Adding language correction file for Germany (deu).

mayan/apps/ocr/lang/deu.py

@@ -0,0 +1,43 @@
+# -*- coding: utf-8 -*-
+import re
+
+
+def check_word(word):
+    ALL_ALPHANUM = re.compile('([0-9a-zäöüß])', re.I)
+    NON_ALPHANUM = re.compile('([^0-9a-zäöüß])', re.I)
+    ALL_ALPHANUM = re.compile('([0-9a-z])', re.I)
+    NON_ALPHANUM = re.compile('([^0-9a-z])', re.I)
+
+    TOO_MANY_VOWELS = re.compile('[aäeioöuü]{4}', re.I)
+    TOO_MANY_CONSONANTS = re.compile('[bcdfghjklmnpqrstvwxyz]{4}', re.I)
+    ALL_ALPHA = re.compile('^[a-z]+$', re.I)
+    # SINGLE_LETTER_WORDS = re.compile('^$', re.I)
+
+    #(L) If a string is longer than 40 characters, it is considered as garbage
+    # http://www.duden.de/sprachwissen/sprachratgeber/die-laengsten-woerter-im-dudenkorpus
+    # http://www.duden.de/sprachwissen/sprachratgeber/durchschnittliche-laenge-eines-deutschen-wortes
+    if len(word) > 40:
+        return None
+
+    #(A) If a string's ratio of alphanumeric characters to total
+    #characters is less than 50%, the string is garbage
+    if len(ALL_ALPHANUM.findall(word)) < len(word) / 2:
+        return None
+
+    #Remove word if all the letters in the word are non alphanumeric
+    if len(NON_ALPHANUM.findall(word)) == len(word):
+        return None
+
+    #Removed words with too many consecutie vowels
+    if TOO_MANY_VOWELS.findall(word):
+        return None
+
+    #Removed words with too many consecutie consonants
+    if TOO_MANY_CONSONANTS.findall(word):
+        return None
+
+    # No single letter words in German
+    if len(word) == 1:
+        return None
+
+    return word