diff --git a/src/calibre/ebooks/html/input.py b/src/calibre/ebooks/html/input.py
index 51c74228b7..d57bfddd3e 100644
--- a/src/calibre/ebooks/html/input.py
+++ b/src/calibre/ebooks/html/input.py
@@ -491,6 +491,9 @@ class HTMLInput(InputFormatPlugin):
         return (None, raw)
 
 	def preprocess_html(self, html):
+        if not hasattr(self, 'log'):
+            from calibre.utils.logging import default_log
+            self.log = default_log
 		self.log("*********  Preprocessing HTML  *********")
 		# Detect Chapters to match the xpath in the GUI
 		chapdetect = re.compile(r'(?=</?(br|p|span))(</?(br|p|span)[^>]*>)?\s*(?P<chap>(<(i|b)><(i|b)>|<(i|b)>)?(.?Chapter|Epilogue|Prologue|Book|Part|Dedication)\s*([\d\w-]+(\s\w+)?)?(</(i|b)></(i|b)>|</(i|b)>)?)(</?(p|br|span)[^>]*>)', re.IGNORECASE)