修复信息窗反转和二维码窗口没全屏的 bug

face_rec.py

@@ -698,6 +698,8 @@ class FaceRecognitionSystem:
             x_pos = 0
             y_pos = 0
 
+            qr_height, qr_width = qr_image.shape[:2]
+
             rendered = self._build_qrcode_instruction_canvas(qr_image, (canvas_width, canvas_height))
             if rendered is None:
                 # 回退到原二维码展示
@@ -1907,14 +1909,14 @@ class FaceRecognitionSystem:
                             self.logger.debug("人脸消失,重置计时器")
                         self.face_present_start = None
 
+                # 镜像翻转：使画面与实际场景一致（在绘制信息之前）
+                frame = cv2.flip(frame, 1)
+
                 # 绘制信息
                 display_frame = self.draw_info_on_frame(frame)
 
                 # 使用缓存的屏幕尺寸拉伸视频帧到全屏
                 display_frame = cv2.resize(display_frame, (self.screen_width, self.screen_height), interpolation=cv2.INTER_LINEAR)
-                
-                # 镜像翻转：使画面与实际场景一致（取消默认的左右镜像）
-                display_frame = cv2.flip(display_frame, 1)
 
                 cv2.imshow(window_name, display_frame)