feat(新增水印去除功能): 在MinerU预处理器中添加水印去除功能，优化图像处理流程

ocr_tools/universal_doc_parser/models/adapters/mineru_adapter.py

@@ -18,6 +18,7 @@ if str(ocr_platform_root) not in sys.path:
 
 from .base import BasePreprocessor, BaseLayoutDetector, BaseVLRecognizer, BaseOCRRecognizer
 from ocr_utils.coordinate_utils import CoordinateUtils
+from ocr_utils.watermark_utils import remove_watermark_from_image_rgb
 
 # 导入MinerU组件
 try:
@@ -65,11 +66,28 @@ class MinerUPreprocessor(BasePreprocessor):
 
         rotate_angle = 0
         processed_image = image
-        
+
+        # 水印去除（在方向校正之前，避免旋转引入额外噪声）
+        watermark_cfg = self.config.get('watermark_removal', {})
+        if watermark_cfg.get('enabled', False):
+            threshold = watermark_cfg.get('threshold', 160)
+            morph_close_kernel = watermark_cfg.get('morph_close_kernel', 0)
+            try:
+                processed_image = remove_watermark_from_image_rgb(
+                    processed_image,
+                    threshold=threshold,
+                    morph_close_kernel=morph_close_kernel,
+                    return_pil=False,
+                )
+                logger.info(f"🧹 Watermark removed (threshold={threshold})")
+            except Exception as e:
+                logger.warning(f"⚠️ Watermark removal failed, using original: {e}")
+                processed_image = image
+
         # 方向校正
         if self.orientation_classifier is not None:
             try:
-                rotate_angle = int(self.orientation_classifier.predict(image))
+                rotate_angle = int(self.orientation_classifier.predict(processed_image))
                 processed_image = self._apply_rotation(processed_image, rotate_angle)
                 logger.info(f"📐 Applied rotation: {rotate_angle}")
             except Exception as e: