Point cloud cuboid annotation

There are 3 methods to label cuboids in 3D pointclouds - Magic Select (Lasso), One-click annotation and Click-to-place. Depending on the use-case, you may find one method most suitable than the others. We describe all of them below.

The draw cuboid tool and the labels section below it

One Click annotation

When the Draw cuboid tool is selected, you can see a small yellow circle around points as you move over them.

Using this method, you can label an object with just one click! To use it:

1. Choose a label for the object from the left sidebar.

2. Select the Draw cuboid tool from the left sidebar.

3. As you move your mouse over the pointcloud, you should now see a small yello circle around the points as you hover over them.

4. Find a point that belongs to the object, make sure you don't accidentally select a point behind the object.

5. Hold the ctrl key on the keyboard and click on the point.

6. The cuboid should now be drawn.

This method works best when a lot of the points of an object are visible, since it uses clustering to predict the shape of the object. If the object is very sparse, the other methods will work better.

Magic Select

One click annotation works by using a technique called clustering. In some cases, where points of an object are far apart, this may not work. In such cases, you can use the Magic select tool to draw cuboids. Here is how it works:

1. Choose a label for the object from the left sidebar.

2. Select the Draw cuboid tool from the left sidebar.

3. Hold you right mouse button and draw a rough outline slightly inside the object.

4. The cuboid should now be drawn

Click to place

If neither of the two methods described above work well, you can also place a cuboid of specified dimensions anywhere in the point cloud. To do this, simply hold Shift and click anywhere in the point cloud.

If you expect your objects to roughly be of the same size - for example, if you are labeling boxes in a warehouse - you can specify the default dimensions when setting up the label ontology. If these reference sizes are set, all cuboids of that label will be drawn with the same reference size. If the sizes are not set, a default size of 1m x 1m x 1m will be used.

Editing a cuboid

Once drawn you have a few options to edit the cuboid

Using top/side/front views

The top, side and front view of an object. The cuboid can be edited by dragging the corners of each plane.

When you select an object, it's top, side and front views are shown at the bottom. You can click and drag the corners of these planes to change the dimensions of the cuboid. This is the easiest way to update a drawn cuboid

Using the resize panel

The resize panel comes up when you select an object.

When an object is selected, a resize panel appears over the pointcloud. You can use this to resize, rotate as well as move the cuboid.

Step size Sometimes you may want to make really large or really precise changes. Using the text box on the right side of each section, you can change the step size for every button press. Setting a lower value will help you make precise changes. Making the step size large will allow you to make large changes quickly.

Cuboid size section The first two rows in the panel are for updating the length, width and height of a cuboid. There are 6 sets of +/- buttons for the 6 faces if the cuboid. For e.g. The set of buttons in the first column and second row, refers to the bottom face of the cuboid.

Rotation section The third row allows you to rotate the cuboid in the X, Y and Z axes, in anti-clockwise( + buttons ) and clockwise( - buttons ) directions. At any point, clicking on the Reset button will reset all rotations and bring the cuboid back to 0° in all axes. The default step size is 2° - which means that for each press of the buttons, the cuboid will rotate by 2°. You can change that by entering a new value in the step size text box.

Translation section This section allows you to move the cuboid in X, Y and Z axes.

Marking forward facing face

Use the buttons in the Forward face section to change the face of an object

To mark the front facing face(side) of a cuboid, use the Forward face section in the resize panel. Once marked, the front face will be highlighted.

Using Keyboard shortcuts

All of the operations listed above can also be performed using convenient keyboard shortcuts. You view a list of the available shortcuts by clicking on the Shortcuts icon at the top, as shown in the image below. You can also view a list of all the shortcuts here.

The keyboard shortcuts icon