feat: add options for choosing OCR engines (#118)

---------

Signed-off-by: Michele Dolfi <dol@zurich.ibm.com>
Signed-off-by: Nikos Livathinos <nli@zurich.ibm.com>
Signed-off-by: Peter Staar <taa@zurich.ibm.com>
Co-authored-by: Nikos Livathinos <nli@zurich.ibm.com>
Co-authored-by: Peter Staar <taa@zurich.ibm.com>

docling/models/easyocr_model.py

@@ -4,21 +4,33 @@ from typing import Iterable
 import numpy
 
 from docling.datamodel.base_models import BoundingBox, CoordOrigin, OcrCell, Page
+from docling.datamodel.pipeline_options import EasyOcrOptions
 from docling.models.base_ocr_model import BaseOcrModel
 
 _log = logging.getLogger(__name__)
 
 
 class EasyOcrModel(BaseOcrModel):
-    def __init__(self, config):
-        super().__init__(config)
+    def __init__(self, enabled: bool, options: EasyOcrOptions):
+        super().__init__(enabled=enabled, options=options)
+        self.options: EasyOcrOptions
 
         self.scale = 3  # multiplier for 72 dpi == 216 dpi.
 
         if self.enabled:
-            import easyocr
+            try:
+                import easyocr
+            except ImportError:
+                raise ImportError(
+                    "EasyOCR is not installed. Please install it via `pip install easyocr` to use this OCR engine. "
+                    "Alternatively, Docling has support for other OCR engines. See the documentation."
+                )
 
-            self.reader = easyocr.Reader(config["lang"])
+            self.reader = easyocr.Reader(
+                lang_list=self.options.lang,
+                model_storage_directory=self.options.model_storage_directory,
+                download_enabled=self.options.download_enabled,
+            )
 
     def __call__(self, page_batch: Iterable[Page]) -> Iterable[Page]:
 
@@ -31,6 +43,9 @@ class EasyOcrModel(BaseOcrModel):
 
             all_ocr_cells = []
             for ocr_rect in ocr_rects:
+                # Skip zero area boxes
+                if ocr_rect.area() == 0:
+                    continue
                 high_res_image = page._backend.get_page_image(
                     scale=self.scale, cropbox=ocr_rect
                 )