auto-save 2026-05-13 11:45 (~4)

api/main.py

@@ -68,10 +68,12 @@ class KeyElement(BaseModel):
     id: str             # uuid hex 8
     name_zh: str
     name_en: str = ""
-    position: str = ""  # 在画面中的位置描述（vision 给的）
-    source: Literal["auto", "manual", "region"] = "manual"  # auto=vision / manual=用户加 / region=画框
-    region: dict | None = None  # 用户画框的相对坐标 {x,y,w,h}（用于精准抠图）
-    cutout_id: str | None = None  # 已抠图 → /jobs/{id}/frames/{idx}/elements/{element_id}/cutout.png
+    position: str = ""
+    source: Literal["auto", "manual", "region"] = "manual"
+    region: dict | None = None
+    # 抠图（注：Gemini 输出 JPEG 不支持真透明，所以让模型在纯白 / 纯黑底上输出）
+    cutout_id: str | None = None  # 已抠图 → /jobs/{id}/frames/{idx}/elements/{element_id}/cutout.jpg
+    cutout_background: Literal["white", "black"] = "white"
     created_at: float = 0.0
 
 
@@ -1205,12 +1207,11 @@ def delete_element(job_id: str, idx: int, element_id: str) -> Job:
             removed = len(f.elements) < before
             # 若有抠图文件也删
             if removed:
-                cutout = job_dir(job_id) / "elements" / f"{idx:03d}_{element_id}.png"
-                if cutout.exists():
-                    try:
-                        cutout.unlink()
-                    except OSError:
-                        pass
+                for ext in ("jpg", "png"):
+                    cutout = job_dir(job_id) / "elements" / f"{idx:03d}_{element_id}.{ext}"
+                    if cutout.exists():
+                        try: cutout.unlink()
+                        except OSError: pass
         new_frames.append(f)
     if not removed:
         raise HTTPException(404, "element not found")
@@ -1218,10 +1219,14 @@ def delete_element(job_id: str, idx: int, element_id: str) -> Job:
     return job
 
 
+class CutoutReq(BaseModel):
+    background: Literal["white", "black"] = "white"
+
+
 @app.post("/jobs/{job_id}/frames/{idx}/elements/{element_id}/cutout", response_model=Job)
-def cutout_element(job_id: str, idx: int, element_id: str) -> Job:
-    """单元素抠图：调 nano-banana image edit 输出透明背景元素图"""
-    import time as _time
+def cutout_element(job_id: str, idx: int, element_id: str, req: CutoutReq | None = None) -> Job:
+    """单元素抠图：调 nano-banana image edit，输出纯白底 / 纯黑底元素图。
+    注：Gemini 输出 JPEG 不支持真 alpha，因此用纯色背景。"""
     job = JOBS.get(job_id)
     if not job:
         raise HTTPException(404, "job not found")
@@ -1238,18 +1243,21 @@ def cutout_element(job_id: str, idx: int, element_id: str) -> Job:
     if not src.exists():
         raise HTTPException(404, "source frame file missing")
 
+    background = (req.background if req else "white") or "white"
+    bg_phrase = f"pure {background}"
+
     target = (el.name_en or el.name_zh).strip()
     region_phrase = _region_to_phrase(el.region) if el.region else ""
     if region_phrase:
         prompt = (
             f"Extract whatever is in the {region_phrase} part of the image as a standalone asset. "
-            "Output on transparent background, isolated, no other objects."
+            f"Place it on a {bg_phrase} background, isolated, no other objects."
         )
     else:
         position_hint = f" Located in the {el.position} area." if el.position else ""
         prompt = (
             f"Extract the {target} from this image as a standalone asset.{position_hint} "
-            "Output on transparent background, isolated, no other objects."
+            f"Place it on a {bg_phrase} background, isolated, no other objects."
         )
     try:
         img_bytes, _mode = _image_edit_call(src, prompt, fallback_text=False, max_attempts=3)
@@ -1258,26 +1266,37 @@ def cutout_element(job_id: str, idx: int, element_id: str) -> Job:
 
     out_dir = job_dir(job_id) / "elements"
     out_dir.mkdir(parents=True, exist_ok=True)
-    out_path = out_dir / f"{idx:03d}_{element_id}.png"
+    # 实际是 JPEG bytes，文件用 .jpg 真名
+    out_path = out_dir / f"{idx:03d}_{element_id}.jpg"
     out_path.write_bytes(img_bytes)
+    # 旧版的 .png 文件（错命名为 .png 的 JPEG）也清理掉
+    old_png = out_dir / f"{idx:03d}_{element_id}.png"
+    if old_png.exists():
+        try: old_png.unlink()
+        except OSError: pass
 
     new_frames = []
     for f in job.frames:
         if f.index == idx:
             for e in f.elements:
                 if e.id == element_id:
-                    e.cutout_id = element_id  # marker that cutout exists; URL derived from id
+                    e.cutout_id = element_id
+                    e.cutout_background = background
         new_frames.append(f)
-    update(job, frames=new_frames, message=f"抠图完成 · {el.name_zh}")
+    update(job, frames=new_frames, message=f"抠图完成 · {el.name_zh}（{background} 底）")
     return job
 
 
-@app.get("/jobs/{job_id}/frames/{idx}/elements/{element_id}/cutout.png")
+@app.get("/jobs/{job_id}/frames/{idx}/elements/{element_id}/cutout.jpg")
 def get_cutout(job_id: str, idx: int, element_id: str):
-    p = job_dir(job_id) / "elements" / f"{idx:03d}_{element_id}.png"
+    p = job_dir(job_id) / "elements" / f"{idx:03d}_{element_id}.jpg"
     if not p.exists():
+        # 兼容老数据
+        legacy = job_dir(job_id) / "elements" / f"{idx:03d}_{element_id}.png"
+        if legacy.exists():
+            return FileResponse(legacy, media_type="image/jpeg")
         raise HTTPException(404, "cutout not found")
-    return FileResponse(p, media_type="image/png")
+    return FileResponse(p, media_type="image/jpeg")
 
 
 # ---------- 删除：关键帧 / 单张生成图 ----------
@@ -1305,9 +1324,10 @@ def delete_frame(job_id: str, idx: int) -> Job:
     # 该帧的所有元素抠图（命名前缀 {idx:03d}_）
     elements_dir = d / "elements"
     if elements_dir.exists():
-        for p in elements_dir.glob(f"{idx:03d}_*.png"):
-            try: p.unlink()
-            except OSError: pass
+        for ext in ("png", "jpg"):
+            for p in elements_dir.glob(f"{idx:03d}_*.{ext}"):
+                try: p.unlink()
+                except OSError: pass
     # 该帧的所有生成图
     gen_dir = d / "gen"
     if gen_dir.exists():