Merge missed text detection boxes in format lines

When merging provider and detection lines, some boxes may be missing,
but the layout check fails. This catches and merges in these boxes too.

Author: tarun-menta

marker/builders/line.py

@@ -211,7 +211,7 @@ def get_all_lines(self, document: Document, provider: PdfProvider):
 
                 # Add in the provider lines - merge ones that get broken by pdftext
                 merged_provider_lines = self.merge_provider_lines_detected_lines(
-                    provider_lines, detection_boxes, image_size, page_size
+                    provider_lines, detection_boxes, image_size, page_size, document_page.page_id
                 )
 
                 # If fixing lines, mark every line to be passed to the OCR model
@@ -391,6 +391,7 @@ def merge_provider_lines_detected_lines(
         text_lines: List[PolygonBox],
         image_size,
         page_size,
+        page_id,
     ):
         # When provider lines is empty or no lines detected, return provider lines
         if not provider_lines or not text_lines:
@@ -414,7 +415,7 @@ def merge_provider_lines_detected_lines(
         ]
 
         overlaps = matrix_intersection_area(provider_line_boxes, detected_line_boxes)
-
+        
         # Find potential merges
         merge_lines = defaultdict(list)
         for i in range(len(provider_line_boxes)):
@@ -532,4 +533,22 @@ def bbox_for_merge_section(
         # Sort to preserve original order
         out_provider_lines = sorted(out_provider_lines, key=lambda x: x[0])
         out_provider_lines = [p for _, p in out_provider_lines]
+
+        # Detected lines that do not overlap with any provider lines shoudl be outputted as-is
+        LineClass: Line = get_block_class(BlockTypes.Line)
+        for j in range(len(detected_line_boxes)):
+            if np.max(overlaps[:, j]) == 0:
+                detected_line_polygon = PolygonBox.from_bbox(detected_line_boxes[j])
+                out_provider_lines.append(
+                    ProviderOutput(
+                        line=LineClass(
+                            polygon=detected_line_polygon,
+                            page_id=page_id,
+                            text_extraction_method="surya",
+                        ),
+                        spans=[],
+                        chars=[],
+                    )
+                )
+
         return out_provider_lines