Refactor image processing and cutout functionalities

- Updated the naming convention for upscaled images to include underscores and file extensions.
- Renamed properties related to cutout pixel size to point spacing for clarity.
- Adjusted alpha region calculations to use a half-alpha threshold for better accuracy.
- Enhanced the handling of foreground mesh masks to consider half-alpha values.
- Introduced new functions for unbounded selections and cutout images, ensuring proper handling of source and selection images.
- Improved test coverage for cutout functionalities, including bounds mapping and alpha preservation.
- Updated tests to reflect changes in naming conventions and functionality adjustments.

src/anyimage/server/geometry/cutout.py

@@ -186,7 +186,7 @@ def alpha_regions(alpha, max_resolution=512, threshold=0.5):
     sampled_size = tuple(max(1, round(value * scale)) for value in source_size)
     if sampled_size != source_size:
         values = _resize_alpha(values, sampled_size)
-    mask = values > round(255.0 * threshold)
+    mask = values >= 255.0 * threshold
     regions = mask_regions(mask)
     scale_x = source_size[0] / sampled_size[0]
     scale_y = source_size[1] / sampled_size[1]

src/anyimage/server/geometry/grid_mesh.py

@@ -116,7 +116,7 @@ def foreground_mesh_mask(foreground_path, depth_shape):
             resample=Image.Resampling.BILINEAR,
         )
         alpha = alpha.filter(ImageFilter.GaussianBlur(radius=0.75))
-        return np.asarray(alpha) > 0
+        return np.asarray(alpha) >= round(255.0 * 0.5)
 
 
 def confidence_percentile_threshold(depth, confidence, percentile):