Spaces:
Running on Zero
Running on Zero
| """Depth edits (Sec. 4.3, Appendix H): the renderer reads an explicit depth map, so replacing it changes how the image | |
| is focused without retraining. Every function returns a depth map (1, H, W) in [0, 1] to render with.""" | |
| import torch | |
| def depth_at(depth, x, y): | |
| """D at pixel (x, y), clamped to the image: the focal depth D_f of a focal point.""" | |
| _, h, w = depth.shape | |
| return depth[0, max(0, min(h - 1, int(round(y)))), max(0, min(w - 1, int(round(x))))] | |
| def two_focal_planes(depth, focal_depth_a, focal_depth_b): | |
| """D' = D_A + min(|D - D_A|, |D - D_B|): every pixel is blurred by its distance to the nearer of two focal planes. | |
| Render D' with focal depth D_A. If adding the distance would clip more pixels at 1 than subtracting it would clip at | |
| 0 (a far plane A), it is subtracted instead: adding it to D_A = 1 would make the whole image sharp.""" | |
| da, db = float(focal_depth_a), float(focal_depth_b) | |
| distance = torch.minimum((depth - da).abs(), (depth - db).abs()) | |
| subtract = int((da - distance < 0).sum()) < int((da + distance > 1).sum()) | |
| return (da - distance if subtract else da + distance).clamp(0, 1) | |
| def tilt_shift(height, width, row, slope=3.0, band=0.06, device="cpu"): | |
| """A vertical ramp with a flat band of half-height `band` centred at `row` (fractions of the height): a horizontal | |
| band stays sharp and blur grows above and below it. Render it with the focal point at (W / 2, row * H).""" | |
| yy = torch.linspace(0, 1, height, device=device).view(height, 1).expand(height, width) | |
| dy = (yy - row).abs().sub(band).clamp(min=0) * torch.sign(yy - row) | |
| return (0.5 + slope * dy / 2).clamp(0, 1)[None] | |