If using Windows, we recommend using 7-Zip to unzip the exported labels.

Label Coordinates

In the JSON format, label coordinates are normalized to be between 0 and 1. This means that the corners of the frame or image correspond to the coordinates (1,1), (1,0), (0,0), (0,1) regardless of frame dimensions.

To get the pixel values of normalized coordinates:

  • The x and h coordinates of a label should be multiplied by the pixel width of the frame or image.
  • The y and w coordinates of a label should be multiplied by the pixel height of the frame or image.

Format of Exported Labels

The last_edited_by and last_edited_at fields are updated only when the label or its nested attributes are modified in the Label Editor. If the SDK is used to update the label, these fields must be updated manually.

The tables below provide descriptions of all values contained JSON format exports.

Exports of label versions for which the data unit was deleted vary from the examples shown below - the data_type is deleted, while image groups and image sequences only contain a single data_unit.

Single Images

The export contains a list of JSON objects, with each JSON object representing a single data unit and containing detailed information for all exported labels.

The example below describes all the keys for a single exported data unit.

[
    {
        "classification_answers": {},
        "created_at": "2025-01-07 16:12:23",
        "data_hash": "f3132c00-069f-4a95-8e21-30c13078d84d",
        "data_title": "Image3.jpg",
        "data_type": "image",
        "data_units": {
        },
        "dataset_hash": "3c35b0f2-64fc-4a58-9b9d-f7181d73f1e5",
        "dataset_title": "New Welsh Whales",
        "is_image_sequence": null,
        "is_valid": true,
        "label_hash": "0f5a5e62-a3e0-4481-932f-1093f7c1d170",
        "label_status": "LABEL_IN_PROGRESS",
        "last_edited_at": "2025-01-07 16:12:23",
        "object_actions": {},
        "object_answers": {},
        "video_link": null
    }
]
KeyDescriptionNotes
label_hashThe Label Row hashThe ‘hash’ represents a unique identifier
created_atTime and date the label was created
last_edited_atTime and date the label was last edited
dataset_hashThe Dataset’s hashThe ‘hash’ represents a unique identifier
data_typeThe data unit’s file formatAlways “video” for videos
is_image_sequence”true” when the data unit is an image sequenceAlways “null” for images
video_linkContains a private cloud URL for videosAlways “null” for images
data_unitsList of all files the data unit is composed ofDetails of the export information for `data_units“ can be found below.
object_answersAll the attributes in this data unitThe object attributes are identified using their hash
classification_answersAll the classifications in a particular data unitThe classification labels are identified using their hash
object_actionsThe number of states a dynamic attribute can be in.A change in state occurs each time the attribute answer changes. The objectHash within the object_actions is the attribute answer’s ID.
label_statusIndicates whether the data unit has been labeled.
export_historyContains a record of the export history for this data unitExporting labels to confirm export history generates an export history entry.
export_hashThe hash for this particular export instanceThe ‘hash’ represents a unique identifier
exported_atThe date and time when a particular export instance took place.

Image Groups & Image Sequences

Confused about the difference between image groups and image sequences? See our documentation here to learn about different data types in Encord.

The export contains a list of JSON objects, with each JSON object representing a single image group or image sequence, and containing detailed information for all exported labels.

The example below describes all the keys for a single exported data unit.

[
  {
    "label_hash": "781dd0ff-e4c2-48f1-bcd1-09f2f0756701",
    "created_at": "2023-03-23 11:42:14",
    "last_edited_at": "2023-10-02 13:53:03",
    "dataset_hash": "4a4141ed-8d8b-4518-b1f7-97a5c53e992b",
    "dataset_title": "cooking_image_sequences",
    "data_title": "image-group-67bdc95d",
    "data_hash": "9c588f63-ad87-4987-a074-06ba0d6980cd",
    "data_type": "image_group",
    "is_image_sequence": null,
    "image_sequence_link": "www.my-private-cloud.com/how-to-make-apple-pie.mp4",
    "data_units": { },
    "classification_answers": { },
    "object_actions": { },
    "label_status": "LABELLED",
    "export_history": [
      {
        "export_hash": "02b56519-9664-4e38-9713-4817a5caf648",
        "exported_at": "Mon, 02 Oct 2023 14:35:30 UTC",
        "user_email": "david.babuschkin@encord.com"
      },
      {
        "export_hash": "2e0ee531-41ce-4ce9-a859-b6b47697e5d2",
        "exported_at": "Mon, 02 Oct 2023 13:47:45 UTC",
        "user_email": "david.babuschkin@encord.com"
      }
    ],
    "export_hash": "02b56519-9664-4e38-9713-4817a5caf648",
    "exported_at": "Mon, 02 Oct 2023 14:35:30 UTC",
  }
]
KeyDescriptionNotes
label_hashThe Label Row hashThe ‘hash’ represents a unique identifier
created_atTime and date the label was created
last_edited_atTime and date the label was last edited
dataset_hashThe dataset’s hashThe ‘hash’ represents a unique identifier
data_typeThe data unit’s file formatAlways “img_group” for image groups and image sequences
is_image_sequencetrue when the data unit is an image sequencefalse for all other types of data, including image groups. This is what distinguishes image groups and image sequences in your export
video_linkContains a link to file storage location if file is a videoAlways “null” for image groups and image sequences
data_unitsList of all files the data unit is composed ofDetails of the export information for data units can be found below.
object_answersAll the attributes in this data unitThe object attributes are identified using their hash
classification_answersAll the classifications in a particular data unitThe classification labels are identified using their hash
object_actionsThe number of states a dynamic attribute can be in.A change in state occurs each time the attribute answer changes. The objectHash within the object_actions is the attribute answer’s ID.
label_statusIndicates whether the data unit has been labeled.
export_historyContains a record of the export history for this data unitExporting labels to confirm export history generates an export history entry.
export_hashThe hash for this particular export instanceThe ‘hash’ represents a unique identifier
exported_atThe date and time when a particular export instance took place.


Videos

The export contains a list of JSON objects, with each JSON object representing a single data unit and containing detailed information for all exported labels.

The example below describes all the keys for a single exported data unit.


[
  {
    "label_hash": "781dd0ff-e4c2-48f1-bcd1-09f2f0756701",
    "created_at": "2023-03-23 11:42:14",
    "last_edited_at": "2023-10-02 13:53:03",
    "dataset_hash": "4a4141ed-8d8b-4518-b1f7-97a5c53e992b",
    "dataset_title": "cooking_videos",
    "data_title": "how-to-make-apple-pie.mp4",
    "data_hash": "9c588f63-ad87-4987-a074-06ba0d6980cd",
    "data_type": "video",
    "is_image_sequence": null,
    "video_link": "www.my-private-cloud.com/how-to-make-apple-pie.mp4",
    "data_units": { },
    "classification_answers": { },
    "object_actions": { },
    "label_status": "LABELLED",
    "export_history": [
      {
        "export_hash": "02b56519-9664-4e38-9713-4817a5caf648",
        "exported_at": "Mon, 02 Oct 2023 14:35:30 UTC",
        "user_email": "david.babuschkin@encord.com"
      },
      {
        "export_hash": "2e0ee531-41ce-4ce9-a859-b6b47697e5d2",
        "exported_at": "Mon, 02 Oct 2023 13:47:45 UTC",
        "user_email": "david.babuschkin@encord.com"
      }
    ],
    "export_hash": "02b56519-9664-4e38-9713-4817a5caf648",
    "exported_at": "Mon, 02 Oct 2023 14:35:30 UTC",
  }
]

KeyDescriptionNotes
label_hashThe Label Row hashThe ‘hash’ represents a unique identifier
created_atTime and date the label was created
last_edited_atTime and date the label was last edited
dataset_hashThe Dataset’s hashThe ‘hash’ represents a unique identifier
data_typeThe data unit’s file formatAlways “video” for videos
is_image_sequence”true” when the data unit is an image sequenceAlways “null” for videos
video_linkLink to the video saved on your private cloudAlways “null” for all other file types
data_unitsList of all files the data unit is composed ofDetails of the export information for `data_units“ can be found below.
object_answersAll the attributes in this data unitThe object attributes are identified using their hash
classification_answersAll the classifications in a particular data unitThe classification labels are identified using their hash
object_actionsThe number of states a dynamic attribute can be in.A change in state occurs each time the attribute answer changes. The objectHash within the object_actions is the attribute answer’s ID.
label_statusIndicates whether the data unit has been labeled.
export_historyContains a record of the export history for this data unitExporting labels to confirm export history generates an export history entry.
export_hashThe hash for this particular export instanceThe ‘hash’ represents a unique identifier
exported_atThe date and time when a particular export instance took place.


DICOM

The export contains a list of JSON objects, with each JSON object representing a single data unit and containing detailed information for all exported labels.

The following example describes all the keys for a single exported data unit.


[
  {
    "label_hash": "781dd0ff-e4c2-48f1-bcd1-09f2f0756701",
    "created_at": "2023-03-23 11:42:14",
    "last_edited_at": "2023-10-02 13:53:03",
    "dataset_hash": "4a4141ed-8d8b-4518-b1f7-97a5c53e992b",
    "dataset_title": "BB: CT thin slices",
    "data_title": "9c58",
    "data_hash": "9c588f63-ad87-4987-a074-06ba0d6980cd",
    "data_type": "dicom",
    "is_image_sequence": null,
    "video_link": null,
    "data_units": { },
    "classification_answers": { },
    "object_actions": { },
    "label_status": "LABELLED",
    "export_history": [
      {
        "export_hash": "02b56519-9664-4e38-9713-4817a5caf648",
        "exported_at": "Mon, 02 Oct 2023 14:35:30 UTC",
        "user_email": "david.babuschkin@encord.com"
      },
      {
        "export_hash": "2e0ee531-41ce-4ce9-a859-b6b47697e5d2",
        "exported_at": "Mon, 02 Oct 2023 13:47:45 UTC",
        "user_email": "david.babuschkin@encord.com"
      }
    ],
    "export_hash": "02b56519-9664-4e38-9713-4817a5caf648",
    "exported_at": "Mon, 02 Oct 2023 14:35:30 UTC",
  }
]

KeyDescriptionNotes
label_hashThe Label Row hashThe ‘hash’ represents a unique identifier
created_atTime and date the label was created
last_edited_atTime and date the label was last edited
dataset_hashThe dataset’s hashThe ‘hash’ represents a unique identifier
data_typeThe data unit’s file formatAlways “dicom” in a DICOM series
is_image_sequence”true” when the data unit is an image sequenceAlways “null” for a DICOM series
video_linkLink to the video or image sequenceAlways “null” for a DICOM series
data_unitsList of all files the data unit is composed ofDetails of the export information for `data_units“ can be found below.
object_answersAll the object attributes in this data unitThe object attribute are identified using their hash
classification_answersAll the classifications in a particular data unitThe classification labels are identified using their hash
object_actionsThe number of states a dynamic attribute can be in.A change in state occurs each time the attribute answer changes. The objectHash within the object_actions is the attribute answer’s ID.
label_statusIndicates whether the data unit has been labeled.
export_historyContains a record of the export history for the data unitExporting labels to confirm export history generates an export history entry.
export_hashThe hash for this particular export instanceThe ‘hash’ represents a unique identifier
exported_atThe date and time when a particular export instance took place.


Audio

The export contains a list of JSON objects, with each JSON object representing a single data unit and containing detailed information for all exported labels.

The example below describes all the keys for a single exported data unit.

[
    {
        "classification_answers": {},
        "created_at": "2025-01-09 15:58:20",
        "data_hash": "ffd810f4-f503-46ac-b54f-bd5f8057f440",
        "data_title": "beautiful-tune.mp3",
        "data_type": "audio",
        "data_units": {
        },
        "dataset_hash": "3696067a-7e68-4d25-b09d-517877e13f06",
        "dataset_title": "Music",
        "is_image_sequence": null,
        "is_valid": true,
        "label_hash": "a384bab6-9443-4932-a862-c5c18f39c88b",
        "label_status": "LABELLED",
        "last_edited_at": "2025-01-09 15:58:35",
        "object_actions": {},
        "object_answers": {}
    }
]
KeyDescriptionNotes
label_hashThe Label Row hashThe ‘hash’ represents a unique identifier
created_atTime and date the label was created
last_edited_atTime and date the label was last edited
dataset_hashThe Dataset’s hashThe ‘hash’ represents a unique identifier
data_typeThe data unit’s file formatAlways “video” for videos
is_image_sequence”true” when the data unit is an image sequenceAlways “null” for images
video_linkContains a private cloud URL for videosAlways “null” for images
data_unitsList of all files the data unit is composed ofDetails of the export information for `data_units“ can be found below.
object_answersAll the attributes in this data unitThe object attributes are identified using their hash
classification_answersAll the classifications in a particular data unitThe classification labels are identified using their hash
object_actionsThe number of states a dynamic attribute can be in.A change in state occurs each time the attribute answer changes. The objectHash within the object_actions is the attribute answer’s ID.
label_statusIndicates whether the data unit has been labeled.
export_historyContains a record of the export history for this data unitExporting labels to confirm export history generates an export history entry.
export_hashThe hash for this particular export instanceThe ‘hash’ represents a unique identifier
exported_atThe date and time when a particular export instance took place.

Text

The export contains a list of JSON objects, with each JSON object representing a single data unit and containing detailed information for all exported labels.

The example below describes all the keys for a single exported data unit.

[
    {
        "classification_answers": {},
        "created_at": "2025-01-11 14:58:20",
        "data_hash": "ffd810f4-f503-46ac-b54f-bd5f8057f440",
        "data_title": "encord-website.html",
        "data_type": "plain_text",
        "data_units": {
        },
        "dataset_hash": "3696067a-7e68-4d25-b09d-517877e13f06",
        "dataset_title": "HTML Text",
        "is_image_sequence": null,
        "is_valid": true,
        "label_hash": "a384bab6-9443-4932-a862-c5c18f39c88b",
        "label_status": "LABELLED",
        "last_edited_at": "2025-01-09 15:58:35",
        "object_actions": {},
        "object_answers": {}
    }
]
KeyDescriptionNotes
label_hashThe Label Row hashThe ‘hash’ represents a unique identifier
created_atTime and date the label was created
last_edited_atTime and date the label was last edited
dataset_hashThe Dataset’s hashThe ‘hash’ represents a unique identifier
data_typeThe data unit’s file formatAlways “video” for videos
is_image_sequence”true” when the data unit is an image sequenceAlways “null” for images
video_linkContains a private cloud URL for videosAlways “null” for images
data_unitsList of all files the data unit is composed ofDetails of the export information for `data_units“ can be found below.
object_answersAll the attributes in this data unitThe object attributes are identified using their hash
classification_answersAll the classifications in a particular data unitThe classification labels are identified using their hash
object_actionsThe number of states a dynamic attribute can be in.A change in state occurs each time the attribute answer changes. The objectHash within the object_actions is the attribute answer’s ID.
label_statusIndicates whether the data unit has been labeled.
export_historyContains a record of the export history for this data unitExporting labels to confirm export history generates an export history entry.
export_hashThe hash for this particular export instanceThe ‘hash’ represents a unique identifier
exported_atThe date and time when a particular export instance took place.

Ontology Shapes

Exports contain the Ontology shape coordinates used to create the label.

Exporting Bitmasks

Bitmask labels are exported as rleStrings. See our SDK documentation to learn how to decode an rleString.

We strongly recommend exporting Bitmask labels using the Encord SDK. Bitmasks are exported in the JSON format.

Exporting Labels using the SDK

Go here to learn how to export JSON files from Encord’s Python SDK. Reach out to us to if you need to export COCO labels.

Label Branches

The branch associated with the labels is specified using the branch_name key.

The main branch is always displayed first and is identified by the following value:

"branch_name": "main"