feat(api): support invert_mask flag for /inpaint and /inpaint-multipart (selected area removed by default)

api/main.py

@@ -48,6 +48,7 @@ def bearer_auth(authorization: Optional[str] = Header(default=None)) -> None:
 class InpaintRequest(BaseModel):
     image_id: str
     mask_id: str
+    invert_mask: bool = True  # True => selected/painted area is removed
 
 
 @app.get("/")
@@ -141,7 +142,7 @@ def inpaint(req: InpaintRequest, _: None = Depends(bearer_auth)) -> Dict[str, st
     mask_img = Image.open(file_store[req.mask_id]["path"])  # may be RGB/gray/RGBA
     mask_rgba = _load_rgba_mask_from_image(mask_img)
 
-    result = process_inpaint(np.array(img_rgba), mask_rgba)
+    result = process_inpaint(np.array(img_rgba), mask_rgba, invert_mask=req.invert_mask)
     result_name = f"output_{uuid.uuid4().hex}.png"
     result_path = os.path.join(OUTPUT_DIR, result_name)
     Image.fromarray(result).save(result_path)
@@ -162,7 +163,7 @@ def inpaint_url(req: InpaintRequest, request: Request, _: None = Depends(bearer_
     mask_img = Image.open(file_store[req.mask_id]["path"])  # may be RGB/gray/RGBA
     mask_rgba = _load_rgba_mask_from_image(mask_img)
 
-    result = process_inpaint(np.array(img_rgba), mask_rgba)
+    result = process_inpaint(np.array(img_rgba), mask_rgba, invert_mask=req.invert_mask)
     result_name = f"output_{uuid.uuid4().hex}.png"
     result_path = os.path.join(OUTPUT_DIR, result_name)
     Image.fromarray(result).save(result_path)
@@ -177,6 +178,7 @@ def inpaint_multipart(
     image: UploadFile = File(...),
     mask: UploadFile = File(...),
     request: Request = None,
+    invert_mask: bool = True,
     _: None = Depends(bearer_auth),
 ) -> Dict[str, str]:
     # Load in-memory
@@ -184,7 +186,7 @@ def inpaint_multipart(
     m = Image.open(mask.file)
     mask_rgba = _load_rgba_mask_from_image(m)
 
-    result = process_inpaint(np.array(img), mask_rgba)
+    result = process_inpaint(np.array(img), mask_rgba, invert_mask=invert_mask)
     result_name = f"output_{uuid.uuid4().hex}.png"
     result_path = os.path.join(OUTPUT_DIR, result_name)
     Image.fromarray(result).save(result_path)