From 3d6c3de3161d5f53c75ab4623eb5ccfd984c1c57 Mon Sep 17 00:00:00 2001
From: Andrey Golovizin <ag@sologoc.com>
Date: Fri, 8 Aug 2014 15:53:23 +0200
Subject: [PATCH] Add Page, Line and Letter classes.

---
 pixelocr/image.py | 34 +++++++++++++++++++++++++++-------
 1 file changed, 27 insertions(+), 7 deletions(-)

diff --git a/pixelocr/image.py b/pixelocr/image.py
index 6f2e407..4c03c28 100644
--- a/pixelocr/image.py
+++ b/pixelocr/image.py
@@ -7,9 +7,11 @@ from skimage.color import rgb2gray
 from .utils import cached_property
 
 
-class Image(IPythonImageMixin):
+class Image(object):
     """Basic image class."""
 
+    child_cls = None
+
     def __init__(self, data):
         self._data = data
 
@@ -77,7 +79,10 @@ class Image(IPythonImageMixin):
     def unframe(self, width=2):
         return self[width:-width,width:-width]
 
-    def iter_lines(self, min_space=200):
+    def _iter_children(self, min_space):
+        if self.child_cls is None:
+            raise NotImplementedError
+
         line_start = None
         prev_line_end = 0
         for i, row in enumerate(self.bitmap):
@@ -85,13 +90,28 @@ class Image(IPythonImageMixin):
                 if line_start is None:
                     line_start = i
                     if line_start - prev_line_end >= min_space:
-                        yield Image.space(line_start - prev_line_end, self.width)
+                        yield self.child_cls.space(line_start - prev_line_end, self.width)
             else:
                 if line_start is not None:
-                    yield self[line_start:i, :]
+                    yield self.child_cls(self._data[line_start:i, :])
                     line_start = None  
                     prev_line_end = i
 
-    def iter_letters(self, min_space=10):
-        for letter in self.T.iter_lines(min_space=7):
-            yield letter.T
+
+class Page(Image):
+    child_cls = Line
+
+    def __iter__(self):
+        return self._iter_children(min_space=200)
+
+
+class Line(Image):
+    child_cls = Letter
+
+    def __iter__(self):
+        for rotated_letter in self.T._iter_children(min_space=10):
+            yield rotated_letter.T
+
+
+class Letter(Image):
+    pass