feat(park-desktop): admin 后台新 UI + vision_yolo 手势接入（merge 自旧仓库 4e73a6b）

backend/app/vision_yolo.py

@@ -19,8 +19,12 @@ from pathlib import Path
 
 from PIL import Image
 
+from .config import settings
+
 log = logging.getLogger("dpm.vision")
 
+_frame_seq = 0
+
 MODEL_DIR = Path(__file__).resolve().parent.parent / "models"
 FACE_MODEL_PATH = MODEL_DIR / "yolov8n-face.pt"
 POSE_MODEL_PATH = MODEL_DIR / "yolov8n-pose.pt"
@@ -188,6 +192,40 @@ def predict_jpeg(jpeg_bytes: bytes):
     }
 
 
+def _should_save(data: dict) -> bool:
+    """仅当画面检测到人脸/手势时才值得落盘保存。"""
+    return (
+        int(data.get("faces") or 0) > 0
+        or bool(data.get("raised"))
+        or bool(data.get("fists"))
+        or bool(data.get("both_up"))
+        or bool(data.get("pointing"))
+        or bool(data.get("hands_close"))
+    )
+
+
+def maybe_save_frame(jpeg: bytes, data: dict):
+    """仅将命中（有人/有动作）的 JPEG 帧落盘到 MEDIA_DIR/video/<小时目录>/，便于排查识别链路。
+       目录按小时分割（YYYYMMDD_HH），不自动清理。
+       可通过 DPM_SAVE_VISION_FRAMES=0 关闭，或 DPM_VISION_SAVE_DIR 改目录。"""
+    global _frame_seq
+    if not settings.SAVE_VISION_FRAMES:
+        return
+    if not _should_save(data):
+        return
+    _frame_seq += 1
+    ts = time.strftime("%Y%m%d_%H%M%S")
+    hour = time.strftime("%Y%m%d_%H")
+    try:
+        save_dir = settings.VISION_FRAME_SAVE_DIR / hour
+        save_dir.mkdir(parents=True, exist_ok=True)
+        path = save_dir / f"{ts}_{_frame_seq:05d}.jpg"
+        with open(path, "wb") as f:
+            f.write(jpeg)
+    except Exception as e:  # noqa: BLE001
+        log.warning("vision: 保存帧失败 %s", e)
+
+
 def predict_base64(b64: str):
     """入口：base64 JPEG → 检测结果 dict（含 ok 标记，失败时带 error）"""
     try:
@@ -198,6 +236,7 @@ def predict_base64(b64: str):
     try:
         data = predict_jpeg(jpeg)
         data["ok"] = True
+        maybe_save_frame(jpeg, data)
         return data
     except Exception as e:  # noqa: BLE001
         log.error("vision: 推理失败 %s", e, exc_info=True)