What's this?

This is a platform for managing an image dataset. It's designed to make it easy for anyone to upload images, annotate them, and for people who need images to search for them. There's also a JSON API for automating tasks. It's also free software under the GNU AGPLv3.

Querying for pictures

The query format is based on YAML and used to query for pictures in the system.

Structure

The root can have 3 keys:

• want: A list of rules that the images must satisfy. If not provided, no filtering is done.

• exclude: A list of rules that the images must not satisfy. If not provided, no filtering is done.

• include_obsolete: If true the query may return images with a designated replacement. If false (default) this won't be possible.

want and exclude are lists of rules. Each rule is a dictionary with a single key (this is to allow multiple rules of the same kind). Accepted rules are:

• has: [object1, object2, ...]: The image must contain any of the objects in the list, or a descendant of any of them.

• has_object: [object1, object2, ...]: The image must contain any of the objects in the list.

• nature: [nature1, nature2, ...]: The image must have one of the natures in the list. Natures are strings like "photo" that indicate the source of the image.

• licence: [licence1, licence2, ...]: The image must have one of the licences in the list. If possible, licence IDs are SPDX identifiers, non-standard ones are prefixed with X-.

• author: [author1, author2, ...]: The image's author's username must be in the list.

• title: query: Search for titles (ilike).

• description: query: Search for descriptions (ilike).

• origin_url: query: Search for origin URLs. The query matches the beginning of the URL excluding the protocol. (like commons.wikimedia.org)

• above_width: width: The image must have a width greater than or equal to the given value, in pixels.

• above_height: height: The image must have a height greater than or equal to the given value, in pixels.

• below_width: width: The image must have a width less than or equal to the given value, in pixels.

• below_height: height: The image must have a height less than or equal to the given value, in pixels.

• before_date: timestamp: The image must have been uploaded before the given Unix timestamp.

• after_date: timestamp: The image must have been uploaded after the given Unix timestamp.

• in_gallery: [gallery1, gallery2, ...]: The image must be in any of the galleries (by ID) in the list.

• above_rating: rating: The image must have a rating greater than or equal to the given value (1-5 stars). Images with no rating are included; use above_rating_count: 1 to exclude them.

• below_rating: rating: The image must have a rating less than or equal to the given value (1-5 stars).

• above_rating_count: count: The image must have at least the given rating count.

• below_rating_count: count: The image must have at most the given rating count.

• above_region_count: count: The image must have at least the given number of regions.

• below_region_count: count: The image must have at most the given number of regions.

• copied_from: [image1, image2, ...]: The image must be a copy of an image in the images in the list (by ID).

ordering, offset and limit can be specified as query parameters in the URL. ordering can be one of date-desc, date-asc, title-asc, title-desc, number-regions-desc, number-regions-asc, random. offset and limit are integers that specify the number of images to skip and the maximum number of images to return, respectively.

Example

# Restrictions for queried images
want:
   # This means that the image must contain both rules, so both a cat and a dog
   - has_object: ["Cat (Felis catus)"]
   - has_object: ["Dog (Canis lupus familiaris)"]
   # Or we can put them in a list to mean that the image can contain any of the
   # objects in the list
   - has_object: ["Grass", "Flower"]
   # So the image must contain a cat and a dog, as well as either grass or
   # a flower
   # The following rule restricts the images to those with a certain source,
   # like a camera or a drawing; omitting this rule means that the images can
   # be of any source
   - nature: ["photo", "computer-3d-art"]
   # The following rule restricts the images to those with a certain licence
   - licence: ["CC-BY-1.0", "CC-BY-2.0", "CC-BY-3.0", "CC-BY-4.0", "CC0-1.0",
               "Unlicense", "WTFPL", "MIT", "BSD-2-Clause", "BSD-3-Clause",
               "Apache-2.0", "X-informal-attribution", "X-informal-do-anything",
               "X-public-domain-old", "X-public-domain"]
# Prohibitions for queried images
exclude:
   # This means that the image must not contain any of the objects in the list
   - has_object: ["Human"]
   # This excludes images uploaded before the given date
   - before_date: 1546300800
   # This requires images to have a minimum resolution
   - below_width: 800
   - below_height: 600
# In summary, we want images that contain both a cat and a dog, either a grass
# or a flower, but not a human, taken after 2019-01-01, must be a photo or a
# 3D render, must carry one of certain permissive licences and have a resolution
# of at least 800x600 pixels.

You will get a list of JSON dictionaries with the following keys:

• id which is the picture's numeric ID.

• title which is the picture's title.

• description which is the picture's description.

• author which is the picture's author's username.

• origin_url which is the picture's origin URL.

• timestamp which is the Unix time at which the picture was posted.

• width and height which are the picture's dimensions, in pixels.

• file_format which is the picture's MIME type.

• nature which is the picture's nature.

• licences which is a list of licence identifiers.

• replaces which is the ID of the picture replaced by this one, if any.

• replaced_by which is the ID of the picture's replacement, if any.

• regions which represents the picture's annotations in the format described below.

• download which is the URL of the image file.

If you query the endpoint /api/picture/<id>/ you will also get:

• rating_average which is the average rating of the picture from one to five stars.

• rating_count which is the number of ratings of each grade.

This is done to avoid processing ratings when they aren't needed.

Raw annotation data format

The client sends raw data for image annotations in a JSON format which is a list of shapes. Each shape is a dictionary with the following keys:

• type: The type of the shape which can be:

  • bbox (bounding box, rectangle)

  • polygon

  • polyline

  • point

• shape: The shape data. Its format depends on the shape type:

  • For bbox it is a dictionary with keys x, y, w, h: {"x": x, "y": y, "w": w, "h": h}

  • For polygon and polyline it is a list of points; each point is a dictionary with keys x and y: [{"x": x1, "y": y1}, {"x": x2, "y": y2}, ...] The only difference between polygon and polyline is that the former is supposed to be closed so the last point is connected to the first one.

  • For point it is a dictionary with keys x and y: {"x": x, "y": y}

  • All coordinates are floating-point numbers in the range [0, 1] and relative to the image size, with the origin in the top-left corner.

• object: The ID of the type of object (label) depicted in the shape. This ID is a human-readable string that must be registered in the system before being used on shapes.

The server sends the same data back to the client, to use to show the existing annotations for an image.

Example

[
   {
       "type": "bbox",
       "shape": {"x": 0.1, "y": 0.1, "w": 0.5, "h": 0.5},
       "object": "Cat (Felis catus)"
   },
   {
       "type": "polygon",
       "shape": [{"x": 0, "y": 0}, {"x": 1, "y": 0}, {"x": 0, "y": 1}],
       "object": "Slice of pizza margherita"
   },
   {
       "type": "point",
       "shape": {"x": 0.5, "y": 0.5},
       "object": "Cat (Felis catus) - left eye"
   }
]

Authenticating with the API

Your HTTP client must support cookies.

POST to /api/login with a JSON body containing keys username and password.

POST to /api/logout to clear the session; you can also just delete the cookie on your own.

User registration isn't supported by the API to prevent spam; use the HTML form.

Uploading from the API

You can upload pictures from the API if you're logged in. POST to /api/upload with a form data containing a key json with the value being a JSON dictionary with title, description, origin_url, licence (list of IDs), nature (ID), and a file file that is your image. The JSON can also have a key annotations if you want to prefill them — check above for the format.

/api/picture/<id>/update allows you to pass title, description, origin_url, licence_ids and nature_id in a JSON body to change an existing picture.

Other endpoints

/api/licence/ provides a dictionary of the licences with the keys being the ID and the value being another dictionary with keys title, free (whether it respects the Four Freedoms) and pinned which indicates if it is at the top of the list.

/api/licence/<id>/ provides more details for the particular licence, including id, title, description, info_url which links to a page with information about the licence, legalese_url which links to the actual legal text, free, pinned and logo_url.

/api/nature/ provides a dictionary of natures of the form id: description.

/api/user/ provides information about users with the key being the name and the value being a dictionary with the admin boolean. It uses offset and limit.

/api/user/<username>/ provides a dictionary with the user's id, admin status and joined date.

POST to /api/picture/<id>/rate with a JSON body with a key rating will put a star rating on the picture. To delete the rating call it with a false value.

POST to /api/picture/<id>/delete will delete the picture.

POST to /api/picture/<id>/put-file with a form payload containing a file key will replace the picture's file with what was provided.

/api/gallery/<id> will give metadata about the gallery in JSON: id, title, description, owner and users. To get the pictures you can use a query.

POST to /api/gallery/<id>/edit with keys title and description in JSON to update the gallery metadata.

POST to /api/new-gallery creates a new gallery with keys title and description in the JSON.

POST to /api/gallery/<id>/add-picture with a JSON dictionary containing a key picture_id will add the picture. /api/gallery/<id>/add-picture will do the reverse.

POST to /api/gallery/<id>/users/add with a JSON dictionary containing a key username will trust an user, /api/gallery/<id>/users/remove will do the reverse.

Other information

The global file size limit is 64 MiB. The server will return a 413 error if exceeded.