Object tracking

Create object tracks to track them across frames and use automatic interpolation to fasten the annotation process.

To track cuboids across frames, draw use the cuboid tracking mode when drawing objects.

Tracking cuboids with the cuboid track tool

Simply select the Draw cuboid track tool from the left toolbar, and draw a cuboid using any of the methods described here.

When you draw a cuboid in tracking mode, a cuboid will also be automatically copied to the subsequent frames. All these cuboids will have the same object ID.

The object card for a track, as it appears in the right sidebar

Ending a track

To mark the end of a track, simply click on the End track icon - this is the right most icon the tool panel in the bottom section of the card, as shown above.

Labeling static objects

If an object appears in multiple frames, but its position relative to the ego-vehicle does not change, you can mark it as a static object by clicking on the lock icon located at the center in the tool panel in the bottom section of the card.

Navigation

A frame in which you make any changes to an object is called a key-frame. You can navigate between the key-frames by using the next and previous buttons, located either side of the lock icon.

The frames on either side of these navigation icons, take to the first and last frame of the track.

Automatic Interpolation

Automatic interpolation is automatically started as soon as you label at-least 2 frames in a track.

Interpolation can be used in two labeling flows:

Labeling flow 1

1. Label the first frame in which an object appears.

2. Adjust its position/size in the next frame.

3. Automatic interpolation will now adjust the cuboid in all subsequent frames.

4. If you adjustments in any of the subsequent frames, other frames will also be automatically adjusted.

Labeling flow 2

1. Label the first frame in which an object appears.

2. Skip a few frames.

3. Adjust the cuboid/size after a few frames.

4. All frames in between will be automatically adjusted.

5. Any subsequent frames will also be adjusted automatically.