diff --git a/qurator/dinglehopper/cli.py b/qurator/dinglehopper/cli.py
index 32e159f..72d428d 100644
--- a/qurator/dinglehopper/cli.py
+++ b/qurator/dinglehopper/cli.py
@@ -84,6 +84,19 @@ def gen_diff_report(gt_in, ocr_in, css_prefix, joiner, none):
     )
 
 
+def json_float(value):
+    """Convert a float value to an JSON float.
+
+    This is here so that float('inf') yields "Infinity", not "inf".
+    """
+    if value == float("inf"):
+        return "Infinity"
+    elif value == float("-inf"):
+        return "-Infinity"
+    else:
+        return str(value)
+
+
 def process(gt, ocr, report_prefix, *, metrics=True, textequiv_level="region"):
     """Check OCR result against GT.
 
@@ -107,18 +120,6 @@ def process(gt, ocr, report_prefix, *, metrics=True, textequiv_level="region"):
         gt_words, ocr_words, css_prefix="w", joiner=" ", none="⋯"
     )
 
-    def json_float(value):
-        """Convert a float value to an JSON float.
-
-        This is here so that float('inf') yields "Infinity", not "inf".
-        """
-        if value == float("inf"):
-            return "Infinity"
-        elif value == float("-inf"):
-            return "-Infinity"
-        else:
-            return str(value)
-
     env = Environment(
         loader=FileSystemLoader(
             os.path.join(os.path.dirname(os.path.realpath(__file__)), "templates")
diff --git a/qurator/dinglehopper/cli_line_dirs.py b/qurator/dinglehopper/cli_line_dirs.py
index 48b86d2..4c07ce5 100644
--- a/qurator/dinglehopper/cli_line_dirs.py
+++ b/qurator/dinglehopper/cli_line_dirs.py
@@ -14,7 +14,7 @@ from .align import seq_align
 from .extracted_text import ExtractedText
 from .ocr_files import plain_extract
 from .config import Config
-from .cli import gen_diff_report
+from .cli import gen_diff_report, json_float
 
 
 def all_equal(iterable):
@@ -82,20 +82,6 @@ def process(gt_dir, ocr_dir, report_prefix, *, metrics=True):
             gt_words, ocr_words, css_prefix="l{0}-w".format(k), joiner=" ", none="⋯"
         )
 
-
-    # XXX this is a copy from cli.py
-    def json_float(value):
-        """Convert a float value to an JSON float.
-
-        This is here so that float('inf') yields "Infinity", not "inf".
-        """
-        if value == float("inf"):
-            return "Infinity"
-        elif value == float("-inf"):
-            return "-Infinity"
-        else:
-            return str(value)
-
     env = Environment(
         loader=FileSystemLoader(
             os.path.join(os.path.dirname(os.path.realpath(__file__)), "templates")