CDN hyperparameters

[zen-d]

@fcjian Hi, thanks for your great work.

I would like to know when using CDN, how to determine these hyperparameters for virtual depth. Could you please explain more?

[fcjian]

As shown in Figure 5, the final depth is sampled from the real depth, so the range of the real depth (i.e., [0, d_r]) must contain the range of the final depth (i.e., [2, 54]m).
In the paper, we set d_v and f_v to 54m and 800 pixels (i.e. less than the minimum focal length of the nuScenes cameras). Namely, f_r > f_v, which can deduce d_r > d_v = 54m. Therefore, the range of the real depth can contain the range of the final depth for all the nuScenes cameras.