【BUG ?】 Problems about the background loss when self_bg=False

[Dawn-LX]

Hi, I am confused about the calculation of bg_loss. here:
https://github.com/qiuyu96/CoDeF/blob/137f16c5423d484846857327597bf65c06b92994/train.py#L329

first of all, what does self_bg mean? Next, when self_bg=False, it seems that we are computing the mse loss between grid (coordinate values) and rgb values. I suppose this is wrong.

if self.hparams.bg_loss:
    mk1 = torch.logical_not(mk_t)
    if self.hparams.self_bg:
        grid_flattened = rgbs_flattend
    else:
        grid_flattened = rearrange(grid, 'b n c -> (b n) c')
        grid_flattened = torch.cat(
            [grid_flattened, grid_flattened[:, :1]], -1)

if self.hparams.bg_loss and self.hparams.mask_dir:
    loss = loss + self.hparams.bg_loss * self.color_loss(
        results[mk1], grid_flattened[mk1])

although all experiments use self_bg=True according to the config. I'm just curious about the config self_bg, what does it mean? and what are we doing when self_bg=False ?