...

src/calibre/ebooks/pdf/reflow.py

@@ -23,6 +23,7 @@ class Text(object):
         self.font_map = font_map
         self.top, self.left, self.width, self.height = map(float, map(text.get,
             ('top', 'left', 'width', 'height')))
+        self.bottom  = self.top + self.height
         self.font = self.font_map[text.get('font')]
         self.font_size = self.font.size
         self.color = self.font.color
@@ -31,6 +32,18 @@ class Text(object):
         self.text_as_string = etree.tostring(text, method='text',
                 encoding=unicode)
 
+class FontSizeStats(dict):
+
+    def __init__(self, stats):
+        total = float(sum(stats.values()))
+        self.most_common_size, self.chars_at_most_common_size = -1, 0
+
+        for sz, chars in stats.items():
+            if chars >= self.chars_at_most_common_size:
+                self.most_common_size, self.chars_at_most_common_size = sz, chars
+            self[sz] = chars/total
+
+
 class Page(object):
 
     def __init__(self, page, font_map, opts, log):
@@ -46,6 +59,15 @@ class Page(object):
         for text in page.xpath('descendant::text'):
             self.texts.append(Text(text, self.font_map, self.opts, self.log))
 
+        self.font_size_stats = {}
+        for t in self.texts:
+            if t.font_size not in self.font_size_stats:
+                self.font_size_stats[t.font_size] = 0
+            self.font_size_stats[t.font_size] += len(t.text_as_string)
+
+        self.font_size_stats = FontSizeStats(self.font_size_stats)
+
+
 
 class PDFDocument(object):
 
@@ -69,6 +91,17 @@ class PDFDocument(object):
             self.page_map[page.id] = page
             self.pages.append(page)
 
+        self.collect_font_statistics()
+
+    def collect_font_statistics(self):
+        self.font_size_stats = {}
+        for p in self.pages:
+            for sz, chars in p.font_size_stats:
+                if sz not in self.font_size_stats:
+                    self.font_size_stats[sz] = 0
+                self.font_size_stats[sz] += chars
+
+        self.font_size_stats = FontSizeStats(self.font_size_stats)