def reverse_diffuse(self, x_t: torch.Tensor, t: torch.Tensor, noise: torch.Tensor) -> torch.Tensor:
        """
        Get original image from noisy version under timestep t.
        """
        assert noise.shape == x_t.shape, "noise must have same shape as x_t"
        t = t.view(-1, *[1 for _ in range(len(x_t.shape) - 1)])
        x_0 = (x_t - (self.sigma_min + (1 - self.sigma_min) * t) * noise) / (1 - t)
        return x_0

        Get original image from noisy version under timestep t.
        
trellis/trainers/flow_matching/flow_matching.py