init

agv_app/utils/qr_scanner.py

@@ -0,0 +1,99 @@
+"""
+二维码识别模块 - 使用 OpenCV 识别二维码获取 serialNumber
+"""
+import cv2
+import time
+import logging
+import numpy as np
+from typing import Optional, Tuple
+
+logger = logging.getLogger(__name__)
+
+# 尝试导入二维码识别库
+try:
+    from pyzbar.pyzbar import decode as qr_decode
+    PYZBAR_AVAILABLE = True
+except ImportError:
+    PYZBAR_AVAILABLE = False
+    logger.warning("pyzbar 未安装，尝试用 OpenCV 内置 QRCodeDetector")
+
+
+class QRScanner:
+    """二维码扫描器"""
+
+    def __init__(self, device_index: int = 0):
+        self.device_index = device_index
+        self._cap: Optional[cv2.VideoCapture] = None
+        self._qr_detector = cv2.QRCodeDetector()  # OpenCV 内置二维码检测器
+
+    def open(self) -> bool:
+        """打开摄像头"""
+        try:
+            # 强制 V4L2 后端，获取标准彩色格式（与 test/server.py 一致）
+            self._cap = cv2.VideoCapture(self.device_index, cv2.CAP_V4L2)
+            if self._cap.isOpened():
+                logger.info(f"摄像头 {self.device_index} 已打开 (V4L2)")
+                return True
+            else:
+                # fallback: 不指定后端
+                self._cap = cv2.VideoCapture(self.device_index)
+                if self._cap.isOpened():
+                    logger.info(f"摄像头 {self.device_index} 已打开 (默认后端)")
+                    return True
+                logger.error(f"无法打开摄像头 {self.device_index}")
+                return False
+        except Exception as e:
+            logger.error(f"摄像头打开失败: {e}")
+            return False
+
+    def close(self):
+        if self._cap:
+            self._cap.release()
+            self._cap = None
+
+    def read_frame(self) -> Optional[np.ndarray]:
+        """读取一帧"""
+        if not self._cap or not self._cap.isOpened():
+            return None
+        ret, frame = self._cap.read()
+        if not ret:
+            return None
+        return frame
+
+    def detect_qr(self, frame: np.ndarray) -> Optional[str]:
+        """从图像帧中检测二维码"""
+        if frame is None:
+            return None
+        try:
+            # OpenCV 内置二维码检测
+            data, vertices, _ = self._qr_detector.detectAndDecode(frame)
+            if data and len(data) > 0:
+                return data.strip()
+        except Exception as e:
+            logger.debug(f"二维码检测失败: {e}")
+        return None
+
+    def scan_once(self) -> Optional[str]:
+        """扫描一次（读取一帧并检测）"""
+        frame = self.read_frame()
+        return self.detect_qr(frame)
+
+    def scan_with_retry(self, max_attempts: int = 5, interval: float = 0.5) -> Optional[str]:
+        """多次扫描直到成功或达到最大次数"""
+        for i in range(max_attempts):
+            result = self.scan_once()
+            if result:
+                return result
+            time.sleep(interval)
+        return None
+
+    def get_preview_frame(self) -> Optional[np.ndarray]:
+        """获取预览帧（用于界面显示）"""
+        return self.read_frame()
+
+    def __enter__(self):
+        self.open()
+        return self
+
+    def __exit__(self, *args):
+        self.close()