mask tự động giữ nguyên vùng SP/người, chỉ edit background

backend/app/api/listing.py

@@ -294,7 +294,10 @@ def _run_generation(sid, image_prompts):
                 output_path = os.path.join(s["dir"], f"{p['type']}_{sid}.png")
 
                 if is_openai:
-                    generate_image_openai(base_prompt, output_path, model, ref_img, quality, api_key=custom_image_key or custom_key)
+                    mask_mode = "auto"
+                    if ref_type == "scene":
+                        mask_mode = "invert"
+                    generate_image_openai(base_prompt, output_path, model, ref_img, quality, api_key=custom_image_key or custom_key, mask_mode=mask_mode)
                 else:
                     cf_label = cf_account.get("custom", False) and "CF custom" or f"CF #{cf_account_tried + 1}"
                     s["last_status"] = {"level": "info", "message": f"  → dùng {cf_label}", "time": time.time()}
@@ -339,7 +342,7 @@ def _run_generation(sid, image_prompts):
                         continue
                     try:
                         fb_path = os.path.join(s["dir"], f"{p['type']}_{sid}_fallback.png")
-                        generate_image_openai(base_prompt, fb_path, model, ref_img, quality, api_key=custom_image_key or custom_key)
+                        generate_image_openai(base_prompt, fb_path, model, ref_img, quality, api_key=custom_image_key or custom_key, mask_mode=mask_mode)
                         s["results"].append({
                             "type": p["type"], "label": p.get("label", p["type"]),
                             "prompt": base_prompt, "images": [fb_path], "status": "success",
@@ -481,7 +484,7 @@ async def edit_image(
             modified_prompt = f"{orig_prompt}\n\n{preserve}\n\nYêu cầu chỉnh sửa: {modification}"
             custom_key = s.get("api_key")
             custom_image_key = s.get("image_api_key")
-            generate_image_openai(modified_prompt, edit_path, model, product_ref, "low", api_key=custom_image_key or custom_key)
+            generate_image_openai(modified_prompt, edit_path, model, product_ref, "low", api_key=custom_image_key or custom_key, mask_mode="auto")
         else:
             modified_prompt = f"{orig_prompt}\n\n{preserve}\n\nYêu cầu chỉnh sửa: {modification}" if not ref_path else modification
             cf_account_id = s.get("cf_account_id") or None

backend/app/services/listing/generator.py

@@ -2,7 +2,21 @@ import base64
 import io
 import os
 import requests
-from PIL import Image
+from PIL import Image, ImageFilter
+
+
+def _make_mask(img, invert=False):
+    gray = img.convert("L")
+    threshold = 200
+    mask = gray.point(lambda p: 0 if p > threshold else 255)
+    if invert:
+        mask = mask.point(lambda p: 255 - p)
+    mask = mask.filter(ImageFilter.MaxFilter(7))
+    mask = mask.filter(ImageFilter.GaussianBlur(radius=3))
+    ext = mask.getextrema()
+    if ext == (255, 255) or ext == (0, 0):
+        return None
+    return mask.convert("L")
 
 
 CF_ACCOUNTS = [
@@ -116,7 +130,7 @@ def generate_image_flux(prompt, output_path, input_path=None, negative_prompt=No
     raise RuntimeError(f"Flux API error: {resp.status_code} {resp.text[:500]}")
 
 
-def generate_image_openai(prompt, output_path, model, input_path=None, quality="high", api_key=None):
+def generate_image_openai(prompt, output_path, model, input_path=None, quality="high", api_key=None, mask_mode="auto"):
     import requests as req
     from ...config import settings
     api_key = api_key or settings.OPENAI_IMAGE_API_KEY or settings.OPENAI_API_KEY
@@ -132,13 +146,24 @@ def generate_image_openai(prompt, output_path, model, input_path=None, quality="
     resp_json = None
     if input_path and os.path.exists(input_path):
         pil_img = Image.open(input_path).convert("RGBA")
-        buf = io.BytesIO()
-        pil_img.save(buf, format="PNG")
-        buf.seek(0)
+        img_buf = io.BytesIO()
+        pil_img.save(img_buf, format="PNG")
+        img_buf.seek(0)
+
+        files = {"image": ("input.png", img_buf, "image/png")}
+
+        if mask_mode != "none":
+            mask = _make_mask(pil_img, invert=(mask_mode == "invert"))
+            if mask is not None:
+                mask_buf = io.BytesIO()
+                mask.save(mask_buf, format="PNG")
+                mask_buf.seek(0)
+                files["mask"] = ("mask.png", mask_buf, "image/png")
+
         r = req.post(
             "https://api.openai.com/v1/images/edits",
             headers=headers,
-            files={"image": ("input.png", buf, "image/png")},
+            files=files,
             data=body,
             timeout=300,
         )
@@ -146,7 +171,7 @@ def generate_image_openai(prompt, output_path, model, input_path=None, quality="
             resp_json = r.json()
         else:
             err_msg = f"Edits endpoint failed: HTTP {r.status_code} {r.text[:500]}"
-            print(f"[generator] {err_msg}")  # log the actual error
+            print(f"[generator] {err_msg}")
             raise RuntimeError(err_msg)
 
     if resp_json is None: