小bug修改

preview.py

@@ -283,6 +283,7 @@ class PreviewWindow:
                             photo = ImageTk.PhotoImage(image=pil_image)
                             # 保持引用，避免被GC
                             self.photo_objects[idx] = photo
+                            self._grid_photos.append(photo)
                             
                             images_to_draw.append((photo, center_x, center_y))
                             texts_to_draw.append((center_x, y + 15, name, 'white'))
@@ -416,6 +417,8 @@ class PreviewWindow:
         canvas.pack(fill=tk.BOTH, expand=True)
         
         photo_obj = {}
+        # 持久引用大窗当前帧 PhotoImage，避免GC
+        self._large_photos = []
         
         def update_large_once():
             if not self.running or not self.large_window.winfo_exists():
@@ -441,8 +444,9 @@ class PreviewWindow:
                         resized_frame = cv2.cvtColor(resized_frame, cv2.COLOR_BGR2RGB)
                     pil_image = Image.fromarray(resized_frame)
                     photo = ImageTk.PhotoImage(image=pil_image)
-                    # 保存引用到字典，确保不被GC
+                    # 保存引用到字典和列表，确保不被GC
                     photo_obj['img'] = photo
+                    self._large_photos = [photo]
 
                     # 清空并绘制新图像
                     canvas.delete("all")