What are the axes directions for the spatial coordinates in `SpatialImgDetection`? I was expecting it to follow camera coordinate conventions, that is: * X points to the right * Y points down * Z points forward However, in tests I found Y to point **up** — Y coordinate values are positive above the camera's center, and negative below. Is this by design? If yes, what is the rationale?

Hi xperroni! The OAK camera uses a right-handed (Cartesian) coordinate system for all spatial coordinates. This means that: * X points to the right * Y points up * Z points forward This is indeed by design. The rationale behind this is to follow the standard convention for a right-handed coordinate system. In this system, if you point your index finger in the direction of the X axis, and your middle finger in the direction of the Y axis, your thumb will point in the direction of the Z axis. Sources: - [Spatial Coordinate System - MobileNet Spatial Detection Network](https://docs.luxonis.com/projects/api/en/latest/components/nodes/mobilenet_spatial_detection_network.rst/#spatial-coordinate-system) - [Spatial Coordinate System - Spatial Location Calculator](https://docs.luxonis.com/projects/api/en/latest/components/nodes/spatial_location_calculator/#spatial-coordinate-system) - [Spatial Coordinate System - Yolo Spatial Detection Network](https://docs.luxonis.com/projects/api/en/latest/components/nodes/yolo_spatial_detection_network/#spatial-coordinate-system) Hope this helps! :) Best, Luxonis BOT

SpatialImgDetection - axes directions?

xperroni

What are the axes directions for the spatial coordinates in SpatialImgDetection? I was expecting it to follow camera coordinate conventions, that is:

X points to the right
Y points down
Z points forward

However, in tests I found Y to point up — Y coordinate values are positive above the camera's center, and negative below.

Is this by design? If yes, what is the rationale?

jakaskerl

Hi xperroni
OAK camera uses left-handed (Cartesian) coordinate system for all spatial coordiantes.
This is because the center of the image is the origin, so it makes sense intuitively that x is right, y is up and z is depth.

Thanks,
Jaka

crs287

Are there any figures showing these coordinate frames to make sure I don't have any misunderstandings?