I am trying to better understand what is the depth from a depth map. For simplicity sake, I am running the `spatial`*`location`*`calculator.py` The `Z` value is the distance from the Image Frame correct? I have been thinking `Z` is the distance from the sensor. But seeing [this diagram](https://docs.luxonis.com/projects/api/en/latest/components/nodes/stereo_depth/#measuring-real-world-object-dimensions) has me re-thinking my understanding. I am starting to thinking the distance I have been expecting Z to be is Euclidean distance. For example, I expected areas that are further from the center of my image to have a larger Z value but this was not the case. The target scene in question was quiet flat so my Z was uniform throughout the image. Can anyone provide insight on this please?

@"jakaskerl"#1112 Thank you! I appreciate it!

Depth Interpetation

wamj45

I am trying to better understand what is the depth from a depth map. For simplicity sake, I am running the spatiallocationcalculator.py The Z value is the distance from the Image Frame correct? I have been thinking Z is the distance from the sensor. But seeing this diagram has me re-thinking my understanding. I am starting to thinking the distance I have been expecting Z to be is Euclidean distance.

For example, I expected areas that are further from the center of my image to have a larger Z value but this was not the case. The target scene in question was quiet flat so my Z was uniform throughout the image.

Can anyone provide insight on this please?

jakaskerl

wamj45
The Z coordinate is always the shortest distance from camera xy plane to object and is therefore a normal to the plane. This is because an object is represented in camera's coordinate frame which is Cartesian.

distance will be calculated as euclidian distance (sqrt), but Z will remain xy invariant.

Thanks,
Jaka

wamj45

@jakaskerl
Thank you! I appreciate it!