Controls

left mouse click Add marker / region corner

backspace Remove last placed region corner

esc Cancel region creation

left mouse double click Complete polygon region

enter Complete polygon region

left mouse double click (on region) Edit region vertices

right mouse click (on annotation) Edit annotation

left mouse drag (on annotation) Drag annotation

ctrl + left mouse click (on annotation) Remove annotation

1, 2 ... 8 Change annotation class

c, v, b Change annotation tool

z, x Increase/decrease focus

ctrl + mouse wheel Increase/decrease focus

shift + mouse wheel Rotate image

mouse wheel Zoom in / out

left mouse drag Pan image

Session

A collaboration session can be started from the Session menu, which can be opened from the right side of the page. You can either create a new session or join an existing one. When collaborating, all participants see the same annotations and can update them in real time. By clicking on another collaborator's name in the session menu, you can move your viewport to match theirs. By ticking the checkbox next to their name, you can automatically follow them.

Reverting sessions

Changes made in a session are automatically stored on the server. These changes can be reverted by opening the Revert changes menu. This menu lists the most recent changes made and at what time they were made. By choosing one of these versions and clicking the button in the menu, all changes back to and including the selected version are reverted.

Loading images

Open the Image browser to see a list of available images on the server. Click one of the images to view it.

Navigating images

The image viewer can be navigated with the mouse. The mouse wheel is used to zoom in and out of the image. Holding down the left mouse button and dragging it inside the image viewer pans the image. The focus can be changed either by pressing the Up and Down buttons on the right side of the page, pressing the z and x buttons on the keyboard, or holding down the ctrl key while scrolling the mouse wheel. In addition, the image can be rotated by holding down the shift key and scrolling the mouse wheel.

Annotations

There are three types of annotations that can be added: markers, rectangles and polygons. To select which type of annotation should be placed, a tool can be selected either by pressing the buttons in the menu to the right or by pressing the c, v or b keys on the keyboard. To select which class an annotation should be placed as, press the buttons to the right or use the number keys. Once an annotation has been placed, it can be moved by dragging it with the mouse, and it can be edited and commented on by right clicking it. Holding down the ctrl key and clicking an annotation removes it. The viewport can be moved to an annotation by clicking the Move to button in the list of annotations on the right.

Markers

With the marker tool active, you can place markers in the viewport by clicking with left mouse button. In order to interact with a placed marker, the marker tool has to be active.

Rectangles

With the rectangle tool active, you can place a rectangular region by first clicking where one corner of the region should be, and then clicking where the opposite corner should be. Once the first corner has been placed, it can be cancelled by pressing either esc or backspace. In order to interact with a placed rectangular region, either the rectangle or polygon tool has to be active.

Polygons

With the polygon tool active, you can place a polygonal region by clicking where each corner should be. In order to complete the region, you can either double click or press enter. In order to undo the last placed corner of the polygon, you can press backspace, and in order to cancel the entire polygon, you can press esc. In order to interact with a placed polygonal region, either the rectangle or polygon tool has to be active.

Saving annotations

Annotations can be saved to a file on the local machine by pressing the Export button. Annotations that have been saved can be loaded into the image by pressing the Import button.

A filter can be used to specify which annotations are shown in the viewport and annotation list. Filters can be specified through a combination of keys, values, comparisons, and combinations. Filtering can also be used in the same way in the session picker.

Keys

Keys specify the properties of the annotations that should be considered when filtering the annotations. The available keys are:

• class – The class the annotation belongs to.
• author – The name of the user who created the annotation.
• comments – The number of comments an annotation has.
• bookmarked – Whether or not an annotation is bookmarked.
• region – Whether or not an annotation is a region.
• marker – Whether or not an annotation is a marker.
• x – The x position of the annotation's centroid.
• y – The y position of the annotation's centroid.
• z – The z position of the annotation.
• prediction – The class probability of the annotation.

The session picker uses a different set of keys for filtering sessions. These keys are:

• name – The name of the session.
• author – The name of the user who created the session.
• created – The time at which the session was created.
• updated – The time of the last update in the session.
• annotations – The number of annotations in the session.
• comments – The number of comments in the session.
• users – The current number of active users in the session.

Values

Values specify what the annotation properties should be compared to in the filter. A value can be a boolean, in which case it is specified as true or false, a null object, in which case it is specified as null, a string, in which case a quotation mark should be placed on either side of the value, or a number, which can be either an integer or a real number. In addition, the value can be specified as a key, in which case two properties of the annotation are compared to each other.

Comparisons

Comparisons specify the relationships between keys and values that should be fulfilled for an annotation to pass a filter. The available comparisons are:

• [key] = [value] – A key is exactly equal to a given value.
• [key] > [value] – A key is greater than a given value.
• [key] < [value] – A key is less than a given value.

Combinations

Combinations are used to combine or modify smaller parts of the filter. The available combinations are:

• [subfilter] AND [subfilter] – Both subfilters must pass.
• [subfilter] OR [subfilter] – One of the subfilters must pass.
• NOT [subfilter] – The result of the subfilter is negated.
• ([subfilter]) – The subfilter is evaluated in isolation.

Examples

The following examples show some of the filters that can be specified:

• class = "HSIL" – Annotations belonging to the HSIL class.
• x > 50000 – Annotations with an x position greater than 50000.
• NOT author = "Bob" – Annotations made by people other than Bob.
• author = "Bob" AND bookmarked = true – Bookmarked annotations made by Bob.
• bookmarked = true OR comments > 0 – Annotations that have either been bookmarked or commented on.
• bookmarked = true AND (class = "Other" OR comments > 0) – Bookmarked annotations that either have the class "Other" or have been commented on.
• x > y – Annotations where the x position is greater than the y position.
• prediction = null – Annotations where the prediction has not been defined.