Contextual images

Contextual images of the task

Contextual images are additional images that provide context or additional information related to the primary image.

Use them to add extra contextual about the object to improve the accuracy of annotation.

Contextual images are available for 2D and 3D tasks.

See:

Folder structure

To add contextual images to the task, you need to organize the images folder.

Before uploading the archive to CVAT, do the following:

  1. In the folder with the images for annotation, create a folder: related_images.
  2. Add to the related_images a subfolder with the same name as the primary image to which it should be linked.
  3. Place the contextual image(s) within the subfolder created in step 2.
  4. Add folder to the archive.
  5. Create task.

Data format

Example file structure for 2D and 3D tasks:

  root_directory
    image_1_to_be_annotated.jpg
    image_2_to_be_annotated.jpg
    related_images/
      image_1_to_be_annotated_jpg/
        context_image_for_image_1.jpg
      image_2_to_be_annotated_jpg/
        context_image_for_image_2.jpg
     subdirectory_example/
        image_3_to_be_annotated.jpg
         related_images/
          image_3_to_be_annotated_jpg/
             context_image_for_image_3.jpg
 root_directory
    pointcloud/
      image_1_to_be_annotated.pcd
      image_2_to_be_annotated.pcd
    related_images/
      image_1_to_be_annotated_pcd/
        context_image_for_image_1.jpg
      image_2_to_be_annotated_pcd/
        context_image_for_image_2.jpg
 /any_directory
    pointcloud.pcd
    pointcloud.jpg
/any_other_directory
    /any_subdirectory
        pointcloud.pcd
        pointcloud.png
 /image_00
    /data
        /0000000000.png
        /0000000001.png
        /0000000002.png
        /0000000003.png
/image_01
    /data
        /0000000000.png
        /0000000001.png
        /0000000002.png
        /0000000003.png
/image_02
    /data
        /0000000000.png
        /0000000001.png
        /0000000002.png
        /0000000003.png
/image_N
    /data
        /0000000000.png
        /0000000001.png
        /0000000002.png
        /0000000003.png
/velodyne_points
    /data
        /0000000000.bin
        /0000000001.bin
        /0000000002.bin
        /0000000003.bin
  • For KITTI: image_00, image_01, image_02, image_N, (where N is any number <= 12) are context images.
  • For 3D option 3: a regular image file placed near a .pcd file with the same name is considered to be a context image.

For more general information about 3D data formats, see 3D data formats.

Contextual images

The maximum amount of contextual images is twelve.

By default they will be positioned on the right side of the main image.

Note: By default, only three contextual images will be visible.

contex_images_1

When you add contextual images to the set, small toolbar will appear on the top of the screen, with the following elements:

Element Description
contex_images_4 Fit views. Click to restore the layout to its original appearance.

If you’ve expanded any images in the layout, they will returned to their original size.

This won’t affect the number of context images on the screen.

contex_images_5 Add new image. Click to add context image to the layout.
contex_images_6 Reload layout. Click to reload layout to the default view.

Note, that this action can change the number of context images resetting them back to three.

Each context image has the following elements:

contex_images_2

Element Description
1 Full screen. Click to expand the contextual image in to the full screen mode.

Click again to revert contextual image to windowed mode.

2 Move contextual image. Hold and move contextual image to the other place on the screen.

contex_images_3

3 Name. Unique contextual image name
4 Select contextual image. Click to open a horisontal listview of all available contextual images.

Click on one to select.

5 Close. Click to remove image from contextual images menu.
6 Extend Hold and pull to extend the image.