Meaning of the bd_factor

[zgojcic]

Hi,

thank you for open-sourcing the code of this great work! I was wondering if you could provide some insight on why the depth from COLMAP is scaled using the bd_factor and how to appropriately set its value?

Should bd_factor be scene-dependent?

Thank you for your help. Zan

[dunbar12138]

Because all of the z values and boundaries are scaled using bd_factor. We need to keep consistent between COLMAP depth and NeRF settings. Overall, bd_factor is a hyperparameter that adjusts the magnitude of the scene size. In my experiment, I don't change it except for some special needs.

[dnlwbr]

What if you want to use the depth values from a sensor instead of COLMAP depth? Does bd_factor then have to be adjusted or does it remain the same as well?