feat: add area_center function and enhance OCR processing for white letters

module/base/utils/utils.py

@@ -274,6 +274,20 @@ def area_size(area):
     )
 
 
+def area_center(area):
+    """
+    Get the center of an area
+
+    Args:
+        area: (upper_left_x, upper_left_y, bottom_right_x, bottom_right_y)
+
+    Returns:
+        tuple: (x, y)
+    """
+    x1, y1, x2, y2 = area
+    return (x1 + x2) / 2, (y1 + y2) / 2
+
+
 def point_limit(point, area):
     """
     Limit point in an area.

module/ocr/ocr.py

@@ -3,13 +3,14 @@ import time
 from datetime import timedelta
 from typing import Optional
 
+import cv2
 import numpy as np
 from pponnxcr.predict_system import BoxedResult
 
 import module.config.server as server
 from module.base.button import ButtonWrapper
 from module.base.decorator import cached_property
-from module.base.utils import area_pad, corner2area, crop, float2str
+from module.base.utils import area_pad, corner2area, crop, extract_white_letters, float2str
 from module.exception import ScriptError
 from module.logger import logger
 from module.ocr.keyword import Keyword
@@ -416,3 +417,20 @@ class Duration(Ocr):
         if number is None:
             return 0
         return int(number)
+
+
+class OcrWhiteLetterOnComplexBackground(Ocr):
+    def pre_process(self, image):
+        image = extract_white_letters(image, threshold=255)
+        image = cv2.merge([image, image, image])
+        return image
+
+    def detect_and_ocr(self, *args, **kwargs):
+        # Try hard to lower TextSystem.box_thresh
+        backup = self.model.text_detector.box_thresh
+        self.model.text_detector.box_thresh = 0.2
+
+        result = super().detect_and_ocr(*args, **kwargs)
+
+        self.model.text_detector.box_thresh = backup
+        return result