1 files changed, 140 insertions, 0 deletions
diff --git a/modules/upscaler_utils.py b/modules/upscaler_utils.py
new file mode 100644
index 00000000..f5cb92d5
--- /dev/null
+++ b/modules/upscaler_utils.py
@@ -0,0 +1,140 @@
+import logging
+from typing import Callable
+
+import numpy as np
+import torch
+import tqdm
+from PIL import Image
+
+from modules import images, shared, torch_utils
+
+logger = logging.getLogger(__name__)
+
+
+def upscale_without_tiling(model, img: Image.Image):
+    img = np.array(img)
+    img = img[:, :, ::-1]
+    img = np.ascontiguousarray(np.transpose(img, (2, 0, 1))) / 255
+    img = torch.from_numpy(img).float()
+
+    param = torch_utils.get_param(model)
+    img = img.unsqueeze(0).to(device=param.device, dtype=param.dtype)
+
+    with torch.no_grad():
+        output = model(img)
+
+    output = output.squeeze().float().cpu().clamp_(0, 1).numpy()
+    output = 255. * np.moveaxis(output, 0, 2)
+    output = output.astype(np.uint8)
+    output = output[:, :, ::-1]
+    return Image.fromarray(output, 'RGB')
+
+
+def upscale_with_model(
+    model: Callable[[torch.Tensor], torch.Tensor],
+    img: Image.Image,
+    *,
+    tile_size: int,
+    tile_overlap: int = 0,
+    desc="tiled upscale",
+) -> Image.Image:
+    if tile_size <= 0:
+        logger.debug("Upscaling %s without tiling", img)
+        output = upscale_without_tiling(model, img)
+        logger.debug("=> %s", output)
+        return output
+
+    grid = images.split_grid(img, tile_size, tile_size, tile_overlap)
+    newtiles = []
+
+    with tqdm.tqdm(total=grid.tile_count, desc=desc) as p:
+        for y, h, row in grid.tiles:
+            newrow = []
+            for x, w, tile in row:
+                logger.debug("Tile (%d, %d) %s...", x, y, tile)
+                output = upscale_without_tiling(model, tile)
+                scale_factor = output.width // tile.width
+                logger.debug("=> %s (scale factor %s)", output, scale_factor)
+                newrow.append([x * scale_factor, w * scale_factor, output])
+                p.update(1)
+            newtiles.append([y * scale_factor, h * scale_factor, newrow])
+
+    newgrid = images.Grid(
+        newtiles,
+        tile_w=grid.tile_w * scale_factor,
+        tile_h=grid.tile_h * scale_factor,
+        image_w=grid.image_w * scale_factor,
+        image_h=grid.image_h * scale_factor,
+        overlap=grid.overlap * scale_factor,
+    )
+    return images.combine_grid(newgrid)
+
+
+def tiled_upscale_2(
+    img,
+    model,
+    *,
+    tile_size: int,
+    tile_overlap: int,
+    scale: int,
+    device,
+    desc="Tiled upscale",
+):
+    # Alternative implementation of `upscale_with_model` originally used by
+    # SwinIR and ScuNET.  It differs from `upscale_with_model` in that tiling and
+    # weighting is done in PyTorch space, as opposed to `images.Grid` doing it in
+    # Pillow space without weighting.
+    b, c, h, w = img.size()
+    tile_size = min(tile_size, h, w)
+
+    if tile_size <= 0:
+        logger.debug("Upscaling %s without tiling", img.shape)
+        return model(img)
+
+    stride = tile_size - tile_overlap
+    h_idx_list = list(range(0, h - tile_size, stride)) + [h - tile_size]
+    w_idx_list = list(range(0, w - tile_size, stride)) + [w - tile_size]
+    result = torch.zeros(
+        b,
+        c,
+        h * scale,
+        w * scale,
+        device=device,
+    ).type_as(img)
+    weights = torch.zeros_like(result)
+    logger.debug("Upscaling %s to %s with tiles", img.shape, result.shape)
+    with tqdm.tqdm(total=len(h_idx_list) * len(w_idx_list), desc=desc) as pbar:
+        for h_idx in h_idx_list:
+            if shared.state.interrupted or shared.state.skipped:
+                break
+
+            for w_idx in w_idx_list:
+                if shared.state.interrupted or shared.state.skipped:
+                    break
+
+                in_patch = img[
+                    ...,
+                    h_idx : h_idx + tile_size,
+                    w_idx : w_idx + tile_size,
+                ]
+                out_patch = model(in_patch)
+
+                result[
+                    ...,
+                    h_idx * scale : (h_idx + tile_size) * scale,
+                    w_idx * scale : (w_idx + tile_size) * scale,
+                ].add_(out_patch)
+
+                out_patch_mask = torch.ones_like(out_patch)
+
+                weights[
+                    ...,
+                    h_idx * scale : (h_idx + tile_size) * scale,
+                    w_idx * scale : (w_idx + tile_size) * scale,
+                ].add_(out_patch_mask)
+
+                pbar.update(1)
+
+    output = result.div_(weights)
+
+    return output