Sync to ldolse heuristics branch.

src/calibre/ebooks/conversion/plumber.py

@@ -523,7 +523,7 @@ OptionRecommendation(name='delete_blank_paragraphs',
     
 OptionRecommendation(name='format_scene_breaks',
     recommended_value=False, level=OptionRecommendation.LOW,
-    help=_('Detects left aligned scene break markers and center aligns them. '
+    help=_('left aligned scene break markers are center aligned. '
            'Replace soft scene breaks that use multiple blank lines with'
            'horizontal rules.')),
 

src/calibre/ebooks/conversion/utils.py

@@ -18,6 +18,14 @@ class PreProcessor(object):
         self.html_preprocess_sections = 0
         self.found_indents = 0
         self.extra_opts = extra_opts
+        self.deleted_nbsps = False
+        self.totalwords = 0
+        self.min_chapters = 1
+        self.chapters_no_title = 0
+        self.chapters_with_title = 0
+        self.linereg = re.compile('(?<=<p).*?(?=</p>)', re.IGNORECASE|re.DOTALL)
+        self.blankreg = re.compile(r'\s*(?P<openline><p(?!\sid=\"softbreak\")[^>]*>)\s*(?P<closeline></p>)', re.IGNORECASE)
+        self.multi_blank = re.compile(r'(\s*<p[^>]*>\s*</p>){2,}', re.IGNORECASE)
 
     def is_pdftohtml(self, src):
         return '<!-- created by calibre\'s pdftohtml -->' in src[:1000]
@@ -44,6 +52,14 @@ class PreProcessor(object):
                 " section markers based on punctuation. - " + unicode(chap))
         return '<'+styles+' style="page-break-before:always">'+chap
 
+    def analyze_title_matches(self, match):
+        chap = match.group('chap')
+        title = match.group('title')
+        if not title:
+            self.chapters_no_title = self.chapters_no_title + 1
+        else:
+            self.chapters_with_title = self.chapters_with_title + 1
+
     def insert_indent(self, match):
         pstyle = match.group('formatting')
         span = match.group('span')
@@ -120,7 +136,6 @@ class PreProcessor(object):
         '''
         # Typical chapters are between 2000 and 7000 words, use the larger number to decide the
         # minimum of chapters to search for
-        self.min_chapters = 1
         if wordcount > 7000:
             self.min_chapters = int(ceil(wordcount / 7000.))
         #print "minimum chapters required are: "+str(self.min_chapters)
@@ -159,29 +174,42 @@ class PreProcessor(object):
         default_title = r"(<[ibu][^>]*>)?\s{0,3}([\w\'’\"-]+\s{0,3}){1,5}?(</[ibu][^>]*>)?(?=<)"
 
         chapter_types = [
-            [r"[^'\"]?(Introduction|Synopsis|Acknowledgements|Chapter|Kapitel|Epilogue|Volume\s|Prologue|Book\s|Part\s|Dedication|Preface)\s*([\d\w-]+\:?\'?\s*){0,5}", True, "Searching for common Chapter Headings"],
-            [r"<b[^>]*>\s*(<span[^>]*>)?\s*(?!([*#•]+\s*)+)(\s*(?=[\d.\w#\-*\s]+<)([\d.\w#-*]+\s*){1,5}\s*)(?!\.)(</span>)?\s*</b>", True, "Searching for emphasized lines"], # Emphasized lines
-            [r"[^'\"]?(\d+(\.|:)|CHAPTER)\s*([\dA-Z\-\'\"#,]+\s*){0,7}\s*", True, "Searching for numeric chapter headings"],  # Numeric Chapters
-            [r"([A-Z]\s+){3,}\s*([\d\w-]+\s*){0,3}\s*", True, "Searching for letter spaced headings"],  # Spaced Lettering
-            [r"[^'\"]?(\d+\.?\s+([\d\w-]+\:?\'?-?\s?){0,5})\s*", True, "Searching for numeric chapters with titles"], # Numeric Titles
-            [r"[^'\"]?(\d+|CHAPTER)\s*([\dA-Z\-\'\"\?!#,]+\s*){0,7}\s*", True, "Searching for simple numeric chapter headings"],  # Numeric Chapters, no dot or colon
-            [r"\s*[^'\"]?([A-Z#]+(\s|-){0,3}){1,5}\s*", False, "Searching for chapters with Uppercase Characters" ] # Uppercase Chapters
+            [r"[^'\"]?(CHAPTER|Kapitel)\s*([\dA-Z\-\'\"\?!#,]+\s*){0,7}\s*", True, "Searching for most common chapter headings", 'chapter'],  # Highest frequency headings which include titles
+            [r"[^'\"]?(Introduction|Synopsis|Acknowledgements|Epilogue|Volume\s|Prologue|Book\s|Part\s|Dedication|Preface)\s*([\d\w-]+\:?\'?\s*){0,5}", True, "Searching for common section headings", 'common'],
+            [r"<b[^>]*>\s*(<span[^>]*>)?\s*(?!([*#•=]+\s*)+)(\s*(?=[\d.\w#\-*\s]+<)([\d.\w#-*]+\s*){1,5}\s*)(?!\.)(</span>)?\s*</b>", True, "Searching for emphasized lines", 'emphasized'], # Emphasized lines
+            [r"[^'\"]?(\d+(\.|:))\s*([\dA-Z\-\'\"#,]+\s*){0,7}\s*", True, "Searching for numeric chapter headings", 'numeric'],  # Numeric Chapters
+            [r"([A-Z]\s+){3,}\s*([\d\w-]+\s*){0,3}\s*", True, "Searching for letter spaced headings", 'letter_spaced'],  # Spaced Lettering
+            [r"[^'\"]?(\d+\.?\s+([\d\w-]+\:?\'?-?\s?){0,5})\s*", True, "Searching for numeric chapters with titles", 'numeric_title'], # Numeric Titles
+            [r"[^'\"]?(\d+)\s*([\dA-Z\-\'\"\?!#,]+\s*){0,7}\s*", True, "Searching for simple numeric headings", 'plain_number'],  # Numeric Chapters, no dot or colon
+            [r"\s*[^'\"]?([A-Z#]+(\s|-){0,3}){1,5}\s*", False, "Searching for chapters with Uppercase Characters", 'uppercase' ] # Uppercase Chapters
             ]
 
-        # Start with most typical chapter headings, get more aggressive until one works
-        for [chapter_type, lookahead_ignorecase, log_message] in chapter_types:
-            if self.html_preprocess_sections >= self.min_chapters:
-                break
-            full_chapter_line = chapter_line_open+chapter_header_open+chapter_type+chapter_header_close+chapter_line_close
-            n_lookahead = re.sub("(ou|in|cha)", "lookahead_", full_chapter_line)
-            self.log("Marked " + unicode(self.html_preprocess_sections) + " headings, " + log_message)
-            if lookahead_ignorecase:
-                chapter_marker = init_lookahead+full_chapter_line+blank_lines+n_lookahead_open+n_lookahead+n_lookahead_close+opt_title_open+title_line_open+title_header_open+default_title+title_header_close+title_line_close+opt_title_close
-                chapdetect = re.compile(r'%s' % chapter_marker, re.IGNORECASE)
-            else:
-                chapter_marker = init_lookahead+full_chapter_line+blank_lines+opt_title_open+title_line_open+title_header_open+default_title+title_header_close+title_line_close+opt_title_close+n_lookahead_open+n_lookahead+n_lookahead_close
-                chapdetect = re.compile(r'%s' % chapter_marker, re.UNICODE)
-            html = chapdetect.sub(self.chapter_head, html)
+        def recurse_patterns(html, analyze):
+            # Start with most typical chapter headings, get more aggressive until one works
+            for [chapter_type, lookahead_ignorecase, log_message, type_name] in chapter_types:
+                if self.html_preprocess_sections >= self.min_chapters:
+                    break
+                full_chapter_line = chapter_line_open+chapter_header_open+chapter_type+chapter_header_close+chapter_line_close
+                n_lookahead = re.sub("(ou|in|cha)", "lookahead_", full_chapter_line)
+                self.log("Marked " + unicode(self.html_preprocess_sections) + " headings, " + log_message)
+                if lookahead_ignorecase:
+                    chapter_marker = init_lookahead+full_chapter_line+blank_lines+n_lookahead_open+n_lookahead+n_lookahead_close+opt_title_open+title_line_open+title_header_open+default_title+title_header_close+title_line_close+opt_title_close
+                    chapdetect = re.compile(r'%s' % chapter_marker, re.IGNORECASE)
+                else:
+                    chapter_marker = init_lookahead+full_chapter_line+blank_lines+opt_title_open+title_line_open+title_header_open+default_title+title_header_close+title_line_close+opt_title_close+n_lookahead_open+n_lookahead+n_lookahead_close
+                    chapdetect = re.compile(r'%s' % chapter_marker, re.UNICODE)
+                if analyze:
+                    hits = len(chapdetect.findall(html))
+                    print unicode(type_name)+" had "+unicode(hits)+" hits"
+                    chapdetect.sub(self.analyze_title_matches, html)
+                    print unicode(self.chapters_no_title)+" chapters with no title"
+                    print unicode(self.chapters_with_title)+" chapters with titles"
+                else:
+                    html = chapdetect.sub(self.chapter_head, html)
+                    return html
+
+        recurse_patterns(html, True)
+        html = recurse_patterns(html, False)
 
         words_per_chptr = wordcount
         if words_per_chptr > 0 and self.html_preprocess_sections > 0:
@@ -192,35 +220,48 @@ class PreProcessor(object):
     def punctuation_unwrap(self, length, content, format):
         '''
         Unwraps lines based on line length and punctuation
-        supports range of potential html markup and text files
+        supports a range of html markup and text files
         '''
         # define the pieces of the regex
         lookahead = "(?<=.{"+str(length)+"}([a-zäëïöüàèìòùáćéíóńśúâêîôûçąężıãõñæøþðß,:)\IA\u00DF]|(?<!\&\w{4});))" # (?<!\&\w{4});) is a semicolon not part of an entity
-        line_ending = "\s*</(span|p|div)>\s*(</(p|span|div)>)?"
+        em_en_lookahead = "(?<=.{"+str(length)+"}[\u2013\u2014])"
+        soft_hyphen = "\xad"
+        line_ending = "\s*</(span|[iubp]|div)>\s*(</(span|[iubp]|div)>)?"
         blanklines = "\s*(?P<up2threeblanks><(p|span|div)[^>]*>\s*(<(p|span|div)[^>]*>\s*</(span|p|div)>\s*)</(span|p|div)>\s*){0,3}\s*"
-        line_opening = "<(span|div|p)[^>]*>\s*(<(span|div|p)[^>]*>)?\s*"
+        line_opening = "<(span|[iubp]|div)[^>]*>\s*(<(span|[iubp]|div)[^>]*>)?\s*"
         txt_line_wrap = u"((\u0020|\u0009)*\n){1,4}"
 
         unwrap_regex = lookahead+line_ending+blanklines+line_opening
+        em_en_unwrap_regex = em_en_lookahead+line_ending+blanklines+line_opening
+        shy_unwrap_regex = soft_hyphen+line_ending+blanklines+line_opening
+
         if format == 'txt':
             unwrap_regex = lookahead+txt_line_wrap
+            em_en_unwrap_regex = em_en_lookahead+txt_line_wrap
+            shy_unwrap_regex = soft_hyphen+txt_line_wrap
 
         unwrap = re.compile(u"%s" % unwrap_regex, re.UNICODE)
+        em_en_unwrap = re.compile(u"%s" % em_en_unwrap_regex, re.UNICODE)
+
         content = unwrap.sub(' ', content)
+        content = em_en_unwrap.sub('', content)
         return content
 
+    def txt_process(self, match):
+        from calibre.ebooks.txt.processor import convert_basic, preserve_spaces, \
+        separate_paragraphs_single_line
+        content = match.group('text')
+        content = separate_paragraphs_single_line(content)
+        content = preserve_spaces(content)
+        content = convert_basic(content, epub_split_size_kb=0)
+        return content
 
-    def text_process_pre(self, html):
+    def markup_pre(self, html):
         pre = re.compile(r'<pre>', re.IGNORECASE)
-        if len(pre.findall(html)) == 1:
+        if len(pre.findall(html)) >= 1:
             self.log("Running Text Processing")
-            from calibre.ebooks.txt.processor import convert_basic, preserve_spaces, \
-            separate_paragraphs_single_line
             outerhtml = re.compile(r'.*?(?<=<pre>)(?P<text>.*)(?=</pre>).*', re.IGNORECASE|re.DOTALL)
-            html = outerhtml.sub('\g<text>', html)
-            html = separate_paragraphs_single_line(html)
-            html = preserve_spaces(html)
-            html = convert_basic(html, epub_split_size_kb=0)
+            html = outerhtml.sub(self.txt_process, html)
         else:
             # Add markup naively
             # TODO - find out if there are cases where there are more than one <pre> tag or
@@ -253,142 +294,153 @@ class PreProcessor(object):
         html = re.sub(r"\s*<span[^>]*>\s*(<span[^>]*>\s*</span>){0,2}\s*</span>\s*", " ", html)
         html = re.sub(r"\s*<[ibu][^>]*>\s*(<[ibu][^>]*>\s*</[ibu]>\s*){0,2}\s*</[ibu]>", " ", html)
         html = re.sub(r"\s*<span[^>]*>\s*(<span[^>]>\s*</span>){0,2}\s*</span>\s*", " ", html)
+        self.deleted_nbsps = True
         return html
 
+    def analyze_line_endings(self, html):
+        '''
+        determines the type of html line ending used most commonly in a document
+        use before calling docanalysis functions
+        '''
+        paras_reg = re.compile('<p[^>]*>', re.IGNORECASE)
+        spans_reg = re.compile('<span[^>]*>', re.IGNORECASE)
+        paras = len(paras_reg.findall(html))
+        spans = len(spans_reg.findall(html))
+        if spans > 1:
+            if float(paras) / float(spans) < 0.75:
+                return 'spanned_html'
+            else:
+                return 'html'
+        else:
+            return 'html'
+
+    def analyze_blanks(self, html):
+        blanklines = self.blankreg.findall(html)
+        lines = self.linereg.findall(html)
+        if len(lines) > 1:
+            self.log("There are " + unicode(len(blanklines)) + " blank lines. " +
+                    unicode(float(len(blanklines)) / float(len(lines))) + " percent blank")
+                    
+            if float(len(blanklines)) / float(len(lines)) > 0.40:
+                return True
+            else:
+                return False
+
+    def cleanup_required(self):
+        for option in ['unwrap_lines', 'markup_chapter_headings', 'format_scene_breaks', 'delete_blank_paragraphs']:
+            if getattr(self.extra_opts, option, False):
+                return True
+        return False
+
 
     def __call__(self, html):
         self.log("*********  Preprocessing HTML  *********")
 
         # Count the words in the document to estimate how many chapters to look for and whether
         # other types of processing are attempted
-        totalwords = 0
-        totalwords = self.get_word_count(html)
+        try:
+            self.totalwords = self.get_word_count(html)
+        except:
+            self.log("Can't get wordcount")
 
-        if totalwords < 50:
+        if 0 < self.totalwords < 50:
             self.log("flow is too short, not running heuristics")
             return html
 
         # Arrange line feeds and </p> tags so the line_length and no_markup functions work correctly
         html = self.arrange_htm_line_endings(html)
 
-
         ###### Check Markup ######
         #
         # some lit files don't have any <p> tags or equivalent (generally just plain text between
         # <pre> tags), check and  mark up line endings if required before proceeding
         if self.no_markup(html, 0.1):
             self.log("not enough paragraph markers, adding now")
-            # check if content is in pre tags, use txt processor to mark up if so
-            html = self.text_process_pre(html)
+            # markup using text processing
+            html = self.markup_pre(html)
 
-        ###### Mark Indents/Cleanup ######
-        #
         # Replace series of non-breaking spaces with text-indent
-        html = self.fix_nbsp_indents(html)
-        
-        html = self.cleanup_markup(html)
+        if getattr(self.extra_opts, 'fix_indents', True):
+            html = self.fix_nbsp_indents(html)
+
+        if self.cleanup_required():
+            html = self.cleanup_markup(html)
 
         # ADE doesn't render <br />, change to empty paragraphs
         #html = re.sub('<br[^>]*>', u'<p>\u00a0</p>', html)
 
-        # If more than 40% of the lines are empty paragraphs and the user has enabled delete
-        # blank paragraphs then delete blank lines to clean up spacing
-        linereg = re.compile('(?<=<p).*?(?=</p>)', re.IGNORECASE|re.DOTALL)
-        blankreg = re.compile(r'\s*(?P<openline><p(?!\sid=\"softbreak\")[^>]*>)\s*(?P<closeline></p>)', re.IGNORECASE)
-        multi_blank = re.compile(r'(\s*<p[^>]*>\s*</p>){2,}', re.IGNORECASE)
-        blanklines = blankreg.findall(html)
-        lines = linereg.findall(html)
-        blanks_between_paragraphs = False
-        print "delete blank paragraphs is "+str(getattr(self.extra_opts, 'delete_blank_paragraphs', False))
-        if len(lines) > 1:
-            self.log("There are " + unicode(len(blanklines)) + " blank lines. " +
-                    unicode(float(len(blanklines)) / float(len(lines))) + " percent blank")
-                    
-            if float(len(blanklines)) / float(len(lines)) > 0.40:
-                blanks_between_paragraphs = True
-                print "blanks between paragraphs is marked True"
-            else:
-                blanks_between_paragraphs = False
+        # Determine whether the document uses interleaved blank lines
+        blanks_between_paragraphs = self.analyze_blanks(html)
 
         #self.dump(html, 'before_chapter_markup')
         # detect chapters/sections to match xpath or splitting logic
-        #
 
-        html = self.markup_chapters(html, totalwords, blanks_between_paragraphs)
+        if getattr(self.extra_opts, 'markup_chapter_headings', True):
+            html = self.markup_chapters(html, self.totalwords, blanks_between_paragraphs)
 
+        # If more than 40% of the lines are empty paragraphs and the user has enabled delete
+        # blank paragraphs then delete blank lines to clean up spacing
         if blanks_between_paragraphs and getattr(self.extra_opts,
         'delete_blank_paragraphs', False):
             self.log("deleting blank lines")
-            html = multi_blank.sub('\n<p id="softbreak" style="margin-top:1.5em; margin-bottom:1.5em"> </p>', html)
-            html = blankreg.sub('', html)
+            html = self.multi_blank.sub('\n<p id="softbreak" style="margin-top:1.5em; margin-bottom:1.5em"> </p>', html)
+            html = self.blankreg.sub('', html)
             
         ###### Unwrap lines ######
-        #
-        # Some OCR sourced files have line breaks in the html using a combination of span & p tags
-        # span are used for hard line breaks, p for new paragraphs.  Determine which is used so
-        # that lines can be un-wrapped across page boundaries
-        paras_reg = re.compile('<p[^>]*>', re.IGNORECASE)
-        spans_reg = re.compile('<span[^>]*>', re.IGNORECASE)
-        paras = len(paras_reg.findall(html))
-        spans = len(spans_reg.findall(html))
-        if spans > 1:
-            if float(paras) / float(spans) < 0.75:
-                format = 'spanned_html'
-            else:
-                format = 'html'
-        else:
-            format = 'html'
-        # Check Line histogram to determine if the document uses hard line breaks, If 50% or
-        # more of the lines break in the same region of the document then unwrapping is required
-        docanalysis = DocAnalysis(format, html)
-        hardbreaks = docanalysis.line_histogram(.50)
-        self.log("Hard line breaks check returned "+unicode(hardbreaks))
-        # Calculate Length
-        unwrap_factor = getattr(self.extra_opts, 'html_unwrap_factor', 0.4)
-        length = docanalysis.line_length(unwrap_factor)
-        self.log("Median line length is " + unicode(length) + ", calculated with " + format + " format")
-        # only go through unwrapping code if the histogram shows unwrapping is required or if the user decreased the default unwrap_factor
-        if hardbreaks or unwrap_factor < 0.4:
-            self.log("Unwrapping required, unwrapping Lines")
-            # Unwrap em/en dashes
-            html = re.sub(u'(?<=.{%i}[\u2013\u2014])\s*(?=<)(</span>\s*(</[iubp]>\s*<[iubp][^>]*>\s*)?<span[^>]*>|</[iubp]>\s*<[iubp][^>]*>)?\s*(?=[[a-z\d])' % length, '', html)
-            # Dehyphenate
-            self.log("Unwrapping/Removing hyphens")
-            dehyphenator = Dehyphenator()
-            html = dehyphenator(html,'html', length)
-            self.log("Done dehyphenating")
-            # Unwrap lines using punctation and line length
-            #unwrap_quotes = re.compile(u"(?<=.{%i}\"')\s*</(span|p|div)>\s*(</(p|span|div)>)?\s*(?P<up2threeblanks><(p|span|div)[^>]*>\s*(<(p|span|div)[^>]*>\s*</(span|p|div)>\s*)</(span|p|div)>\s*){0,3}\s*<(span|div|p)[^>]*>\s*(<(span|div|p)[^>]*>)?\s*(?=[a-z])" % length, re.UNICODE)
-            html = self.punctuation_unwrap(length, html, 'html')
-            #check any remaining hyphens, but only unwrap if there is a match
-            dehyphenator = Dehyphenator()
-            html = dehyphenator(html,'html_cleanup', length)
-        else:
-            # dehyphenate in cleanup mode to fix anything previous conversions/editing missed
-            self.log("Cleaning up hyphenation")
-            dehyphenator = Dehyphenator()
-            html = dehyphenator(html,'html_cleanup', length)
-            self.log("Done dehyphenating")
+        if getattr(self.extra_opts, 'unwrap_lines', True):
+            # Determine line ending type
+            # Some OCR sourced files have line breaks in the html using a combination of span & p tags
+            # span are used for hard line breaks, p for new paragraphs.  Determine which is used so
+            # that lines can be un-wrapped across page boundaries
+            format = self.analyze_line_endings(html)
 
-        # delete soft hyphens
-        html = re.sub(u'\xad\s*(</span>\s*(</[iubp]>\s*<[iubp][^>]*>\s*)?<span[^>]*>|</[iubp]>\s*<[iubp][^>]*>)?\s*', '', html)
+            # Check Line histogram to determine if the document uses hard line breaks, If 50% or
+            # more of the lines break in the same region of the document then unwrapping is required
+            docanalysis = DocAnalysis(format, html)
+            hardbreaks = docanalysis.line_histogram(.50)
+            self.log("Hard line breaks check returned "+unicode(hardbreaks))
+
+            # Calculate Length
+            unwrap_factor = getattr(self.extra_opts, 'html_unwrap_factor', 0.4)
+            length = docanalysis.line_length(unwrap_factor)
+            self.log("Median line length is " + unicode(length) + ", calculated with " + format + " format")
+
+            # only go through unwrapping code if the histogram shows unwrapping is required or if the user decreased the default unwrap_factor
+            if hardbreaks or unwrap_factor < 0.4:
+                self.log("Unwrapping required, unwrapping Lines")
+                # Dehyphenate with line length limiters
+                dehyphenator = Dehyphenator()
+                html = dehyphenator(html,'html', length)
+                html = self.punctuation_unwrap(length, html, 'html')
+                #check any remaining hyphens, but only unwrap if there is a match
+                dehyphenator = Dehyphenator()
+                html = dehyphenator(html,'html_cleanup', length)
+
+        if getattr(self.extra_opts, 'dehyphenate', True):
+            # dehyphenate in cleanup mode to fix anything previous conversions/editing missed
+            self.log("Fixing hyphenated content")
+            dehyphenator = Dehyphenator()
+            html = dehyphenator(html,'html_cleanup', length)
 
         # If still no sections after unwrapping mark split points on lines with no punctuation
-        if self.html_preprocess_sections < self.min_chapters:
+        if self.html_preprocess_sections < self.min_chapters and getattr(self.extra_opts, 'markup_chapter_headings', False):
             self.log("Looking for more split points based on punctuation,"
                     " currently have " + unicode(self.html_preprocess_sections))
             chapdetect3 = re.compile(r'<(?P<styles>(p|div)[^>]*)>\s*(?P<section>(<span[^>]*>)?\s*(?!([*#•]+\s*)+)(<[ibu][^>]*>){0,2}\s*(<span[^>]*>)?\s*(<[ibu][^>]*>){0,2}\s*(<span[^>]*>)?\s*.?(?=[a-z#\-*\s]+<)([a-z#-*]+\s*){1,5}\s*\s*(</span>)?(</[ibu]>){0,2}\s*(</span>)?\s*(</[ibu]>){0,2}\s*(</span>)?\s*</(p|div)>)', re.IGNORECASE)
             html = chapdetect3.sub(self.chapter_break, html)
+
         # search for places where a first or second level heading is immediately followed by another
         # top level heading.  demote the second heading to h3 to prevent splitting between chapter
         # headings and titles, images, etc
         doubleheading = re.compile(r'(?P<firsthead><h(1|2)[^>]*>.+?</h(1|2)>\s*(<(?!h\d)[^>]*>\s*)*)<h(1|2)(?P<secondhead>[^>]*>.+?)</h(1|2)>', re.IGNORECASE)
         html = doubleheading.sub('\g<firsthead>'+'\n<h3'+'\g<secondhead>'+'</h3>', html)
 
-        # put back non-breaking spaces in empty paragraphs to preserve original formatting
-        html = blankreg.sub('\n'+r'\g<openline>'+u'\u00a0'+r'\g<closeline>', html)
+        if getattr(self.extra_opts, 'format_scene_breaks', True):
+            # Center separator lines
+            html = re.sub(u'<(?P<outer>p|div)[^>]*>\s*(<(?P<inner1>font|span|[ibu])[^>]*>)?\s*(<(?P<inner2>font|span|[ibu])[^>]*>)?\s*(<(?P<inner3>font|span|[ibu])[^>]*>)?\s*(?P<break>([*#•]+\s*)+)\s*(</(?P=inner3)>)?\s*(</(?P=inner2)>)?\s*(</(?P=inner1)>)?\s*</(?P=outer)>', '<p style="text-align:center; margin-top:1.25em; margin-bottom:1.25em">' + '\g<break>' + '</p>', html)
 
-        # Center separator lines
-        html = re.sub(u'<(?P<outer>p|div)[^>]*>\s*(<(?P<inner1>font|span|[ibu])[^>]*>)?\s*(<(?P<inner2>font|span|[ibu])[^>]*>)?\s*(<(?P<inner3>font|span|[ibu])[^>]*>)?\s*(?P<break>([*#•]+\s*)+)\s*(</(?P=inner3)>)?\s*(</(?P=inner2)>)?\s*(</(?P=inner1)>)?\s*</(?P=outer)>', '<p style="text-align:center">' + '\g<break>' + '</p>', html)
+        if self.deleted_nbsps:
+            # put back non-breaking spaces in empty paragraphs to preserve original formatting
+            html = self.blankreg.sub('\n'+r'\g<openline>'+u'\u00a0'+r'\g<closeline>', html)
 
         return html