Fixed: crash with negative layout bbox.

pdfminer/layout.py

@@ -472,7 +472,8 @@ class LTLayoutContainer(LTContainer):
         self.groups = None
         return
 
-    def get_textlines(self, laparams, objs):
+    # group_objects: group text object to textlines.
+    def group_objects(self, laparams, objs):
         obj0 = None
         line = None
         for obj1 in objs:
@@ -538,13 +539,14 @@ class LTLayoutContainer(LTContainer):
         yield line
         return
 
-    def get_textboxes(self, laparams, lines):
+    # group_textlines: group neighboring lines to textboxes.
+    def group_textlines(self, laparams, lines):
         plane = Plane(self.bbox)
         plane.extend(lines)
         boxes = {}
         for line in lines:
             neighbors = line.find_neighbors(plane, laparams.line_margin)
-            assert line in neighbors, line
+            if line not in neighbors: continue
             members = []
             for obj1 in neighbors:
                 members.append(obj1)
@@ -559,6 +561,7 @@ class LTLayoutContainer(LTContainer):
                 boxes[obj] = box
         done = set()
         for line in lines:
+            if line not in boxes: continue
             box = boxes[line]
             if box in done:
                 continue
@@ -567,6 +570,7 @@ class LTLayoutContainer(LTContainer):
                 yield box
         return
 
+    # group_textboxes: group textboxes hierarchically.
     def group_textboxes(self, laparams, boxes):
         assert boxes
 
@@ -633,18 +637,16 @@ class LTLayoutContainer(LTContainer):
     def analyze(self, laparams):
         # textobjs is a list of LTChar objects, i.e.
         # it has all the individual characters in the page.
-        (textobjs, otherobjs) = fsplit(lambda obj: isinstance(obj, LTChar), self._objs)
+        (textobjs, otherobjs) = fsplit(lambda obj: isinstance(obj, LTChar), self)
         for obj in otherobjs:
             obj.analyze(laparams)
         if not textobjs:
             return
-        textlines = list(self.get_textlines(laparams, textobjs))
-        assert len(textobjs) <= sum(len(line._objs) for line in textlines)
+        textlines = list(self.group_objects(laparams, textobjs))
         (empties, textlines) = fsplit(lambda obj: obj.is_empty(), textlines)
         for obj in empties:
             obj.analyze(laparams)
-        textboxes = list(self.get_textboxes(laparams, textlines))
-        assert len(textlines) == sum(len(box._objs) for box in textboxes)
+        textboxes = list(self.group_textlines(laparams, textlines))
         if textboxes:
             self.groups = self.group_textboxes(laparams, textboxes)
             assigner = IndexAssigner()

pdfminer/utils.py

@@ -259,6 +259,8 @@ class Plane(object):
         return obj in self._objs
 
     def _getrange(self, (x0, y0, x1, y1)):
+        if (x1 <= self.x0 or self.x1 <= x0 or
+            y1 <= self.y0 or self.y1 <= y0): return
         x0 = max(self.x0, x0)
         y0 = max(self.y0, y0)
         x1 = min(self.x1, x1)

samples/nonfree/naacl06-shinyama.xml.ref

@@ -3750,14 +3750,14 @@
 </textgroup>
 </textgroup>
 <textgroup bbox="313.198,119.636,540.091,607.829">
-<textgroup bbox="313.198,336.837,540.091,607.829">
 <textbox id="11" bbox="313.198,513.386,540.091,607.829" />
+<textgroup bbox="313.198,119.636,540.091,512.573">
 <textbox id="12" bbox="313.198,336.837,540.091,512.573" />
-</textgroup>
 <textbox id="13" bbox="313.198,119.636,540.091,336.023" />
 </textgroup>
 </textgroup>
 </textgroup>
+</textgroup>
 </layout>
 </page>
 </pages>