Some doubts about Sharpness and other tricks

[lzhnb]

Hi! I have some doubts about the sharpness.

I've not seen the sharpness in other NeRF projects. It seems to be obtained via processing the 2D input images.
Are there any references?

Otherwise, I'm analyzing the importance of different tricks used: linear color and random background color.
Are there any other important tricks?

The nerf_random_image_pos_training which generates xy_pdf and image_idx which generates img_pdf confuse me.

Thanks :)

[lzhnb]

Oh, #130 solved my doubts about sharpness. It can be seen as an (edge)importance detector.