Why there is an additional channel when N_importance > 0?

[FreemanG]

Hi, thanks for you excellent work.

What's the 5th channel uesd for when N_importance > 0?

nonrigid_nerf/train.py

Line 593 in 5187abf

output_ch = 5 if args.N_importance > 0 else 4

[edgar-tr]

That's just a carry-over from the original source code: https://github.com/yenchenlin/nerf-pytorch/blob/master/run_nerf.py#L187 . My guess is that it's for some experiment to predict some kind of hint for importance sampling. In any case, the fifth channel isn't used anywhere, I just didn't bother to remove it.

[FreemanG]

Thanks for your quick reply.