NeRF Ray Sample Count

Problem

Count the network evaluations for all rays of one NeRF image.

Each of the h * w pixels casts one ray, and every ray is sampled at n_coarse coarse points plus n_fine fine points. Return h * w * (n_coarse + n_fine).

Hint

The fine network is queried per ray as a whole, not per coarse interval.

Test cases

case 1

in: [100,100,64,128]

expected: 1920000

case 2

in: [32,32,32,0]

expected: 32768

case 3

in: [1,1,2,3]

expected: 5

case 4

in: [224,224,64,64]

expected: 6422528

Starter codePython

def nerf_sample_count(h, w, n_coarse, n_fine):
    # Your code here
    pass

4 test cases · run your code against them in the editor