Image vs Point Cloud Coordinates

The axes for point clouds have completely different meanings to the axes in images. The diagram below shows the image axes in blue and the point cloud axes in orange.

Some important things to note about images:

• The coordinate values in an image are always positive.
• The origin is located on the upper left hand corner.
• The coordinates are integer values.

Things to note about point cloud coordinates:

• The coordinate values in point cloud can be positive or negative.
• The coordinates can take on real numbered values.
• The positive x axis represents forward.
• The positive y axis represents left.
• The positive z axis represents up.