export_dir` to write the YAML file
    - an absolute filepath to which to write the YAML file. In this
      case, the `export_dir` has no effect on the location of
      the image listing

    If None, the dataset YAML file will be written into `export_dir`
    using the default filename, unless no media is being exported, in
    which case this file will not be written
  * **export_media** (*None*) – 

    controls how to export the raw media. The
    supported values are:
    - `True`: copy all media files into the output directory
    - `False`: don’t export media
    - `"move"`: move all media files into the output directory
    - `"symlink"`: create symlinks to the media files in the output
      directory

    If None, the default value of this parameter will be chosen based
    on the value of the `data_path` parameter
  * **rel_dir** (*None*) – an optional relative directory to strip from each input
    filepath to generate a unique identifier for each image. When
    exporting media, this identifier is joined with `data_path` and
    `labels_path` to generate output paths for each exported image
    and labels file. This argument allows for populating nested
    subdirectories that match the shape of the input paths. The path is
    converted to an absolute path (if necessary) via
    [`fiftyone.core.storage.normalize_path()`](fiftyone.core.storage.md#fiftyone.core.storage.normalize_path)
  * **classes** (*None*) – the list of possible class labels
  * **include_confidence** (*False*) – whether to include detection confidences in
    the export, if they exist
  * **use_masks** (*False*) – whether to export detections based on their
    instance masks rather than their bounding boxes
  * **tolerance** (*2*) – a tolerance, in pixels, when generating approximate
    polylines for the instance masks. Typical values are 1-3 pixels
  * **image_format** (*None*) – the image format to use when writing in-memory
    images to disk. By default, `fiftyone.config.default_image_ext`
    is used
  * **include_path** (*True*) – whether to include the directory name containing
    the YAML file in the `path` key of the exported YAML

**Attributes:**

| [`requires_image_metadata`](#fiftyone.utils.yolo.YOLOv5DatasetExporter.requires_image_metadata)   | Whether this exporter requires [`fiftyone.core.metadata.ImageMetadata`](fiftyone.core.metadata.md#fiftyone.core.metadata.ImageMetadata) instances for each sample being exported.   |
|---------------------------------------------------------------------------------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| [`label_cls`](#fiftyone.utils.yolo.YOLOv5DatasetExporter.label_cls)                               | The [`fiftyone.core.labels.Label`](fiftyone.core.labels.md#fiftyone.core.labels.Label) class(es) exported by this exporter.                                                         |

**Methods:**

| [`setup`](#fiftyone.utils.yolo.YOLOv5DatasetExporter.setup)()                                                 | Performs any necessary setup before exporting the first sample in the dataset.                                                                                                                  |
|---------------------------------------------------------------------------------------------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| [`export_sample`](#fiftyone.utils.yolo.YOLOv5DatasetExporter.export_sample)(image_or_path, label[, metadata]) | Exports the given sample to the dataset.                                                                                                                                                        |
| [`close`](#fiftyone.utils.yolo.YOLOv5DatasetExporter.close)(\*args)                                           | Performs any necessary actions after the last sample has been exported.                                                                                                                         |
| [`log_collection`](#fiftyone.utils.yolo.YOLOv5DatasetExporter.log_collection)(sample_collection)              | Logs any relevant information about the [`fiftyone.core.collections.SampleCollection`](fiftyone.core.collections.md#fiftyone.core.collections.SampleCollection) whose samples will be exported. |

#### *property* requires_image_metadata

Whether this exporter requires
[`fiftyone.core.metadata.ImageMetadata`](fiftyone.core.metadata.md#fiftyone.core.metadata.ImageMetadata) instances for each sample
being exported.

#### *property* label_cls

The [`fiftyone.core.labels.Label`](fiftyone.core.labels.md#fiftyone.core.labels.Label) class(es) exported by this
exporter.

This can be any of the following:

- a [`fiftyone.core.labels.Label`](fiftyone.core.labels.md#fiftyone.core.labels.Label) class. In this case, the
  exporter directly exports labels of this type
- a list or tuple of [`fiftyone.core.labels.Label`](fiftyone.core.labels.md#fiftyone.core.labels.Label) classes. In
  this case, the exporter can export a single label field of any of
  these types
- a dict mapping keys to [`fiftyone.core.labels.Label`](fiftyone.core.labels.md#fiftyone.core.labels.Label) classes.
  In this case, the exporter can handle label dictionaries with
  value-types specified by this dictionary. Not all keys need be
  present in the exported label dicts
- `None`. In this case, the exporter makes no guarantees about the
  labels that it can export

#### setup()

Performs any necessary setup before exporting the first sample in
the dataset.

This method is called when the exporter’s context manager interface is
entered, `DatasetExporter.__enter__()`.

#### export_sample(image_or_path, label, metadata=None)

Exports the given sample to the dataset.

* **Parameters:**
  * **image_or_path** – an image or the path to the image on disk
  * **label** – an instance of [`label_cls()`](#fiftyone.utils.yolo.YOLOv5DatasetExporter.label_cls), or a dictionary mapping
    field names to [`fiftyone.core.labels.Label`](fiftyone.core.labels.md#fiftyone.core.labels.Label) instances,
    or `None` if the sample is unlabeled
  * **metadata** (*None*) – a [`fiftyone.core.metadata.ImageMetadata`](fiftyone.core.metadata.md#fiftyone.core.metadata.ImageMetadata)
    instance for the sample. Only required when
    [`requires_image_metadata()`](#fiftyone.utils.yolo.YOLOv5DatasetExporter.requires_image_metadata) is `True`

#### close(\*args)

Performs any necessary actions after the last sample has been
exported.

This method is called when the exporter’s context manager interface is
exited, `DatasetExporter.__exit__()`.

* **Parameters:**
  **\*args** – the arguments to `DatasetExporter.__exit__()`

#### log_collection(sample_collection)

Logs any relevant information about the
[`fiftyone.core.collections.SampleCollection`](fiftyone.core.collections.md#fiftyone.core.collections.SampleCollection) whose samples will
be exported.

Subclasses can optionally implement this method if their export format
can record information such as the
[`fiftyone.core.collections.SampleCollection.info()`](fiftyone.core.collections.md#fiftyone.core.collections.SampleCollection.info) of the
collection being exported.

By convention, this method must be optional; i.e., if it is not called
before the first call to [`export_sample()`](#fiftyone.utils.yolo.YOLOv5DatasetExporter.export_sample), then the exporter must
make do without any information about the
[`fiftyone.core.collections.SampleCollection`](fiftyone.core.collections.md#fiftyone.core.collections.SampleCollection) (which may not be
available, for example, if the samples being exported are not stored in
a collection).

* **Parameters:**
  **sample_collection** – the
  [`fiftyone.core.collections.SampleCollection`](fiftyone.core.collections.md#fiftyone.core.collections.SampleCollection) whose
  samples will be exported

### *class* fiftyone.utils.yolo.YOLOAnnotationWriter

Bases: `object`

Class for writing annotations in YOLO-style TXT format.

**Methods:**

| [`write`](#fiftyone.utils.yolo.YOLOAnnotationWriter.write)(label, txt_path, labels_map_rev[, ...])   | Writes the labels to disk.   |
|------------------------------------------------------------------------------------------------------|------------------------------|

#### write(label, txt_path, labels_map_rev, dynamic_classes=False, include_confidence=False, use_masks=False, tolerance=2)

Writes the labels to disk.

* **Parameters:**
  * **label** – a [`fiftyone.core.labels.Detections`](fiftyone.core.labels.md#fiftyone.core.labels.Detections) or
    [`fiftyone.core.labels.Polylines`](fiftyone.core.labels.md#fiftyone.core.labels.Polylines)
  * **txt_path** – the path to write the annotation TXT file
  * **labels_map_rev** – a dictionary mapping class label strings to target
    integers
  * **dynamic_classes** (*False*) – whether to dynamically add new labels to
    `labels_map_rev`
  * **include_confidence** (*False*) – whether to include confidences in the
    export, if they exist
  * **use_masks** (*False*) – whether to export detections based on their
    instance masks rather than their bounding boxes
  * **tolerance** (*2*) – a tolerance, in pixels, when generating approximate
    polylines for the instance masks. Typical values are 1-3 pixels

### fiftyone.utils.yolo.load_yolo_annotations(txt_path, classes, label_type='detections', mask_size=None, frame_size=None)

Loads the YOLO-style annotations from the given TXT file.

The txt file should be a space-delimited file where each row corresponds
to an object in one the following formats:

```default
# Detections
<target> <x-center> <y-center> <width> <height>
<target> <x-center> <y-center> <width> <height> <confidence>

# Instance segmentations or polygons
<target> <x1> <y1> <x2> <y2> <x3> <y3> ...
```

where `target` is the zero-based integer index of the object class label
from `classes` and all coordinates are expressed as relative values in
`[0, 1] x [0, 1]`.

* **Parameters:**
  * **txt_path** – the path to the annotations TXT file
  * **classes** – the list of class label strings
  * **label_type** ( *"detections"*) – the label format to load. The supported
    values are `("detections", "instances", "polylines")`
  * **mask_size** (*None*) – an optional `(width, height)` at which to render
    each instance mask. Only used when `label_type="instances"`
  * **frame_size** (*None*) – the `(width, height)` of the frame containing the
    annotations. Only used when `label_type="instances"` and no
    `mask_size` is provided
* **Returns:**
  a [`fiftyone.core.labels.Detections`](fiftyone.core.labels.md#fiftyone.core.labels.Detections) or
  [`fiftyone.core.labels.Polylines`](fiftyone.core.labels.md#fiftyone.core.labels.Polylines)