Camera zoom

emotion.py

@@ -18,6 +18,7 @@ EMA_ALPHA = 0.45
 CONF_TH = 40.0
 SWITCH_CONFIRM_SEC = 2.5
 IOU_TH = 0.25
+ZOOM_FACTOR = 1.5
 
 DETECTOR_BACKEND = "mtcnn"     # 想快一點可改 "opencv"
 ALIGN_FACE = True
@@ -177,6 +178,28 @@ def _downsample_rgb(frame: np.ndarray, target_w: int) -> np.ndarray:
     img = img.resize((target_w, new_h))
     return np.array(img)
 
+def _zoom_center(frame: np.ndarray, zoom: float) -> np.ndarray:
+    """
+    裁切畫面中心以模擬數位變焦。
+    zoom: 放大倍率 (例如 1.5)
+    """
+    if frame is None or zoom <= 1.0:
+        return frame
+        
+    h, w = frame.shape[:2]
+    
+    # 計算新的寬高
+    new_w = int(w / zoom)
+    new_h = int(h / zoom)
+    
+    # 計算起始點 (讓裁切框置中)
+    start_x = (w - new_w) // 2
+    start_y = (h - new_h) // 2
+    
+    # 進行裁切
+    cropped = frame[start_y : start_y + new_h, start_x : start_x + new_w]
+    return cropped
+
 
 def _iou(a: Tuple[int, int, int, int], b: Tuple[int, int, int, int]) -> float:
     ax, ay, aw, ah = a
@@ -279,6 +302,8 @@ def on_stream(frame_rgb: np.ndarray, st: AppState):
             st,
             gr.update(value="重新攝影機辨識"),
         )
+    
+    frame_rgb = _zoom_center(frame_rgb, ZOOM_FACTOR)
 
     now = time.time()
     if now - st.last_analyze_t < ANALYZE_EVERY_SEC: