Object selection in an image

This section describes how to add the area selection editor to an image and speed up task completion with shortcuts. If you just need to insert a picture, read the Inserting images section.

Add the area selection editor

To allow Tolokers to select areas in pictures, use the field.image-annotation component.

{
  "view": {
    "type": "field.image-annotation",
    "data": {
      "type": "data.output",
      "path": "path"
    },
    "image": "url"
  }
}
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Configure labeling modes

The component offers three labeling modes: rectangle, polygon, and point markup. All three modes are available by default. You can choose to use just one or two of them.

{
    "shapes": {
      "rectangle": true
    }
}
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Classify areas

You can allow Tolokers to select objects by type. For example, you may want all cars selected in the picture to be labeled as one type, and all road signs as another.

{
  "labels": [{
      "label": "Option 1",
      "value": "value1"
    },
    {
      "label": "Option 2",
      "value": "value2"
    }
  ]
}
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For each new object of the labels property, a button is added to the editor that allows Tolokers to select the corresponding area type. Different values of the value property let Tolokers label areas with different colors.

Add keyboard shortcuts

To help Tolokers work faster, you can add keyboard shortcuts using the plugin.field.image-annotation.hotkeys component. Shortcuts can be assigned to the up and down arrows (up,down), numbers, and Latin letters.

If you install the shortcut plugin without assigning keys, they are assigned automatically.

You can change them as described below. If you don't need some of the shortcuts, leave their value fields empty.

{
    "type": "plugin.field.image-annotation.hotkeys",
    "labels": [
        "1",
        "2"
    ]
}
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Create a task

To create a template for area selection tasks, use the following components:

• field.image-annotation: To add the area selection editor.
• plugin.field.image-annotation.hotkeys: To add keyboard shortcuts.
• view.text: To add a description to the task.
• condition.required: To make sure that a Toloker selected at least one area.
• plugin.toloka: To customize the task layout.

Last updated: February 10, 2023