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bmild / nerf

Code release for NeRF (Neural Radiance Fields)
http://tancik.com/nerf
MIT License
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number of output channels #27

Closed kwea123 closed 4 years ago

kwea123 commented 4 years ago

Normally the output has only 4 channels: rgb and sigma, but here it is set to 5 when N_importance>0, which is always the case in default experiments.

https://github.com/bmild/nerf/blob/c39def3944c982aa7aabeacdd2e856c07da39b9e/run_nerf.py#L388

So what does this 5th output do? I checked the code of raw2outputs and it seems the 5th element is never accessed, so it means the network has a redundant output?

bmild commented 4 years ago

You're right, this is leftover functionality from an experiment that didn't go anywhere (trying to use an additional 5th channel to predict weighting in the coarse model that was distinct from the sigma opacity channel).